Diabetes

Coding Dimension ID: 
289
Coding Dimension path name: 
Diabetes

Deciphering transcriptional control of pancreatic beta-cell maturation in vitro

Funding Type: 
Basic Biology IV
Grant Number: 
RB4-06144
ICOC Funds Committed: 
$1 391 400
Disease Focus: 
Diabetes
Stem Cell Use: 
Embryonic Stem Cell
oldStatus: 
Active
Public Abstract: 
The loss of pancreatic beta-cells in type 1 diabetes results in absence of insulin secreted by the pancreas, and consequently elevated blood sugar which leads to various long-term complications. Diabetic patients would benefit tremendously from availability of transplantable replacement beta-cells. Much of current research focuses on producing beta-cells from stem cells. Despite some progress, it is at present still not possible to generate functional beta-cells in culture. The beta-like cells generated with current protocols in vitro lack key features of normal beta-cells, most notably the ability to secrete insulin a regulated manner. However, when stem cell-derived beta-cell precursors are transplanted into mice, they acquire properties of functional beta-cells, indicating that the precursors have the potential to transition into a mature beta-cell state. By comprehensively comparing the molecular profiles of mature, functional beta-cells and malfunctioning insulin-producing cells generated in vitro, we have identified molecular cues that are not appropriately induced under current culture conditions. These studies have led to short list of candidate regulators of beta-cell maturation. We propose to manipulate these candidate factors in stem cell-derived beta-cell precursors in culture, with the goal of forcing them to adopt a mature phenotype. We will first characterize these cells in vitro and then test functionality in diabetic animal models.
Statement of Benefit to California: 
Diabetes is a metabolic disorder that affects 8.3% of the U.S. population. Average medical expenditures among people with diabetes are 2.3 times higher than those of people without diabetes. The disease is characterized by either absolute insulin deficiency due to the autoimmune destruction of pancreatic insulin-producing beta-cells [Type 1 diabetes], or relative insulin deficiency due to defective insulin secretion or insulin sensitivity [Type 2 diabetes]. The resulting elevated blood glucose levels eventually lead to damage of the blood vessels followed by kidney failure, blindness, neuropathy, heart disease, and stroke. Despite current treatment regimens of several insulin injections per day, blood glucose levels still fluctuate significantly in diabetic patients, making diabetes the seventh leading cause of death in the United States. Alternative approaches to insulin injections include attempts to develop a cell therapy by producing transplantable beta-cells from stem cells. A cell therapy would lead to better blood glucose control and therefore ameliorate long-term complications. This proposal seeks to identify factors that force stem cell-derived beta-cells to functionally mature in culture with the goal to produce an unlimited source of transplantable beta-cells. Given the high prevalence of diabetes in California, we believe that the proposed research will have tremendous benefit to the State of California and its citizens.
Progress Report: 
  • The loss of pancreatic beta-cells in type 1 diabetes results in absence of insulin secreted by the pancreas, and consequently elevated blood sugar which leads to various long-term complications. Diabetic patients would benefit tremendously from availability of transplantable replacement beta-cells. Much of current research focuses on producing beta-cells from stem cells. Despite some progress, it is at present still not possible to generate functional beta-cells in culture. The beta-like cells generated with current protocols in vitro lack key features of normal beta-cells, most notably the ability to secrete insulin a regulated manner. However, when stem cell-derived beta-cell precursors are transplanted into mice, they acquire properties of functional beta-cells, indicating that the precursors have the potential to transition into a mature beta-cell state.
  • This proposal explores strategies for maturing beta-cell precursors in the culture dish with the goal to produce fully functional insulin-producing beta-cells in vitro. Previous studies from our laboratory have resulted in a short list of candidate regulators of beta-cell maturation. We propose to manipulate these candidate regulators in vitro in order to force beta-cell precursors to adopt a mature phenotype. We have now established a robust in vitro system for culturing and manipulating beta-cell precursors. We have also generated and tested requisite reagents for manipulating precursors in the culture dish. Over the next year, we will obtain first results from these manipulations.

Biological relevance of microRNAs in hESC differentiation to endocrine pancreas

Funding Type: 
Basic Biology III
Grant Number: 
RB3-02266
ICOC Funds Committed: 
$1 313 649
Disease Focus: 
Diabetes
Stem Cell Use: 
Embryonic Stem Cell
oldStatus: 
Active
Public Abstract: 
There remains an urgent and critical need for a cell-based cure of diabetes, one of the most costly diseases in California. Islet transplantation with persistent immune suppression has shown promise in curing type 1 diabetes (TID). However, one major obstacle towards large scale implementation of this approach is the shortage of engraftable islets. Human ES cells (hESCs), which can undergo unlimited self-renewal and differentiate into all cell types in the body, have the potential to become an unlimited source of pancreatic β cells. Significant challenges, including the lack of chemical defined conditions for reproducibly differentiating hESCs into endocrine precursors (EPs), lack of strategy to purify these EPs to avoid teratoma risk, and destruction of engrafted islets by allogeneic and autoimmune rejection despite persistent immune suppression, hinder clinic development of this promising hESC based therapy. Ongoing research in our laboratories is directed at developing novel strategies to derive β-cells from hESCs. Of the several genetic factors that contribute to stem cells differentiation, miRs (microRNAs) are emerging as important determinants. We hypothesize that identification and validation of the temporal expression of miRs at discrete, functionally defined and genetically marked stages of hESC differentiation to insulin-producing cells, when combined with a computational/systems biology approach, will create a population of cells of significant therapeutic impact. The proposed studies will translate basic large-scale analysis of miR and mRNA from pancreatic precursors derived from hESC into a fundamental understanding of differentiation. This in turn will ultimately lead to novel treatments for T1D. In this project we will elucidate the importance of miRs in pancreatic cell differentiation through functional testing, genetic marking, deep sequencing, computational analysis, and validation. Within the context of the above-stated general aims the sequencing studies will be initiated for 3 reasons: 1) to establish on site the most powerful approaches currently available for measuring gene identity and expression 2) to ensure that novel and established miRs are evaluated for changes in expression during hESC differentiation 3) to validate targets of miR action. Application of this emerging technology to β-cell genesis will allow the generation of miR and mRNA profiles from uniform cell populations and validation through functional assays. Together, this information will help to better understand, describe, and ultimately optimize hESC differentiation. Basic research from this project has the potential to create a paradigm shift in understanding the cellular ontogeny of the pancreas and help identify which cell types can be used for transplantation therapy in T1D.
Statement of Benefit to California: 
Diabetes has devastating consequences on both those afflicted and on State/National healthcare costs, and, given the staggering rise in both occurrence and costs, diabetes alone possesses the potential to completely overwhelm our healthcare system. There remains an urgent and critical need for a cell-based cure. In 2007, diabetes directly affected 1 in 10 Californians (2.7 million), costing the state $24.5B annually. There have been documented, significant increases in the occurrence of both type 1 and type 2 diabetes in youths under 18 years of age (0.16% of youth <18 yr have type 1 diabetes nationally). There are more than 7,000 diabetic children within [REDACTED] alone. The following alarming statistics are provided by the California Department of Public Health, California Diabetes Control Program, CDC and NIH/NIDDK: • In the U.S., diabetes is the most costly chronic disease, costing $132B annually. This is predicted to rise to $192B by 2020. • Nearly 1 in 3 Medicare dollars and 1 in 10 of U.S. healthcare dollars are spent treating diabetes. • Diabetics average $13,243/year in health care costs, 2.4 times more than non-diabetics. • 7% of the US population has diabetes. • Every 24 hours, 4,100 Americans are diagnosed with diabetes, 613 American diabetics die of the disease and another 55 go blind. • Worldwide, every 10 seconds a diabetic dies and two new people develop diabetes. • Worldwide expenditures on insulin alone are estimated to be $15 billion annually and growing. This research would benefit the State of California and its citizens on multiple fronts. First and foremost, positive results will create a new development candidate for cell-based therapy for type 1 diabetes with the potential for avoiding the risk of tumor formation - a consequence that hinders the development of any human ES cell based therapy. Second, the application of new technologies would enhance the prospects for new biological agents that will require scale up efforts not available to academics. The creation of progenitor cells for any chronic disease, diabetes in our case, will enhance the prospects for the increase in personnel at the scientific and technical level for both academic labs and biotech companies. Finally, this work may obviate the need for immune suppression therapy that today carries serious side effects including propensity to infections and cancer, abnormalities in lipid metabolism and hypertension, and even damage to the transplanted cells as it occurs following islet transplantation procedures, the only available therapy nowadays for insulin-dependent diabetes. Avoidance of these complications represents a significant positive step in the reduction of health care expenses directly attributed to diabetes and its complications.
Progress Report: 
  • The long term goal of our research is to understand the biochemical processes that regulate differentiation of human embryonic stem cells (hESCs) into pancreatic progenitor cells, and ultimately, glucose-responsive, insulin producing (beta) β cells. Islet transplantation with persistent immune suppression has shown promise in curing type 1 diabetes (TID). However, one major obstacle towards large scale implementation of this approach is the shortage of engraftable islets. hESCs, which can undergo unlimited self-renewal and differentiate into all cell types in the body, have the potential to become an unlimited source of pancreatic β cells, however, significant challenges have hindered clinic development of this promising hESC based therapy.
  • Ongoing research in our laboratory is directed at deriving β-cells from hESCs. Of the several genetic factors that contribute to stem cells differentiation, miRNAs (microRNAs) are emerging as important determinants. miRNAs are noncoding, regulatory RNAs expressed dynamically during differentiation of hESC. Mapping developmental expression of miRNAs during transition from pluripotency to pancreatic progenitors will help clarify the mechanisms underlying lineage specification and ultimately enhance differentiation protocols. Specifically, the objectives of this CIRM grant are to elucidate the role miRNAs play in the development of hESC into cells of endocrine lineage and to provide crucial details on the molecular architecture of endocrine precursor populations, lineage specification, and β-cell maturation.
  • The central hypothesis driving the research is that miRNAs are essential regulators of endocrine cell development. We are working under the postulate that miRNAs are logical targets for in vitro experimentation because of their role in mediating pancreatic cell development. Our aims are as follow:
  • Aim 1 - Generate miR expression profiles using deep sequencing for defined stages of development from pluripotent to endocrine cells and select candidate miRs for manipulations involving silencing and overexpression.
  • Aim 2 - Identify miRs targets through deep sequencing of RNA induced silencing complexes (RISC) in defined cell populations and assessment of their roles in differentiation in vitro and after experimental transplantation.
  • During the current funding period, progress has been made on both specific aims originally proposed. From this work, one manuscript and one review article have been published and two other research articles are submitted/in review.
  • Published studies. A) “The SDF-1α/CXCR4 axis is required for proliferation and maturation of human fetal pancreatic endocrine progenitor cells.” was published in PLoSONE. B) “From pluripotency to islets: miRNAs as critical regulators of human cellular differentiation” was published in Advances in Genetics.
  • Submitted studies. A) “sRNA-seq analysis of human embryonic stem cells and definitive endoderm reveal differentially expressed microRNAs and novel isomiRs with distinct targets” is in revision at Stem Cells. B) “Jak/Stat and MAP kinase signaling regulate human embryonic stem cell pluripotency” will be re-submitted to Cell Stem Cell in early October.
  • Work in progress. A) Deep sequencing of miRNAs from a purified population of PDX-1+ cells derived from hESC. Towards our goal of understanding the role miRNAs play in driving differentiation of insulin producing cells from pluripotent hESC, we have sequenced miRNAs from a heterogeneous population of hESC that have been directed towards endocrine lineage. B) Deep sequencing of miRNAs at 24 hour intervals during hESC differentiation towards pancreatic precursors. A major undertaking during the first year of funding is to sequence the changes in miRNA expression at selected intervals during the differentiation process. This information is critical for us to develop algorithms to determine how miRNAs drive differentiation and for identification of miRNA/mRNA targets. C) Development of algorithms to analyze change in miR expression in complex systems. During the first phases of the CIRM project, Natural Selection Inc. focused on algorithms to analyze change in microRNA expression over multiple data sets. D) Generation of a population of PDX1+ cells using zinc finger nuclease technology. One critical goal of the proposed studies is to generate a purified population of endocrine precursor cells. Although some technical problems with construction of the vector arose, we believe that we have overcome the major obstacles and will have these cells for microRNA analysis during the next funding period.
  • Together, the information generated in this study is helping us to better understand, describe, and ultimately optimize hESC differentiation. We believe that the results from this project have the potential to create a paradigm shift in understanding the cellular ontogeny of the pancreas and help identify which cell types can be used for transplantation therapy in T1D.
  • The long term goal of our research is to understand the biochemical processes that regulate differentiation of human embryonic stem cells (hESCs) into pancreatic progenitor cells, and ultimately, glucose-responsive, insulin producing (beta) β cells. hESCs, which can undergo unlimited self-renewal and differentiate into all cell types in the body, have the potential to become an unlimited source of pancreatic β cells, however, significant challenges have hindered clinic development of this promising hESC based therapy.
  • Ongoing research in our laboratory is directed at deriving β-cells from hESCs. Of the several genetic factors that contribute to stem cells differentiation, miRNAs (microRNAs) are emerging as important determinants. miRNAs are noncoding, regulatory RNAs expressed dynamically during differentiation of hESC. Mapping developmental expression of miRNAs during transition from pluripotency to pancreatic progenitors will help clarify the mechanisms underlying lineage specification and ultimately enhance differentiation protocols. Specifically, the objectives of this CIRM grant are to elucidate the role miRNAs play in the development of hESC into cells of endocrine lineage and to provide crucial details on the molecular architecture of endocrine precursor populations, lineage specification, and β-cell maturation.
  • The central hypothesis driving the research is that miRNAs are essential regulators of endocrine cell development. We are working under the postulate that miRNAs are logical targets for in vitro experimentation because of their role in mediating pancreatic cell development. Our aims are as follow:
  • Aim 1 - Generate miR expression profiles using deep sequencing for defined stages of development from pluripotent to endocrine cells and select candidate miRs for manipulations involving silencing and overexpression.
  • Aim 2 - Identify miRs targets through deep sequencing of RNA induced silencing complexes (RISC) in defined cell populations and assessment of their roles in differentiation in vitro and after experimental transplantation.
  • During the current funding period, progress has been made on both specific aims originally proposed.
  • Published studies. “A) “Imaging human fetal pancreas.” was published in Journal of Visualized Experiments.
  • Provisional Patents Filed. A) “Novel combinations of transcriptional gene regulators”. B) “Assay to detect onco-miRs circulating in serum or cells”
  • Work in progress.
  • A) Paired microRNA expression and development of a reporter system for lineage fate.
  • We have made a cell line that reports the expression of PDX1, a marker for both pancreatic precursors and for mature beta cells, in order to select and purify the target cells in late differentiation. miR-375 was previously described by our lab to be the most abundant miRNA in definitive endoderm (DE). Other labs have shown that miR-375 is also expressed in pancreatic during development, and specifically in beta cells in mature islets, where it regulates insulin secretion. Conversely, miR-122 is the most highly expressed miRNA in liver, which arises in the region of endoderm that is closest to the pancreatic buds. In our hESC differentiation protocol, only miR-375 is expressed at the DE stage, which is typically about 98% pure. miR-122 is not expressed in DE, but increases in levels to coincide with lower miR-375 expression as a more heterogeneous mixture of cells form as DE differentiates into multiple lineages. We have generated a reporter cell lines that can distinguish pancreatic cells from liver cells in post-DE differentiation, and possibly mature beta cells from other endocrine cells.
  • B) Deep sequence purified hESC populations from selected time points during hESC differentiation and develop algorithms to analyze change in miRNA expression in complex systems.
  • In our previous approach, we applied pattern filters to the data to see which miRs matched a particular filter. This was valuable as it helped us determine which miRs had similar expression patterns. However there was still a lot of variance. Therefore, we wre-did the analysis using a new clustering methods developed in conjunction with NSI. The latest approach has given us very valuable insight into the data. We have found that master regulators of miRs exist and/or are being regulated by another regulator but that regulator is biasing them over a large time scale (weeks). The day-to-day fluctuations that most investigators focus upon are not found in this latest group, suggesting that short-term and long-term miR regulation are differentially regulated.
  • Together, the information generated in this study is helping us to better understand, describe, and ultimately optimize hESC differentiation. We believe that the results from this project have the potential to create a paradigm shift in understanding the cellular ontogeny of the pancreas and help identify which cell types can be used for transplantation therapy in T1D.

Developing induced pluripotent stem cells into human therapeutics and disease models

Funding Type: 
Early Translational I
Grant Number: 
TR1-01277
ICOC Funds Committed: 
$5 165 028
Disease Focus: 
Diabetes
Stem Cell Use: 
iPS Cell
Cell Line Generation: 
iPS Cell
oldStatus: 
Closed
Public Abstract: 
Human embryonic stem cells (hESCs) can undergo unlimited self-renewal and differentiate into all the cell types in the human body, and thus hold great promise for cell replacement therapy. However, one major problem for hESC-based therapy is that the cells derived from hESCs will be rejected by the recipient and can only be tolerated under persistent immunosuppression, which itself can cause cancer and infection. Recent development of induced pluripotent stem cells (iPSCs), which are generated from somatic cells of individual patient with defined factors and very similar to hESCs, could provide ideal cell source for transplantation by avoiding graft rejection in the patient. In addition, the disease-specific iPSCs can be used as human disease models for more reliable testing of the efficacy and toxicity of drugs. However, there are several major bottlenecks that prevent the development of iPSCs in human therapy and drug discovery. The overall goal of this proposal is to resolve the major bottlenecks remained in human iPSC biology to make it feasible for human therapy and drug discovery. We propose to develop safe and efficient approach to generate iPSCs from human patients. We propose to develop strategies to eliminate the risk of teratomas associated with the undifferentiated iPSCs. We propose to develop mouse model with functional human immune system to study the immune responses and tolerance during transplantation. Resolving these bottlenecks will greatly facilitate the development of hESCs into stem cell therapy and disease models for drug discovery.
Statement of Benefit to California: 
Diabetes and heart diseases remain the most costly diseases in our State and Nation. In the case of diabetes, 1 of every 10 Californians (2.7 million) were afflicted with diabetes in 2007, costing the State $24.5 billion annually. There is a significant increase in the occurrence of both types of diabetes in youths under 18 years of age (0.16% of youth <18 yr have type 1 diabetes nationally). Simply put, diabetes is having devastating consequences on both those afflicted and on State/National healthcare costs, and, given the staggering rise in both occurrence and costs, diabetes possesses the potential to completely overwhelm our healthcare system. There remains an urgent and critical need for a cell-based cure of diabetes. There is hope, since transplantation of functional β cells from human donors has been validated clinically to cure diabetes. While significant progress has been made in the derivation of functional β cells and cardiomyocytes from human ES cells, these allogenic cells will be rejected by the recipient upon transplantation unless the immune system of the recipient is persistently suppressed. However, immune suppression itself has severe consequences with significantly increased risk of cancer and infection. This problem might be resolved by the recent breakthrough in induced pluripotent stem cell (iPSCs), which can be reprogrammed from somatic cells of human patients by defined factors and thus can provide a renewable source of autologous cells for transplantation. In addition, the disease-specific iPSCs will provide the much needed disease models to more reliably predict the drug responses in humans. With our significant progress in producing iPSCs without viral vectors or permanent genetic modification, our proposed research will resolve the major bottlenecks that hinder the development of iPSCs into human therapy and drug discovery. If successful, the funding spent now on research is nominal when compared to the billions that will be saved in treatment costs and the improved quality of life for patients.
Progress Report: 
  • Human induced pluripotent stem cells (hiPSCs), reprogrammed from somatic cells with defined factors, are similar to human ES cells (hESCs) and could provide ideal cell source for transplantation by avoiding immune rejection. In addition, disease-specific hiPSCs could provide improved disease models to predict drug responses in humans. The permanent genetic modification by random viral integration and spontaneous reactivation of reprogramming factors lead to cancer risk and abnormal differentiation. During the past year, we have made progresses to develop a combination of chemical and episomal approaches to reprogram human cells into iPSCs without genetic modifications. We have developed the constructs for the pre-transplant strategies to eliminate the teratomas risk of undifferentiated iPSCs. We have started to improve conditions for iPSC differentation into beta cells. In addition, we developed mouse models reconstituted with human immune system to enable us to study the immunogenicity and tolerance of cells derived from isogenic iPSCs.
  • During the past year, we have made significant progress in the proposed research. One most important finding is the discovery of the immunogenicity of the cells derived from induced pluripotent stem cells (iPSCs). This immunogenicity is due to the abnormal gene expression during the differentiation of iPSCs. This finding, published in the journal Nature, indicates that we need to perform more research on iPSCs before moving forward into clinical trial. Another major finding is the discovery of a safer way to improve the efficiency of iPSC production. In addition, we have made some progress in developing a genetic approach to eliminate the teratomas risk associated with the undifferentiated pluripotent stem cells.
  • During the past funding period, we have accomplished the established milestones. We have compared the genomic stability of iPSCs generated with various approaches. We have developed a genetic approach to eliminate the teratomas risk associated with undifferentiated pluripotent stem cells. We have evaluated the immunogenicity of cells derived from human iPSCs.
  • We have achieved the milestones and completed the proposed research during the no-cost extension period.

Methods for detection and elimination of residual human embryonic stem cells in a differentiated cell product

Funding Type: 
Early Translational I
Grant Number: 
TR1-01215
ICOC Funds Committed: 
$5 405 397
Disease Focus: 
Diabetes
Collaborative Funder: 
Victoria, Australia
Stem Cell Use: 
Embryonic Stem Cell
oldStatus: 
Active
Public Abstract: 
Human embryonic stem cells (hESC), and other related pluripotent stem cells, have great potential as starting material for the manufacture of curative cell therapies. This is primarily for two reasons. First, by manipulating cues in their cell culture conditions, these cells can be directed to become essentially any desired human cell type (a property known as pluripotency). Second, hESC have the remarkable capacity to expand rapidly with essentially no change in their identity. At a practical level, this means enough cells to manufacture thousands, and even millions, of therapeutic cell doses can be generated in a matter of weeks. Thus, the biomedical potential is tremendous, but several practical matters remain to be resolved. One of the biggest concerns is that manufacturing processes, i.e., methods to direct “undifferentiated” hESC to become “differentiated” target cell types, have not shown 100% efficiency. That is, some portion of the starting hESC might not differentiate in accordance with the cues given, resulting in a cell therapy product with some contaminating undifferentiated hESC. When undifferentiated hESC are transplanted into animals, they proliferate and differentiate in an uncontrolled, semi-random manner, becoming non-target cell types collectively called a teratoma. Teratomas also occur spontaneously in humans, and consist of a variety of cell types in a disorganized tissue amalgam. Both experimental and spontaneous teratomas are generally benign tumors, and typically can be surgically removed when they become physically problematic due to size or location. While hESC-derived cell therapies have been shown to be effective in animal models of disease, in some instances teratomas have been observed. Thus, the full promise of hESC as source material for novel cell therapies cannot be fully realized until the “teratoma problem” is solved. To date there is no standard method in the field for testing the teratoma potential of a given cell population, nor is there a method for eliminating the potential for teratoma. The proposed project will investigate and establish standardized tests to measure teratoma potential. The tests will be highly sensitive, allowing assurance that large human doses are produced with no risk of teratoma. The project will also investigate a relatively simple method to eliminate undifferentiated hESC in the course of manufacturing. As the last step, the new method will be incorporated into the manufacturing process, the sensitive teratoma tests will be used, and safety data required by the FDA will be collected for a promising new hESC-derived cell therapy for insulin-dependent diabetes. Successful completion of this project will represent a major advance in development of stem cell-derived therapies broadly, and will specifically contribute to the development of a cell therapy for diabetes.
Statement of Benefit to California: 
In large part through CIRM initiatives, California hopes to further establish itself as the world center for stem cell research and stem cell-derived therapies. One major issue standing in the way of stem cell-derived therapy development is the possibility of a teratoma forming after transplant with a stem cell-derived cell therapy. A teratoma is a disorganized tissue amalgam containing various different cell types, and is generally a benign tumor. Teratomas can form in animals transplanted with stem cells, and therefore if some stem cells persist in the stem-cell derived therapy, there exists a possibility that teratomas will form in a patient’s graft. Indeed, putative stem cells have been found in pre-clinical research-grade stem cell-derived cell therapy preparations, and teratomas have been observed in animals treated with those cells. Currently the conditions favorable to teratoma formation are poorly characterized, and methods to reduce the likelihood of teratoma formation have not been developed. The proposed project will establish standardized sensitive methods to measure the teratoma potential of a cell population, will develop a method to reduce or eliminate teratoma potential, and will include both the method to reduce teratoma and the standard measurement of teratoma potential in the development of an actual prospective cell therapy product for the treatment of insulin-dependent diabetes. If successful, this project will remove a significant bottleneck currently holding the development of stem cell-derived cell therapies back, as well as provide essential pre-clinical data for an important stem cell-derived therapy for diabetes, facilitating its clinical testing in diabetics. The State of California will benefit by playing a key role in removing the teratoma bottleneck from the field, as well as in advancing a promising new cell therapy for diabetes, a disease which directly or indirectly affects millions of Californians. Such a therapy could reduce the state's health care costs tremendously.
Progress Report: 
  • ViaCyte is developing a cell therapy for diabetes, which will have a tremendous clinical and societal impact as such a large number of people are afflicted with this disease. The therapy is a combination product comprised of pancreatic progenitor cells transplanted within a device, Encaptra™. A large supply of pancreatic progenitors can be produced with a cell manufacturing process that involves the directed differentiation of human embryonic stem cells (hESC). After transplantation the pancreatic progenitor cells differentiate into functional islets that contain insulin-producing beta cells. Encaptra™ is designed to allow the release of insulin to regulate blood glucose levels while simultaneously protecting the transplanted cells from destruction by the patients’ immune system. The combined product provides a large assurance of safety since cells will be contained and the device is retrievable.
  • This award is focused on product safety, principally the issue of tumorigenicity. Tumor formation is a particular consideration when using hESCs as cell manufacturing starting material since undifferentiated hESCs form a particular type of tumor, called a teratoma, when transplanted into animal models. Therefore, it is important to demonstrate that at the end of the manufacturing process the cell product is largely devoid of undifferentiated hESC and lacks teratoma potential. ViaCyte has been investigating and establishing standardized assays to measure the presence of hESCs and the potential for teratoma formation. In addition, ViaCyte has previously identified several compounds that appear to preferentially kill undifferentiated hESCs while not affecting the viability of pancreatic progenitors. To ensure that Encaptra™ will be fully effective in containing implanted cells in a patient, ViaCyte is developing various assays to ensure the quality of manufactured devices. These newly developed assays will be incorporated into the manufacturing process and data required by the FDA for product safety will be collected. Successful completion of this project will represent a major advance for stem cell-derived therapies and will specifically contribute to establishing a cell therapy for diabetes.
  • ViaCyte is a preclinical company developing a stem cell-based therapy for insulin-dependent diabetes. The therapy is a combination product comprised of pancreatic progenitor cells, pro-islet, encapsulated within a retrievable delivery ENCAPTRA device. After implantation, encapsulated pro-islet differentiates into glucose-responsive, insulin-secreting cells that can regulate normal blood sugar levels in animal models of diabetes. The renewable starting material for pro-islet manufacturing is human embryonic stem cells (hESC) that are directed to differentiate to pancreatic cell product using scalable processes. The bio-stable ENCAPTRA device is designed to fully contain cells and to protect cells from immune attack. The goal is to develop a product that will achieve insulin independence, reduce diabetes-related complications, and eliminate the need for continuous immunosuppressant drugs.
  • This CIRM award is focused on product safety. A large assurance of safety is provided by confining the transplanted cells within the device and by the ability to retrieve the product. Nonetheless, an important preclinical safety assessment of this combination product therapy is the evaluation of its tumorigenicity, i.e. its capacity to form tumors. Upon transplantation into animal models, undifferentiated hESC can generate a teratoma, a tumor that is akin to a particular type of germ cell tumor that can form in humans. There is a possibility that residual, undifferentiated hESC could remain in pro-islet, potentially giving rise to a teratoma. It is unclear whether teratomas can form when undifferentiated hESC are transplanted within ENCAPTRA and if so, what threshold dose of hESC in pro-islet could generate a teratoma.
  • ViaCyte has been investigating and establishing standardized assays to measure the presence of hESC in pro-islet and the potential for teratoma formation. Preliminary tumorigenicity studies of pro-islet were completed with safe outcomes. With these data in hand, formal definitive tumorigenicity studies can be designed and initiated to include in a package to submit to the FDA as ViaCyte seeks approval to test the product in humans. To demonstrate that ENCAPTRA will be effective in containing implanted cells in a patient, ViaCyte is also developing assays to ensure the quality of manufactured devices. These newly developed assays are being incorporated into the cell manufacturing and device manufacturing processes, and data will be collected to show that the product is safe. Successful completion of the objectives of this award will help establish the safety of the product so that clinical trials can be initiated with the goal of developing a game-changing cell therapy for diabetes.
  • ViaCyte is a company developing a stem cell-based therapy for diabetes. The therapy is a combination product, called VC-01™, comprised of human embryonic stem cell (hESC)-derived pancreatic beta cell precursors (PEC-01™ cell product), encapsulated within the Encaptra® drug delivery system (ENCAPTRA device). After implantation, the precursor cells mature into endocrine cells that secrete insulin and other hormones in a regulated manner to control blood sugar levels in animal models of diabetes. hESC are the renewable starting material for cell manufacturing; they are directed to differentiate to PEC-01 cell product using scalable processes. The retrievable ENCAPTRA device is designed to contain cells and to protect cells from immune attack. The goal is to develop a product that will provide insulin independence, reduce diabetes-related complications, and eliminate the need for chronic immunosuppressant drugs.
  • This CIRM award is focused on product safety. An important nonclinical safety assessment of this combination product therapy is the evaluation of its tumorigenicity, i.e., its capacity to form tumors. Upon transplantation into animal models, undifferentiated hESC can generate a teratoma, a tumor that is akin to a particular type of germ cell tumor that can form in humans. Accordingly, to the extent that undifferentiated hESC could potentially remain in the differentiated PEC-01 cell product, these could potentially give rise to a teratoma. Prior to this award, it was unclear whether teratomas will form when undifferentiated hESC are implanted within the ENCAPTRA device and if so, what threshold dose of hESC in PEC-01 would be required to produce a teratoma.
  • ViaCyte received this award to develop methods to assess teratoma potential with in vivo and in vitro assays, and to mitigate potential tumorigenicity risk by ensuring integrity of the encapsulation delivery device. ViaCyte has investigated a standardized assay to measure the presence of hESC in PEC-01 cell product, and preliminary tumorigenicity studies of VC-01 were completed with safe outcomes. With these data in hand, definitive IND-enabling tumorigenicity studies were designed and initiated to include in a package that will be submitted to the FDA as ViaCyte seeks approval to test the product in human clinical trials. A large assurance of safety is provided by confining the transplanted cells within the device and by the ability to retrieve the product. To demonstrate that the ENCAPTRA device will be effective in containing implanted cells in a patient, ViaCyte has also developed assays and performed studies to ensure the integrity of the ENCAPTRA device. Collectively, the data from these studies will form a compelling package to demonstrate the safety of the VC-01 product so that clinical trials can be initiated with the goal of developing a game-changing cell therapy for diabetes.
  • ViaCyte is a company developing a stem cell-based therapy for diabetes. The therapy is a combination product, called VC-01™, comprised of human embryonic stem cell (hESC)-derived pancreatic beta cell precursors (PEC-01™ cell product), encapsulated within the Encaptra® drug delivery system (ENCAPTRA device). After implantation, the precursor cells mature into endocrine cells that secrete insulin and other hormones in a regulated manner to control blood sugar levels in animal models of diabetes. hESC are the renewable starting material for cell manufacturing; they are directed to differentiate to PEC-01 cell product using scalable processes. The retrievable ENCAPTRA device is designed to contain cells and to protect cells from immune attack. The goal is to develop a product that will provide insulin independence, reduce diabetes-related complications, and eliminate the need for chronic immunosuppressant drugs.
  • This CIRM award is focused on product safety. An important nonclinical safety assessment of this combination product therapy is the evaluation of its tumorigenicity, i.e., its capacity to form tumors. Upon transplantation into animal models, undifferentiated hESC can generate a teratoma, a tumor that is akin to a particular type of germ cell tumor that can form in humans. Accordingly, to the extent that undifferentiated hESC could potentially remain in the differentiated PEC-01 cell product, these could potentially give rise to a teratoma. Prior to this award, it was unclear whether teratomas will form when undifferentiated hESC are implanted within the ENCAPTRA device and if so, what threshold dose of hESC in PEC-01 would be required to produce a teratoma.
  • ViaCyte received this award to develop methods to assess teratoma potential with in vivo and in vitro assays, and to mitigate potential tumorigenicity risk by ensuring integrity of the encapsulation delivery device. ViaCyte has investigated a standardized assay to measure the presence of hESC in PEC-01 cell product, and preliminary tumorigenicity studies of VC-01 were completed with safe outcomes. With these data in hand, definitive IND-enabling tumorigenicity studies were designed and initiated to include in a package that will be submitted to the FDA as ViaCyte seeks approval to test the product in human clinical trials. A large assurance of safety is provided by confining the transplanted cells within the device and by the ability to retrieve the product. To demonstrate that the ENCAPTRA device will be effective in containing implanted cells in a patient, ViaCyte has also developed assays and performed studies to ensure the integrity of the ENCAPTRA device. Collectively, the data from these studies will form a compelling package to demonstrate the safety of the VC-01 product so that clinical trials can be initiated with the goal of developing a game-changing cell therapy for diabetes.

Stem cell tolerance through the use of engineered antigen-specific regulatory T cells

Funding Type: 
Transplantation Immunology
Grant Number: 
RM1-01703
ICOC Funds Committed: 
$1 152 768
Disease Focus: 
Diabetes
Immune Disease
Stem Cell Use: 
Embryonic Stem Cell
Cell Line Generation: 
Embryonic Stem Cell
oldStatus: 
Active
Public Abstract: 
Type 1 Diabetes (T1D) occurs as a consequence of uncontrolled immune activation, culminating in the destruction of insulin-producing beta-cells. Efforts to prevent or reverse diabetes have been limited by the lack of safe and effective immunotherapies coupled with the inability to restore insulin producing beta-cells. We believe proper immune control to self-tissues to be a fundamental requirement for any effective therapy, whether the goal is prevention of early beta-cell loss, beta-cell regeneration at disease onset, or ultimately beta-cell replacement in cases of established T1D. To impact disease, any effective therapy must first restore a glucose-responsive insulin-producing beta-cell population. Stem cells represent one of the most promising alternative sources of insulin-producing cells. Second, a therapy must combat the persistent autoimmune attack, as well as any attack directed at foreign tissues following transplantation. The goal of this project is to bring together research efforts in these two complementary areas to fill these critical gaps. Previous studies have focused on the use of regulatory T cells (Tregs) as one key means of restoring immune tolerance in T1D. A key parameter has been the importance of antigen specificity in directing the tissue-protective functions of Tregs. In the prevention setting, antigen-specific Tregs were at least 100-fold more effective in controlling diabetes when compared to Tregs with diverse receptors. Importantly, treatment with antigen-specific Tregs is capable of reversing diabetes in the non-obese diabetic (NOD) mouse model of T1D. Likewise, these Tregs have also been shown to be important in preventing tissue rejection in the transplantation setting. Thus, Treg specificity determined by the T cell receptor can be exploited to selectively suppress a particular component of an ongoing immune response. The translation of this knowledge requires a robust means to generate a large number of patient-derived antigen-specific Tregs. The goal of this proposal is to test the hypothesis that the introduction of antigen-specific Tregs will be able to correct the initiating and persistent autoimmunity in T1D, as well as prevent the transplant-mediated destruction of beta-cells following stem cell transplantation. Thus, we propose to develop engineered tissue-directed human regulatory T cells capable of suppressing autoimmune and transplant-related destruction of beta-cells. To generate these cells we will deliver the specific T cell receptors (TCRs) by gene therapy delivery mechanisms to a patient’s own Treg population and test their ability to suppress specific immune responses in immunodeficient mice following beta-cell replacement therapies.
Statement of Benefit to California: 
Type 1 diabetes (T1D), previously referred to as Juvenile Diabetes, is a chronic condition that leads to devastating consequences for patients and places a huge financial burden on the California health care system. T1D occurs as a consequence of the systematic immune destruction of the insulin-producing beta cells in the pancreas. Once those cells are destroyed, the production of insulin is dramatically compromised and patients lose the ability to control blood sugar levels. Chronic periods of elevated blood sugar result in numerous secondary complications including heart disease, blindness, kidney failure, and abnormal nervous system function, among others. There is currently no known way to prevent T1D. According to the California Department of Public Health, there were 2.7 million Californians with diabetes in 2007, meaning that 1 out 10 adult Californians has diabetes. Of these, approximately 5-10% of patients have T1D, with the remainder consisting of patients with insulin-resistant type 2 diabetes. Of particular concern, the incidence rate of T1D has been increasing, particularly in children 5 years old and under. T1D is the second most common chronic disease in children, second only to asthma. Consequently T1D, and improved therapeutic approaches for this disease, are issues of great importance to the people of California. Intensive insulin therapy is the only current treatment for T1D. While effective at reducing blood sugar levels in the short term, insulin therapy does not address the underlying autoimmune attack which leads to T1D. Our studies will explore the potential use of human embryonic stem cells to restore insulin-producing cells. In addition, we are exploring ways to genetically modify (through the use of gene therapy) a population of regulatory cells (Tregs) within the immune system to stop the autoimmune attack that initiates T1D. We expect that these modified Tregs will not only stop the autoimmune process, but will also protect against the immune attack which normally arises against the transplanted tissues and any stem cell-derived tissues. We hope to eventually use these procedures to treat patients with T1D. If successful, our results may allow patients with T1D to discontinue, or greatly reduce the amount of insulin they must currently take to maintain normal blood sugar levels. This approach will directly benefit those with T1D, as well as the general population by reducing the health care burden associated with the care of this chronic disease.
Progress Report: 
  • Type 1 diabetes (T1D) is caused by the destruction of insulin producing b-cells in the pancreatic islets by an overactive self immune system. Due to lack of ways of preventing T1D, insulin administration is currently most common method of treatment, but susceptible to developing serious, long-term complications. Islet transplantation provides an excellent alternative and can improve glycemic control and reduce the risk of further complications associated with diabetes. Transplantation of pancreas or isolated islets across immune barriers has been conducted with some efficacy but is limited by inadequate organ availability and the need for long-term non-specific immunosuppression. The ability to transplant a renewable supply of islets or β-cells would have a dramatic impact on the disease. Human embryonic stem cells (hESC) represent one of the most promising alternative sources of β-cells, given their pluripotent and self-renewing properties. However, we hypothesized that the immunocompetent recipients will recognize the product as foreign (and autoimmune-self) due to MHC-mismatch (allogeneic) between donor and recipient, leading to transplant rejection. Thus, in order to make stem cell-derived islet cell therapy both commercially and clinically viable, β-cell protective therapies need to be developed to combat the strong allogeneic immune response, as well as the recurrent autoimmune attack which caused the disease in the first place.
  • In previous studies, we have shown that a small population of CD4+ regulatory T cells (Tregs) plays a critical role in controlling self-reactivity thus maintaining immune tolerance. Adoptive immunotherapy with Tregs into diabetes prone non-obese diabetic (NOD) mice can restore immune tolerance leading to a long-term cure of T1D and have shown a lot of promise for the treatment of autoimmune diseases in the preclinical studies. A key parameter has been the enhanced activity of antigen specificity in directing the tissue-protective functions of Tregs. Thus, in this proposal, we proposed to exploit antigen-specific Treg to selectively regulate ongoing immune responses while avoiding the need for pan-immunosuppression. In the past year, we have made significant, albeit slow progress in this effort. We have taken significant steps to develop an approach to expand alloantigen-specific Tregs (those that recognize and suppress immune responses against foreign tissues) from patients with T1D. We have cloned and expressed self-antigen-specific T cell receptor genes in expanded Tregs to determine their ability to suppress stem cell-derived islet transplants. We have established a humanized mouse model to test the hypothesis that engineered antigen-specific Tregs will potently suppress rejection of stem cells. We set up a mouse model of islet transplantation by implanting human islets (from cadavers) in mice lacking a functional immune system. These islets were functional and produced insulin to control normal glucose levels in mice. However, when these mice were complemented with human immune system, the islet grafts were rejected by the allogeneic immune response. This provides an excellent mimic to the human islet transplant where a similar allogeneic immune response leads to the graft rejection. This will provide a setting for testing the engineered Tregs. More over, we have shown that self-antigen and alloreactive Tregs can be generated and transferred in to this humanized mouse setting. Unfortunately, we were unable to test the stem cell-derived islets in this setting as yet due to unexpected challenges in our efforts to produce these cells due to technical problems. However, significant progress has been made to rectify these problems and we are confident that we will succeed in using stem cell-derived islets in the coming year.
  • Type 1 diabetes (T1D) is caused by the destruction of insulin producing b-cells in the pancreatic islets by an overactive self immune system. Due to lack of ways of preventing T1D, insulin administration is currently most common method of treatment, but susceptible to developing serious, long-term complications. Islet transplantation provides an excellent alternative and can improve glycemic control and reduce the risk of further complications associated with diabetes. Transplantation of pancreas or isolated islets across immune barriers has been conducted with some efficacy but is limited by inadequate organ availability and the need for long-term non-specific immunosuppression. The ability to transplant a renewable supply of islets or β-cells would have a dramatic impact on the disease. Human embryonic stem cells (hESC) represent one of the most promising alternative sources of β-cells, given their pluripotent and self-renewing properties. However, we hypothesized that the immunocompetent recipients will recognize the product as foreign (and autoimmune-self) due to MHC-mismatch (allogeneic) between donor and recipient, leading to transplant rejection. Thus, in order to make stem cell-derived islet cell therapy both commercially and clinically viable, β-cell protective therapies need to be developed to combat the strong allogeneic immune response, as well as the recurrent autoimmune attack which caused the disease in the first place.
  • In previous studies, we have shown that a small population of CD4+ regulatory T cells (Tregs) plays a critical role in controlling self-reactivity thus maintaining immune tolerance. Adoptive immunotherapy with Tregs into diabetes prone non-obese diabetic (NOD) mice can restore immune tolerance leading to a long-term cure of T1D and have shown a lot of promise for the treatment of autoimmune diseases in the preclinical studies. A key parameter has been the enhanced activity of antigen specificity in directing the tissue-protective functions of Tregs. Thus, in this proposal, we proposed to exploit antigen-specific Treg to selectively regulate ongoing immune responses while avoiding the need for pan-immunosuppression. In the past year, we have made significant, albeit slow progress in this effort. We have taken significant steps to develop an approach to expand alloantigen-specific Tregs (those that recognize and suppress immune responses against foreign tissues). We have developed a process for isolating and expanding alloantigen-specific Tregs to determine their ability to suppress stem cell-derived islet transplants. We have established a humanized mouse model to test the hypothesis that alloantigen-specific Tregs will potently suppress rejection of stem cells. We set up a mouse model of islet transplantation by implanting human islets (from cadavers) in mice lacking a functional immune system. These islets were functional and produced insulin to control normal glucose levels in mice. However, when these mice were complemented with human immune system, the islet grafts were rejected by the allogeneic immune response. This provides an excellent mimic to the human islet transplant where a similar allogeneic immune response leads to the graft rejection. This will provide a setting for testing the allospecific Tregs.
  • This year we have begun to test the stem cell-derived islets in this setting. First, we have developed a more efficient and effective protocol for developing pancreatic endoderm from human embryonic stem cells. These cells have been transferred into immunodeficient mice and shown to produce human insulin after some period of time (3 months). In addition, we have developed in vitro modifications of the differentiation process that has enabled the formation of cells that express markers of fully matured insulin producing cells without extensive in vivo maturation whose functionality is currently assessed. Finally, we have been able to mimic this process using a genetically marked ES population (luciferase transduced). This allows for rapid and ongoing analysis of cell survival in transplanted animals to enable rapid and extensive therapeutic interventions.
  • Finally, we have validated a humanized mouse model that allows an analysis of alloreactive Tregs in this setting. Thus, in the coming year, we fully expect to be able to test the hypotheses posed in the original application, as all the tools are now available. In addition, we will work towards adapting the process to the analysis of iPS cells.
  • The goal of this project was to using novel immune techniques to block rejection of human ES cell derived islet precursors in mouse models of diabetes. during the past three years, we identified and developed islet specific regulatory T cells that could be used to suppress immune responses to the stem cell-derived islets. we also established, with some difficulty, a more robust methodology to direct the differentiation of human ES cells into islet precursors for transplantation. the studies were not complete but demonstrated in proof of principle studies that the tools can be generated to address the primary questions posed in this project.

Endodermal differentiation of human ES cells

Funding Type: 
SEED Grant
Grant Number: 
RS1-00308
ICOC Funds Committed: 
$635 242
Disease Focus: 
Diabetes
Stem Cell Use: 
Embryonic Stem Cell
oldStatus: 
Closed
Public Abstract: 
The goals of this proposal are to investigate endodermal differentiation and proliferation in human ES cell cultures. Endodermal cells give rise to the epithelial lining of the respiratory and digestive tract as well as to the liver and pancreas. The future treatment of diseases such as type I diabetes using stem cell therapy relies on our ability to differentiate stem cells into endoderm, a prerequisite step to forming pancreatic beta cells. In 2005, D’Amour et al. reported the efficient differentiation of human ES cells into endoderm. This report provides a potentially effective protocol that needs to be further evaluated (specific aim 1). In addition, given that the success of stem-cell therapy depends on our ability to generate large numbers of differentiated cells (e.g. 200-700 million beta cells per patient are currently being used in the Edmonton protocol), we will investigate the ability of the endodermal generated in specific aim 1 cells to proliferate in culture (specific aim 2).
Statement of Benefit to California: 
Stem cell therapy relies on the development of efficient and reproducible protocols to differentiate stem cells into various cell types such as pancreatic beta cells. The first step to making pancreatic beta cells is the differentiation of stem cells into so-called endodermal cells, one of the 3 basic cell types of the body. In addition, in order to make stem cell therapy a viable option, one needs to be able to generate large numbers of differentiated cells from stem cells. Our proposal aims to establish such protocols. The health of California and its citizens will ultimately benefit from this research as it will help develop stem cell therapies.
Progress Report: 
  • The goals of this proposal are to investigate endodermal differentiation and proliferation of human ES cells in culture. Endodermal differentiation is a necessary step towards making pancreatic beta cells, as well as other endodermal cells such as liver cells. Pancreatic beta cells generated from human ES cells could be used to treat type I diabetics. In the past two years, we have incorporated human ES cell culture technology into our laboratory and have been able to replicate data obtained by other research groups. While several other research groups and companies around the world are focused on making pancreatic beta cells as quickly as possible, we strongly believe that a more detailed understanding of the biology of human ES cell differentiation into endoderm will help the optimization of this protocol. Therefore, we have focused our efforts on testing a number of variables in the initial step of creating definitive endoderm. We have found that different human ES cell lines have very different capacity to differentiate into endoderm under the same culture conditions. In addition, we have recently focused our research effort on the post-translational modifications of key regulators of endoderm differentiation, and found a critical role for a poorly appreciated modification, namely a sugar modification called GlcNAcylation. In summary, developing a reproducible and efficient way to differentiate human ES cells into endoderm, as well as a thorough understanding of this key step, will allow us and others to elucidate the detailed set of molecular and biochemical events underlying this critical differentiation step, and will improve differentiation protocols.
  • The goals of this proposal are to investigate endodermal differentiation and proliferation of human ES cells in culture. Endodermal differentiation is a necessary step towards making pancreatic beta cells, as well as other endodermal cells, such as liver cells. Pancreatic beta cells generated from human ES cells could be used to treat type I diabetes. In the past two years, we have incorporated human ES cell culture technology into our laboratory and have been able to replicate data obtained by other research groups. While several other research groups and companies around the world are focused on making pancreatic beta cells as quickly as possible, we strongly believe that a more detailed understanding of the biology of human eS cell differentiation into endoderm will help the optimization of this protocol. Therefore, we have focused our efforts on testing a number of variables in the initial step of creating definitive endoderm. We have found that different human ES cell lines have very different capacity to differentiate into endoderm under the same culture conditions. IN addition, we have recently focused our research effort on the post-translational modifications of key regulators of endoderm differentiation, and found a critical role for a poorly appreciated modification—namely a sugar modification called GlcNAcylation. In summary, developing a reproducible and efficient way to differentiate human ES cells into endoderm, as well as thorough understanding of this key step, will allow us and others to elucidate the detailed set of molecular and biochemical events underlying this critical differentiation step, and will improve differentiation protocols.
  • We initiated a project on the role of post-translational modifications during hES cell differentiation into endodermal lineages, specifically on the GlcNAcylation sugar modification. We found that this modification appears to be important for endoderm formation in hES cell cultures. Identification of modified proteins is an important next step in understanding the mechanisms of this phenomenon and may ultimately provide a basis to develop assays for screening drugs that enhance endoderm/beta-cell formation.

Cell Therapy for Diabetes

Funding Type: 
Disease Team Research I
Grant Number: 
DR1-01423
ICOC Funds Committed: 
$22 999 937
Disease Focus: 
Diabetes
Collaborative Funder: 
JDRF
Stem Cell Use: 
Embryonic Stem Cell
Cell Line Generation: 
Embryonic Stem Cell
oldStatus: 
Active
Public Abstract: 
Diabetes exacts a tremendous toll on patients, their families, and society in general. Autoimmune Type 1 diabetes, often called juvenile-onset diabetes, is caused by a person’s own immune system mistakenly destroying their insulin-producing cells in the pancreas, known as beta cells. When those beta cells are lost, the ability to produce insulin in response to food intake is lost, and blood sugar can increase to toxic levels. Although not due to autoimmunity, Type 2 diabetics often lose their ability to produce insulin as well. While pharmaceutical insulin is commonly used to control both types of diabetes, it does not sufficiently replace beta cells, and the adverse short- and long-term effects of diabetes remain, including dangerous episodes of low blood sugar, nerve damage, blindness, kidney damage, foot ulcers leading to amputations, and cardiovascular disease. Ideally, one would like to replace lost beta cells, and attempts to do so have included the use of pancreatic transplants, beta cell (islet) transplants, and transplants of animal cells or tissues. Unfortunately, those approaches are hindered by 1) the limited amount of donor tissue available, and 2) issues regarding immunological complications between donors and recipients. To solve the first problem, the Diabetes Disease Team applying for this CIRM award has developed methods to make replacement beta cells from human embryonic stem cells (hESC), which can be reliably grown in large-scale batches. The hESC-derived beta cells have been shown to cure experimental diabetes in mice and rats. Regarding the issue of donor-recipient compatibility, the Team has had initial success with several strategies, including administering the cells inside a simple device, implantable under the skin, as well as next-generation pharmaceuticals that enable transplantation between unmatched individuals without major side effects. With the critical proof-of-concept milestones behind us, the Team now needs to perform all of the manufacturing and laboratory testing required to assure reliable production of a safe and effective product, thereby generating the data needed to seek FDA approval to test the product in humans. The project engages over 30 scientists and physicians, as well as numerous associates and technicians, whose expertise covers all of the critical areas from process development and manufacturing to clinical testing of novel biomedical products. The proposal includes active project management, and regulatory and ethical oversight. The Team has well defined time lines and milestones to advance the candidate product to an FDA submission. If successful, testing in diabetic patients could begin as early as 3 years from the project initiation.
Statement of Benefit to California: 
Diabetes mellitus currently afflicts more than 250 million people worldwide, with projections of 380 million by the year 2030 (source: International Diabetes Federation). In 2007, there were an estimated 2.7 million Californians with diabetes (source: California Diabetes Program, California Department of Public Health). Further, the disease disproportionately affects certain minority groups and the elderly. Despite the use of insulin and advances in its delivery, the human cost of diabetes is underscored by the financial costs to society: tens of billions of dollars each year in California alone. The primary cause of Type 1 diabetes, and contributing significantly to Type 2 diabetes as well, is the loss of insulin-producing pancreatic beta cells. The proposed Disease Team will develop a beta cell replacement therapy for diabetes. If successful, the therapy will go beyond insulin function, and will perform the full array of normal beta cell functions, including responding in a more physiological manner than manual or mechanized insulin administration. Because they will be more physiological, the replacement cells should also reduce the long-term effects of diabetes. Moreover, the cell therapy will alleviate patients of the constant monitoring of blood glucose and painful insulin injections. For these reasons, it is possible that the product could transform the diabetes treatment landscape and replace pharmaceutical insulin in the market. This product will be available in California first, through clinical trials, and if approved by the FDA for commercial production, could eventually help hundreds of thousands of diabetic Californians. The product will substantially increase quality of life for diabetics and significantly reduce the health care burden in the state. The Team will employ various Californian physicians and scientists, and success of the Team will generate positive recognition for the state. Lastly, once commercially marketed, the product will yield additional jobs in manufacturing, sales, and related industries, and generate revenue for California. Given the market need and the clear feasibility, the product could become the most significant stem cell-based medical treatment of the coming decade, and that would be a great achievement for California, its taxpayers, and CIRM.
Progress Report: 
  • The CIRM Diabetes Disease Team is developing a cell therapy to treat insulin-dependent diabetes. The ultimate goal under CIRM Award DR1-01423 is to file an IND with the FDA to allow first-in-human clinical testing of the cell therapy product. To reach that goal, numerous research and development activities need to be successfully executed in parallel, and the project requires careful planning and agile management. This is particularly critical because the planned product is complex and, as a cutting-edge technology, extends into new regulatory territory. In Year 1 of this Award, virtually all aspects of the project remained on track and the 4-year time line to filing an IND remains the same.
  • The planned product is a combination therapy that is expected to alleviate a diabetic’s need to perform frequent blood monitoring and insulin injections. It will essentially replace or provide needed support to the endocrine pancreas that is lost or damaged in diabetes. The product consists of a human pancreatic progenitor cell population administered in a durable delivery device. Following administration, the progenitor cells mature into human pancreatic islets including functional insulin-producing glucose-responsive beta cells. Prototypes of the product have been tested in hundreds of rodents, and in proof-of-concept studies, this cell-device combination has cured rodents of drug-induced diabetes.
  • The pancreatic progenitor cells are manufactured from human embryonic stem (ES) cells through a series of precise steps in cell culture. Using ES cells as starting material allows for the mass production of progenitor cells that will be required if the product is successful, as ES cells are remarkably proliferative while still remaining stable. In Year 1 of the Disease Team Award, frozen cell banks of ES cells were manufactured under Current Good Manufacturing Practice (cGMP), as required to clinically test and commercialize a cell therapy. Additionally in Year 1, the specific details of the pancreatic progenitor cell manufacturing process were finalized, and documentation was put in place to allow cGMP manufacture of pancreatic progenitor cells for future animal and human studies.
  • The cell delivery device is a small flat sealed chamber made from a semi-permeable membrane. The device serves multiple purposes. It is intended to protect the cells from the patient’s immune system, which is particularly important in autoimmune (Type 1) diabetes. It retains the cells at the site of administration for ease of monitoring and possible removal if necessary. Importantly, while cells cannot pass through it, the semi-permeable membrane allows sugars, oxygen, and other nutrients in, to sustain and regulate the islet cells, and allows insulin and other endocrine proteins out, to regulate blood sugar and other metabolic physiology. In Year 1, numerous prototype configurations of the delivery device were tested in animals, and a final configuration was determined. A device manufacturing facility was designed and built. Manufacturing and testing equipment was installed, and documentation put in place for production of clinically compliant devices. As with cell manufacturing described above, device manufacturing can now proceed at a scale and level of quality that will facilitate pre-clinical and clinical testing of the combination product.
  • It is possible that the device alone will not be sufficient to protect the cells from a diabetic patient’s immune system. In anticipation of this possibility, the Diabetes Disease Team includes world-renowned immunologists who are establishing animal models to test and address this question accordingly. Fortunately, there are many pharmaceutical options, including cutting-edge technologies, that have proven effective in protecting transplanted human islets from immune rejection, and those might be applied to administration of this cell therapy product as well. The Disease Team’s clinical group is developing plans for the first-in-human testing and will incorporate a regimen of immune modulation as appropriate. In Year 1, the animal models to test the requirement for immune modulation and various regimens were established. In Year 2, these models will be used to investigate these questions.
  • The CIRM Diabetes Disease Team is developing a cell therapy to treat insulin-dependent diabetes. The ultimate goal under CIRM Award DR1-01423 is to file an IND with the FDA to allow first-in-human clinical testing of the cell therapy product. To reach that goal, numerous research and development activities need to be successfully executed in parallel, and the project requires careful planning and agile management. This is particularly critical because the planned product is complex and, as a cutting-edge technology, extends into new regulatory territory. In Year 2 of this Award, virtually all aspects of the project remained on track and the 4-year time line to filing an IND remains the same.
  • The planned product is a combination therapy that is expected to alleviate diabetes patients’ need to perform frequent blood monitoring and insulin injections. It will essentially replace or provide needed support to the endocrine pancreas that is lost or damaged in diabetes. The product consists of a human pancreatic progenitor cell population administered in a durable delivery device. Following administration, the progenitor cells mature into human pancreatic islets including functional insulin-producing glucose-responsive beta cells. Prototypes of the product have been tested in hundreds of rodents, and in proof-of-concept studies this cell-device combination has cured rodents of drug-induced diabetes.
  • The pancreatic progenitor cells are manufactured from human embryonic stem (ES) cells through a series of precise steps in cell culture. Using ES cells as starting material allows for the mass production of progenitor cells that will be required if the product is successful, as ES cells are remarkably proliferative while still remaining stable. In Year 1 of the Disease Team Award, frozen cell banks of ES cells were manufactured under Current Good Manufacturing Practice (cGMP), as required to clinically test and commercialize a cell therapy. In Year 2, these cGMP ES cell banks were tested to confirm that they performed similarly to previous banks. The cell manufacturing protocol was finalized and several batches of progenitor cells were manufactured to demonstrate the reliability of the protocol, in particular, with the new cGMP ES cells.
  • The cell delivery device is a small flat sealed chamber made from a semi-permeable membrane. The device serves multiple purposes. It is intended to protect the cells from the patient’s immune system, which is particularly important in autoimmune (Type 1) diabetes. It retains the cells at the site of administration for ease of monitoring and possible removal if necessary. Importantly, while cells cannot pass through it, the semi-permeable membrane allows sugars, oxygen, and other nutrients in, to sustain and regulate the islet cells, and allows insulin and other endocrine proteins out, to regulate blood sugar and other metabolic physiology. In Year 1, numerous prototype configurations of the delivery device were tested in animals, and a final configuration was determined. A device manufacturing facility was designed and built. Manufacturing and testing equipment was installed, and documentation put in place for production of clinically compliant devices. In Year 2, several batches of delivery devices were manufactured and tested under development phase-appropriate Quality Systems Regulations. A Good Laboratory Practice (GLP) study of the combination product, comprised of cells and devices manufactured with the newly developed systems, was performed to establish safety and efficacy in mice, prior to human testing. The results of the GLP study were favorable, suggesting the combination product will likely be safe and effective in the clinic.
  • It is possible that the device alone will not be sufficient to protect the cells from a patient’s immune system. In anticipation of this possibility, the Diabetes Disease Team includes world-renowned immunologists who are establishing animal models to test and address this question accordingly. In Year 2, preliminary data were collected using these animal models. The preliminary data suggest that the device will protect cells from autoimmunity.
  • In Year 3, the clinical protocol will be drafted, further refinements to product manufacturing including device loading will be established, and further pre-clinical testing will be performed. The Team plans to present the candidate product and development plans to regulatory agencies in order to obtain valuable feedback. The goal is to establish sufficient pre-clinical assurance to facilitate clinical testing at the end of the 4-year award period.
  • The CIRM Diabetes Disease Team is developing a stem cell-derived cell therapy to treat insulin-dependent diabetes. The ultimate goal under the 4-year CIRM Award DR1-01423 is to file an IND (Investigational New Drug application) with the FDA to allow first-in-human clinical testing of the cell therapy product. To reach this goal, numerous research and development activities need to be successfully executed in parallel. The project requires careful planning and agile management particularly because the planned product is complex and, as a cutting-edge technology, extends into new territory from a regulatory perspective. In Year 3 of this Award, all aspects of the project remained close to the original schedule. One study report from an external Contract Research Organization (CRO) was delivered two months later than planned, which delayed a meeting with the FDA and subsequent downstream activities. Accordingly, two months has been added to the original 4-year time line to filing an IND. The new target for IND filing is March 2014.
  • The planned product is a combination therapy that is expected to alleviate diabetes patients’ need to perform frequent blood monitoring and insulin injections. It will essentially replace or provide needed support to the endocrine pancreas that is lost or damaged in diabetes. The product consists of a human cell population containing pancreatic progenitors administered subcutaneously in a durable delivery device. Following administration, the progenitor cells mature into human pancreatic islet-like tissue including functional insulin-producing, glucose-responsive beta cells while in the device. Prototypes of the product have been tested in hundreds of rodents, and in proof-of-concept studies this cell-device combination has cured rodents of chemically-induced diabetes.
  • The pancreatic cells are manufactured from human embryonic stem (ES) cells through a series of precise steps in cell culture. In Year 3, a Cell Manufacturing Cleanroom was built and commissioned in preparation for manufacturing cells for clinical testing. Two new cell manufacturing formats, both amenable to the scale-up that will be required for commercial manufacturing, were also developed. At the end of Year 3, a Pilot Plant was established for process development and technology transfer of the cell manufacturing protocol.
  • The cell delivery device is essentially a small sealed envelope made from a semi-permeable membrane. It is expected to protect the cells from the patient’s immune system and retain the cells at the site of administration. At the same time it will allow sugars, oxygen, and other nutrients in, to sustain and regulate the islet-like tissue, and allow insulin and other endocrine proteins out, to regulate blood sugar and other metabolic physiology. In Years 1-2, prototype (‘animal-sized’) devices were produced and tested, the configuration was finalized, and a Device Manufacturing Facility with equipment for quality control testing was built. In Year 3, the clinical (‘human-sized’) device was designed and built. Also in Year 3, all ISO10993 (safety standards for medical devices from the International Organization for Standardization) testing was completed, establishing that the device and its component materials will be safe for human use. A prototype system to load the progenitor cells into the device was designed and built in Year 3. The Team established and staffed a Combination Product Group.
  • In Year 3, a GLP (good laboratory practice) study of the combination product to test safety and efficacy in mice, prior to human testing, was completed by an independent CRO. The results were favorable, providing further rationale for advancement of the product into clinical testing.
  • To evaluate the potential of the device to protect the implanted cells from a patient’s immune system, the Diabetes Disease Team includes world-renowned immunologists who are establishing animal models to test and address this question. In Year 3, animal studies demonstrated that the device indeed protects animal cells from allo-immunity (addressing differences between donor and recipient tissues), suggesting the human pancreatic cells will also be protected in the product planned for human use.
  • In Year 3, the Team met with the FDA in a Pre-IND meeting. This meeting was informative and provided clarity on the remaining activities before an IND can be submitted and a clinical trial initiated.
  • During Years 1-3, the clinical protocol was drafted, and in Year 4 it will be finalized while the clinical sites are prepared. Also in Year 4, refinements to product manufacturing including device loading will be established, and additional pre-clinical testing will be performed to further assure safety of all aspects of the clinical plan. The goal is to establish a body of pre-clinical data that supports clinical testing at the end of the 4-year award period.

Generation of a functional thymus to induce immune tolerance to stem cell derivatives

Funding Type: 
Basic Biology V
Grant Number: 
RB5-07262
ICOC Funds Committed: 
$1 191 000
Disease Focus: 
Immune Disease
HIV/AIDS
Diabetes
Stem Cell Use: 
Embryonic Stem Cell
Cell Line Generation: 
Embryonic Stem Cell
oldStatus: 
Closed
Public Abstract: 
Stem cell research offers the promise of replacing missing or damaged tissues in the treatment of disease. Stem-cell-derived transplants still face problems with rejection as in traditional organ transplants. Several drugs can prevent rejection but also suppress the immune system, leaving patients vulnerable to infections and cancer. To avoid rejection without using drugs requires re-educating the immune system to “tolerate” the transplant and not see it as foreign. Because of its role in educating developing immune cells, the thymus is a critical organ in establishing what the immune system recognizes as “self” and not foreign, in a process known as immune tolerance. By growing a new thymus from stem cells matched to transplanted tissues, we can condition the immune system to be tolerant to the transplant and avoid chronic immunosuppression. We have developed a method to grow stem cells into thymic cells that become normal thymus tissue when grafted into mouse models. Notably, the new thymus can promote normal development of immune cells, indicating the potential for generating new, tolerant immune cells. We propose to induce immune tolerance to other stem-cell derived tissues using stem-cell-derived thymus tissue to engineer tolerance. We will optimize our methods of growing thymus tissue, which will be used to condition mice to accept stem-cell-derived pancreas grafts, testing their ability both to prevent rejection and to cure diabetes in a transplant model.
Statement of Benefit to California: 
The proposed work aims to improve the effectiveness of stem cell treatments by preventing immunological rejection of transplanted tissue derived from stem cells. An important barrier to the clinical use of stem-cell-derived organs and tissues is the potential of the immune system to reject or damage this regenerated tissue. Improved approaches to address immune rejection are needed since stem cell therapies are underway in treating diseases that have a wide impact on the health of Californians, including diabetes, Parkinson’s disease, Alzheimer’s disease, retinal eye diseases, and musculoskeletal diseases. The proposed studies will improve treatment for these diseases by providing a novel method to halt immunologic rejection or destruction of tissues that are derived from stem cells. We have successfully developed methods to grow thymus tissue, which controls the ability of the immune system to be “tolerant” of transplanted tissue. Here we will improve methods to generate thymus from stem cells and show that it can promote survival of transplanted tissue derived from the same cells. By using the thymus to condition the immune system towards tolerance, we hope to avoid immune rejection without the use of immunosuppressive drugs. Induction of a tolerant immune system in this way would represent a significant advance in improving stem cell therapies. Thus, this work could have a broad impact on a large number of the disease treatments that involve stem cells.

Preclinical and clinical testing of a stem cell-based combination product for insulin-dependent diabetes

Funding Type: 
Strategic Partnership I
Grant Number: 
SP1-06513
Investigator: 
ICOC Funds Committed: 
$10 075 070
Disease Focus: 
Diabetes
Stem Cell Use: 
Embryonic Stem Cell
oldStatus: 
Active
Public Abstract: 
Diabetes exacts a tremendous toll on patients, their families, and society. Autoimmune Type 1 diabetes, often called juvenile-onset diabetes, is caused by a person’s own immune system mistakenly destroying their insulin-producing cells in the pancreas, known as beta cells. When those beta cells are lost, the ability to produce insulin in response to consumed carbohydrates is lost, and blood sugar can increase to toxic levels. Although not due to autoimmunity, Type 2 diabetics often lose their ability to produce insulin as well. While pharmaceutical insulin is commonly used to control both types of diabetes, it is difficult to self-administer optimally, does not sufficiently replace beta cells, and the adverse short- and long-term effects of diabetes and risks associated with insulin usage remain, including potentially fatal hypoglycemic episodes, nerve damage, blindness, kidney failure, foot ulcers / amputations, and heart disease. Ideally, one would like to replace lost beta cells, and attempts to do so have included the use of pancreas transplants, beta cell (islet) transplants, and transplants of animal cells. Unfortunately, those approaches are hindered by 1) a limited amount of donor tissue, and 2) issues regarding immunological incompatibility between donors and recipients. To solve the first problem, the group applying for this CIRM award has developed methods to make replacement beta cells from human embryonic stem cells (hESC), which can be reliably grown in large-scale batches. The hESC-derived beta cells have been shown to cure experimental diabetes in mice and rats. Regarding the issue of donor-recipient compatibility, the group has found that the cells can be administered under the skin in a simple device, essentially an envelope made of semi-permeable membrane, which is intended to protect the implanted cells from the patient’s immune system. Upon implant, the cell-loaded device, which also keeps the implanted cells in place, acquires its own dedicated circulation. This blood supply provides oxygen and nutrients to the implanted cells, and also allows them to respond to blood sugar by releasing pancreatic hormones such as insulin into the circulation. Thus, the implanted cell-loaded device in essence represents a “replacement endocrine pancreas” with its own protection from autoimmunity. This product could return a patient's blood sugar regulation to normal and alleviate both the day-to-day and long-term issues of diabetes. The group has made tremendous progress in moving the product from concept through years of research and development. At this point an array of detailed work on the exact format to be tested in humans needs to be completed and submitted to the FDA on the way to clinical trials. The proposed award would provide critical funding, including potentially triggering matching funding from a large corporate partner, to advance the product through the first-in-human testing which will be very informative.
Statement of Benefit to California: 
Diabetes mellitus currently afflicts approximately 350 million people worldwide, with projections of over 500 million by the year 2030 (sources: World Health Organization; International Diabetes Federation). In the year 2000 there were an estimated 2,089,657 cases of diabetes in California (diagnosed + undiagnosed; source: Diabetes Control Program, California Department of Health Services). Further, the disease disproportionately affects certain minority groups and the elderly. Despite the use of insulin and advances in its delivery, the human cost of diabetes is underscored by the financial costs to society: tens of billions of dollars each year in California alone. The primary cause of Type 1 diabetes, and contributing significantly to Type 2 diabetes as well, is the loss of insulin-producing pancreatic beta cells. The proposed Partnership will develop a beta cell replacement therapy for insulin-dependent diabetes. If successful, the therapy will go beyond insulin function, and will perform the full array of normal beta cell functions, including responding in a more physiological manner than manual or mechanized insulin administration. Because they will be more physiological, the replacement cells should also reduce the long-term effects of diabetes. Moreover, the cell therapy will alleviate patients of the constant monitoring of blood glucose and painful insulin injections. For these reasons, it is possible that the product could transform the diabetes treatment landscape dramatically and even replace pharmaceutical insulin in the market. This product will be available in California first, through clinical testing, and if approved by the FDA for commercial production, will eventually help hundreds of thousands of Californians with diabetes. The product will substantially increase quality of life for patients and their families while significantly reducing the health care burden in the state. The proposed Partnership will employ Californian doctors and scientists, and success will generate accolades and notoriety for the state. Lastly, once commercially marketed, the product will yield additional jobs in manufacturing, sales, and related industries, and generate revenue for California. Given the market need and the clear feasibility, the product could become the most significant stem cell-based medical treatment of the coming decade, and that will be a great achievement for California, its taxpayers, and CIRM.

Engineered matrices for control of lineage commitment in human pancreatic stem cells

Funding Type: 
Basic Biology V
Grant Number: 
RB5-07398
ICOC Funds Committed: 
$526 896
Disease Focus: 
Diabetes
Cell Line Generation: 
Adult Stem Cell
oldStatus: 
Closed
Public Abstract: 
Patients with end-stage type 1 diabetes (T1D) can be effectively managed by allogeneic islet transplantation. However, a severe cadaveric organ shortage greatly limits use of this promising procedure. Stem cells have the potential to provide a solution to this bottleneck because of their ability to self-renew and differentiate into islet β-cells. Although progress has been made in coaxing human embryonic stem (ES) cells to differentiate into pancreatic progenitor-like cells in culture, there are safety concerns regarding ES cell-derived products because of their ability to form teratomas in vivo. In contrast, adult tissue cells lack teratoma potential. Our goal is to develop, for transplantation, insulin-expressing cells derived from adult human pancreatic progenitor-like cells. If successful, the proposed research will establish a new paradigm for the development of cell products derived from adult pancreata and enable important advances in cell replacement therapy for T1D. This research will allow human cadaveric adult pancreatic tissues, which are largely discarded after islet isolation, to be used to maximum efficiency in transplantation. Moreover, the results of these studies will be applicable to the treatment of end-stage type 2 diabetes patients, in whom islet β-cells are exhausted and dysfunctional.
Statement of Benefit to California: 
In type 1 and some type 2 diabetic patients, the pancreatic β-cells, which secrete insulin in response to elevated glucose concentrations in the blood, are insufficient or dysfunctional. Insulin injection is the most common form of therapy to control diabetes. However, insulin injection cannot match the physiological response conferred by endogenous β-cells, and complications inevitably develop over time. Allogeneic islet transplantation is beneficial to those diabetic patients who have developed end-stage complications. However, it is estimated that fewer than 1% of Californians most in need of islet transplantation can benefit from the procedure because there is a severe shortage of human cadaveric pancreas organs. This dire situation has led to the search for alternative sources of β-cells for transplantation. If human adult pancreatic stem and progenitor cells can be coaxed to differentiate into β-like cells in culture, they would provide large numbers of cells for replacement therapy. This proposal addresses the important challenge of producing β-cells through differentiation of human pancreatic stem and progenitor cells, with the ultimate objective of developing new treatments for diabetic patients.

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