Heart Disease

Coding Dimension ID: 
295
Coding Dimension path name: 
Heart Disease

Antibody tools to deplete or isolate teratogenic, cardiac, and blood stem cells from hESCs

Funding Type: 
Tools and Technologies II
Grant Number: 
RT2-02060
ICOC Funds Committed: 
$1 869 487
Disease Focus: 
Blood Disorders
Heart Disease
Liver Disease
Stem Cell Use: 
Embryonic Stem Cell
iPS Cell
oldStatus: 
Active
Public Abstract: 
Purity is as important for cell-based therapies as it is for treatments based on small-molecule drugs or biologics. Pluripotent stem cells possess two properties: they are capable of self regeneration and they can differentiate to all different tissue types (i.e. muscle, brain, heart, etc.). Despite the promise of pluripotent stem cells as a tool for regenerative medicine, these cells cannot be directly transplanted into patients. In their undifferentiated state they harbor the potential to develop into tumors. Thus, tissue-specific stem cells as they exist in the body or as derived from pluripotent cells are the true targets of stem cell-based therapeutic research, and the cell types most likely to be used clinically. Existing protocols for the generation of these target cells involve large scale differentiation cultures of pluripotent cells that often produce a mixture of different cell types, only a small fraction of which may possess therapeutic potential. Furthermore, there remains the real danger that a small number of these cells remains undifferentiated and retains tumor-forming potential. The ideal pluripotent stem cell-based therapeutic would be a pure population of tissue specific stem cells, devoid of impurities such as undifferentiated or aberrantly-differentiated cells. We propose to develop antibody-based tools and protocols to purify therapeutic stem cells from heterogeneous cultures. We offer two general strategies to achieve this goal. The first is to develop antibodies and protocols to identify undifferentiated tumor-forming cells and remove them from cultures. The second strategy is to develop antibodies that can identify and isolate heart stem cells, and blood-forming stem cells capable of engraftment from cultures of pluripotent stem cells. The biological underpinning of our approach is that each cell type can be identified by a signature surface marker expression profile. Antibodies that are specific to cell surface markers can be used to identify and isolate stem cells using flow cytometry. We can detect and isolate rare tissue stem cells by using combinations of antibodies that correspond to the surface marker signature for the given tissue stem cell. We can then functionally characterize the potential of these cells for use in regenerative medicine. Our proposal aims to speed the clinical application of therapies derived from pluripotent cell products by reducing the risk of transplanting the wrong cell type - whether it is a tumor-causing residual pluripotent cell or a cell that is not native to the site of transplant - into patients. Antibodies, which exhibit exquisitely high sensitivity and specificity to target cellular populations, are the cornerstone of our proposal. The antibodies (and other technologies and reagents) identified and generated as a result of our experiments will greatly increase the safety of pluripotent stem cell-derived cellular therapies.
Statement of Benefit to California: 
Starting with human embryonic stem cells (hESC), which are capable of generating all cell types in the body, we aim to identify and isolate two tissue-specific stem cells – those that can make the heart and the blood – and remove cells that could cause tumors. Heart disease remains the leading cause of mortality and morbidity in the West. In California, 70,000 people die annually from cardiovascular diseases, and the cost exceeded $48 billion in 2006. Despite major advancement in treatments for patients with heart failure, which is mainly due to cellular loss upon myocardial injury, the mortality rate remains high. Similarly, diseases of the blood-forming system, e.g. leukemias, remain a major health problem in our state. hESC and induced pluripotent stem cells (collectively, pluripotent stem cells, or PSC) could provide an attractive therapeutic option to treat patients with damaged or defective organs. PCS can differentiate into, and may represent a major source of regenerating, cells for these organs. However, the major issues that delay the clinical translation of PSC derivatives include lack of purification technologies for heart- or blood-specific stem cells from PSC cultures and persistence of pluripotent cells that develop into teratomas. We propose to develop reagents that can prospectively identify and isolate heart and blood stem cells, and to test their functional benefit upon engraftment in mice. We will develop reagents to identify and remove residual PSC, which give rise to teratomas. These reagents will enable us to purify patient-specific stem cells, which lack cancer-initiating potential, to replenish defective or damaged tissue. The reagents generated in these studies can be patented forming an intellectual property portfolio shared by the state and the institutions where the research is carried out. The funds generated from the licensing of these technologies will provide revenue for the state, will help increase hiring of faculty and staff (many of whom will bring in other, out-of-state funds to support their research) and could be used to ameliorate the costs of clinical trials – the final step in translation of basic science research to clinical use. Only California businesses are likely to be able to license these reagents and to develop them into diagnostic and therapeutic entities; such businesses are at the heart of the CIRM strategy to enhance the California economy. Most importantly, this research will set the platform for future stem cell-based therapies. Because tissue stem cells are capable of lifelong self-renewal, stem cell therapies have the potential to be a single, curative treatment. Such therapies will address chronic diseases with no cure that cause considerable disability, leading to substantial medical expense. We expect that California hospitals and health care entities will be first in line for trials and therapies. Thus, California will benefit economically and it will help advance novel medical care.
Progress Report: 
  • Our program is focused on improving methods that can be used to purify stem cells so that they can be used safely and effectively for therapy. A significant limitation in translating laboratory discoveries into clinical practice remains our inability to separate specific stem cells that generate one type of desired tissue from a mixture of ‘pluripotent’ stem cells, which generate various types of tissue. An ideal transplant would then consist of only tissue-specific stem cells that retain a robust regenerative potential. Pluripotent cells, on the other hand, pose the risk, when transplanted, of generating normal tissue in the wrong location, abnormal tissue, or cancer. Thus, we have concentrated our efforts to devise strategies to either make pluripotent cells develop into desired tissue-specific stem cells or to separate these desired cells from a mixture of many types of cells.
  • Our approach to separating tissue-specific stem cells from mixed cultures is based on the theory that every type of cell has a very specific set of molecules on its surface that can act as a signature. Once this signature is known, antibodies (molecules that specifically bind to these surface markers) can be used to tag all the cells of a desired type and remove them from a mixed population. To improve stem cell therapy, our aim is to identify the signature markers on: (1) the stem cells that are pluripotent or especially likely to generate tumors; and (2) the tissue-specific stem cells. By then developing antibodies to the pluripotent or tumor-causing cells, we can exclude them from a group of cells to be transplanted. By developing antibodies to the tissue-specific stem cells, we can remove them from a mixture to select them for transplantation. For the second approach, we are particularly interested in targeting stem cells that develop into heart (cardiac) tissue and cells that develop into mature blood cells. As we develop ways to isolate the desired cells, we test them by transplanting them into animals and observing how they grow.
  • Thus, the first goal of our program is to develop tools to isolate pluripotent stem cells, especially those that can generate tumors in transplant recipients. To this end, we tested an antibody aimed at a pluripotent cell marker (stage-specific embryonic antigen-5 [SSEA-5]) that we previously identified. We transplanted into animals a population of stem cells that either had the SSEA-5-expressing cells removed or did not have them removed. The animals that received the transplants lacking the SSEA-5-expressing cells developed smaller and fewer teratomas (tumors consisting of an abnormal mixture of many tissues). Approaching the problem from another angle, we analyzed teratomas in animals that had received stem cell transplants. We found SSEA-5 on a small group of cells we believe to be responsible for generating the entire tumor.
  • The second goal of the program is to develop methods to selectively culture cardiac stem cells or isolate them from mixed cultures. Thus, in the last year we tested procedures for culturing pluripotent stem cells under conditions that cause them to develop into cardiac stem cells. We also tested a combination of four markers that we hypothesized would tag cardiac stem cells for separation. When these cells were grown under the proper conditions, they began to ‘beat’ and had electrical activity similar to that seen in normal heart cells. When we transplanted the cells with the four markers into mice with normal or damaged hearts, they seemed to develop into mature heart cells. However, these (human) cells did not integrate with the native (mouse) heart cells, perhaps because of the species difference. So we varied the approach and transplanted the human heart stem cells into human heart tissue that had been previously implanted in mice. In this case, we found some evidence that the transplanted cells differentiated into mature heart cells and integrated with the surrounding human cells.
  • The third goal of our project is to culture stem cells that give rise only to blood cells and test them for transplantation. In the past year, we developed a new procedure for treating cultures of pluripotent stem cells so that they differentiate into specific stem cells that generate blood cells and blood vessels. We are now working to refine our understanding and methods so that we end up with a culture of differentiated stem cells that generates only blood cells and not vessels.
  • In summary, we have discovered markers and tested combinations of antibodies for these markers that may select unwanted cells for removal or wanted cells for inclusion in stem cell transplants. We have also begun to develop techniques for taking a group of stem cells that can generate many tissue types, and growing them under conditions that cause them to develop into tissue-specific stem cells that can be used safely for transplantation.
  • Our program is focused on improving methods to purify blood-forming and heart-forming stem cells so that they can be used safely and effectively for therapy. Current methods to identify and isolate blood-forming stem cells from bone marrow and blood are efficient. In addition, we found that if blood-forming stem cells are transplanted, they create in the recipient an immune system that will tolerate (i.e., not reject) organs, tissues, or other types of tissue stem cells (e.g. skin, brain, or heart) from the same donor. Many living or recently deceased donors often cannot contribute these stem cells, so we need, in the future, a single biological source of each of the different types of stem cells (e.g., blood and heart) to change the entire field of regenerative medicine. The ultimate reason to fund embryonic stem cell and other pluripotent stem cell research is to create safe banks of predefined pluripotent cells. Protocols to differentiate these cells to the appropriate blood-forming stem cells could then be used to induce tolerance of other tissue stem cells from the same embryonic stem cell line. However, existing protocols to differentiation stem cells often lead to pluripotent cells (cells that generate multiple types of tissue), which pose a risk of generating normal tissue in the wrong location, abnormal tissue, or cancers called teratomas. To address these problems, we have concentrated our efforts to devise strategies to (a) make pluripotent cells develop into desired tissue-specific stem cells, and (b) to separate these desired cells from all other cells, including teratoma-causing cells. In the first funding period of this grant, we succeeded in raising antibodies that identify and eliminate teratoma-causing cells.
  • In the past year, we identified surface markers of cells that can only give rise to heart tissue. First we studied the genes that were activated in these cells, further confirming that they would likely give rise to heart tissue. Using antibodies against these surface markers, we purified heart stem cells to a higher concentration than has been achieved by other purification methods. We showed that these heart stem cells can be transplanted such that they integrate into the human heart, but not mouse heart, and participate in strong and correctly timed beating.
  • In the embryo, a group of early stem cells in the developing heart give rise to (a) heart cells; (b) cells lining the inner walls of blood vessels; and (c) muscle cells surrounding blood vessels. We identified cell surface markers that could be used to separate each of these subsets from each other and from their common stem cell parents. Finally, we determined that a specific chemical in the body, fibroblast growth factor, increased the growth of a group of pluripotent stem cells that give rise to more specific stem cells that produce either blood cells or the lining of blood vessels. This chemical also prevented blood-forming stem cells from developing into specific blood cells.
  • In the very early embryo, pluripotent cells separate into three distinct categories called ‘germ layers’: the endoderm, mesoderm, and ectoderm. Each of these germ layers later gives rise to certain organs. Our studies of the precursors of mesoderm (the layer that generates the heart, blood vessels, blood, etc.) led us by exclusion to develop techniques to direct ES cell differentiation towards endoderm (the layer that gives rise to liver, pancreas, intestinal lining, etc.). A graduate student before performed most of this work before he joined in our effort to find ways to make functional blood forming stem cells from ES cells. He had identified a group of proteins that we could use to sequentially direct embryonic stem cells to develop almost exclusively into endoderm, then subsets of digestive tract cells, and finally liver stem cells. These liver stem cells derived from embryonic stem cells integrated into mouse livers and showed signs of normal liver tissue function (e.g., secretion of albumin, a major protein in the blood). Using the guidelines of the protocols that generated these liver stem cells, we have now turned our attention back to our goal of generating from mesoderm the predecessors of blood-forming stem cells, and, ultimately, blood-forming stem cells.
  • In summary, we have continued to discover signals that cause pluripotent stem cells (which can generate many types of tissue) to become tissue-specific stem cells that exclusively develop into only heart, blood cells, blood vessel lining cells, cells that line certain sections of the digestive tract, or liver cells. This work has also involved determining the distinguishing molecules on the surface of various cells that allow them to be isolated and nearly purified. These results bring us closer to being able to purify a desired type of stem cell to be transplanted safely to generate only a single type of tissue.

A Novel Engineered Niche to Explore the Vasculogenic Potential of Embryonic Stem Cells

Funding Type: 
New Faculty I
Grant Number: 
RN1-00566
ICOC Funds Committed: 
$2 108 683
Disease Focus: 
Heart Disease
Stem Cell Use: 
Adult Stem Cell
Embryonic Stem Cell
oldStatus: 
Closed
Public Abstract: 
Cardiovascular diseases account for an estimated $330 billion in health care costs each year, afflict 61.8 million Americans, and will account for more than 1.5 million deaths in the U.S. this year alone. A number of these diseases are characterized by either insufficient blood vessel growth or damage to the existing vessels, resulting in inadequate nutrient and oxygen delivery to the tissues. The most common clinical example of this is a heart attack, or myocardial infarction, typically caused by blockage of a coronary artery. The resulting ischemia (reduced blood flow) induces irreversible damage to the heart, leaving behind a non-functional scar tissue. Efforts to restore blood flow to ischemic tissues have largely focused on the delivery of protein growth factors (called pro-angiogenic molecules) that stimulate new capillary growth. An alternative approach is to deliver an appropriate cell type that can either accelerate the recruitment of host vessels or can differentiate into a functional vasculature directly. While adult stem cells have shown promising potential with respect to the former, the potential of embryonic stem cells (ESCs) with respect to either of these two possibilities remains unclear. Therefore, this proposal seeks to: 1.) Utilize a novel, highly tunable, 3D engineered niche to investigate how changes in multiple instructive signals coordinately govern the differentiation of ESCs into capillary vessels; 2.) Exploit knowledge gained from basic studies using this model system to generate a purified population of ESC-derived endothelial progenitor cells (EPCs) and test their potential to repair ischemia in vivo. Specifically, in Aim 1, we propose to further develop and characterize our artificial engineered niche for fundamental studies on ESC fate decisions. Aim 2 will use this system to test two competing hypotheses, namely that: 1.) ESCs can facilitate capillary morphogenesis in an indirect manner, in much the same way as adult stem cells; or 2.) ESCs can be directed down an endothelial-specific lineage by manipulating one or more instructive signals. Finally, Aim 3 will utilize our engineered niche to generate a purified population of ESC-derived EPCs and then test their ability to enhance perfusion in an animal model. Successful completion of these proposed aims may transform the clinical use of stem cells for cardiovascular disease and other ischemic pathologies by enabling identification of those factors and conditions which promote vessel formation. The versatile artificial engineered niche developed here will also yield a new tool that could enormously benefit efforts to screen the combinatorial effects of promising therapeutic compounds. Completion of the planned studies will greatly facilitate the PI’s long-term goal of developing “instructive” biomaterials and strategies to direct tissue repair.
Statement of Benefit to California: 
Human embryonic stem cells (hESCs) are pluripotent stem cells that can theoretically give rise to every cell type in the human body. Their potential use for the treatment of human diseases has been heralded with great fanfare and even some controversy. However, their therapeutic potential has yet to be realized due to an incomplete fundamental understanding of the factors that govern their differentiation. This proposal describes studies intended to assess the ability of hESCs to develop into blood vessels; in particular, capillary networks that are responsible for the delivery of oxygen and essential nutrients to all tissues in the human body. This focus is motivated by the fact that cardiovascular disease accounts for an estimated $330 billion in health care costs each year, afflicts 61.8 million Americans, and will account for more than 1.5 million deaths in the United States this year alone. It is the number one killer in this country and in California. Since many cardiovascular diseases are characterized by either insufficient blood vessel growth or damage to the existing vessels, a therapy based on hESCs could have enormous benefit to the citizens of California, the United States, and the rest of the world. Therefore, this proposal has two primary goals. First, we seek to develop a novel technology to systematically investigate the influence of multiple instructive signals on the ability of hESCs to differentiate into capillary vessels. Second, we propose to exploit knowledge gained from the basic studies using this technology to generate a purified population of hESCs and test their potential to repair ischemia (lack of blood flow) in an animal model. Successfully achieving these goals will benefit the citizens of California in three significant ways. First, our efforts may help to transform the clinical use of stem cells, not only for cardiovascular disease but other diseases as well, by enabling identification of those factors and conditions which promote hESC differentiation. Second, the versatile technology developed here will yield a powerful new tool that could enormously benefit California’s biotechnology companies in their efforts to screen the combinatorial effects of promising therapeutic compounds. Third, we expect the proposed studies to directly benefit 8-10 researchers in training and indirectly trickle down to hundreds of undergraduate students [REDACTED] enrolled in courses taught by the PI. This final benefit may perhaps have the most significant long-term economic impact by training and inspiring future leaders to pursue research and development positions in California.

Transcriptional Regulation of Cardiac Pacemaker Cell Progenitors

Funding Type: 
New Faculty I
Grant Number: 
RN1-00562
ICOC Funds Committed: 
$3 149 806
Disease Focus: 
Heart Disease
Stem Cell Use: 
Embryonic Stem Cell
oldStatus: 
Active
Public Abstract: 
Congenital and acquired defects of cardiac pacemakers are leading causes of morbidity and mortality in our society. Dysfunctions of the SA node and the lower conduction cells lead to a variety of complex arrhythmias that typically necessitate anti-arrhythmic therapy and implantation of devices. These treatments have significant limitations in their efficacy and risk-benefit ratio. Thus, it would be ideal to generate cell-based therapeutic approaches towards treating arrhythmias. Experimental data has provided compelling evidence that pacemaker and conduction cells of the heart separate early in development from the working myocardium and retain a relatively undifferentiated state. Prior cell-based approaches in regenerating myocardial damage in the heart have met limited success in part due to implantation of a diverse population of cells. This generally results in poor engraftment and undesirable outcomes. There is now evidence for resident conduction progenitor cells in myocardium that orchestrate the process of cell recruitment into the conduction tissue. In the current proposal we aim to identify the molecular events that lead to differentiation and formation of cardiac pacemaker cells. We will utilize the information obtained from the above experiments to generate cell based methods to treat cardiac arrhythmias. We aim to genetically manipulate the human embryonic stem cells so we can identify a selected population that is destined to become pacemaker cells. By replacing the cells responsible for normal beating of the heart, we hope to provide natural therapies for human conduction system disease
Statement of Benefit to California: 
The ultimate of goal of our proposal is identify a reliable mechanism for implementing a cell-based approach for treating human arrhythmias. Sudden cardiac death related to cardiac arrhythmia is a leading cause of morbidity and mortality in our society. The people of California have voted to implement new innovative ways of treating human disease by using human stem cells, the current project is in line with such wishes to create new therapeutic modalities towards treating heart disease.
Progress Report: 
  • Cardiovascular disease is a major source of morbidity and mortality in our society. In this case, cardiac arrhythmias are leading cause of sudden cardiac death. Therefore, it is empirical to identify the source and mechanisms of cardiac arrhythmias. The long-term objectives of our laboratory is identify the key molecules that are involved in differentiation and formation of cardiac conduction system. We utilize mouse as a model system to identify the molecular pathways leading the formation of cardiac conduction cells.
  • In the past year we have identified some of regulatory pathways that allows for the proper formation of cardiac conduction tissue. We are using mice that have specific mutations in the cells of cardiac conduction system to identify these special pathways. One such molecule that orchestrates the differentiation of cardiac conduction cells is Nkx2-5. We have determined that loss of this transcription factor is of significant detriment to the health of cardiac conduction and is the underlying factor in common arrhythmias. Our ultimate goal is to utilize the information obtained by our studies in mice, and apply them towards therapeutic functions in humans. To this end, we are trying to develop a mechanism to reprogram cardiac stem cells to behave like conduction system cells. Ultimately, this approach would be used towards stem cell therapy for cardiac arrhythmias.
  • A leading cause of heart related morbidity and mortality is cardiac rhythm disturbances. In fact sudden cardiac death is primarily due to abnormalities of cardiac electrical conduction abnormalities. At present, the therapeutic approaches to treatment of cardiac arrhythmias are limited to cardiac device including pacemakers and defibrillators. These devices are expensive and carry additional risks to the patients during after surgical implantation. Our overall goal is to identify the key regulatory pathways that lead to differentiation and formation of various cells type of cardiac conduction cells.
  • Our laboratories focuses on the molecular pathways that guide the formation of distinct cell types in the human heart. The proper formation of these cell types from a unique cardiac progenitor is an important, yet complex biological question that our laboratory is aiming to answer. In this regard, in the past year we have identified a unique molecular pathway by which a unique population of cardiac progenitor cells are added to heart and also participate in the formation and patterning of the cardiac pacemaker cells. We are using mouse models to study the formation of cardiac stem cells and also the mechanisms by which they acquire distinct identities. To this end, our mutant mouse models display abnormal formation of the SA node which is the primary site of cardiac beating. By studying the mutant mice generated by genetic manipulation of stem cells, we aim to further advance our knowledge of different forms of cardiac stem cell formation. During the past year we have made significant progress in elucidating the ways by which cardiac progenitor cells contribute the pacemaker cell formation and putting forth new paradigms for cardiac pacemaker stem cell formation.
  • Heart disease is a major cause of morbidity and mortality in our society. Congestive heart failure and cardiac arrhythmias are the most common mechanism by which heart disease leads to sudden cardiac death. Genetic studies in the general population have determined that susceptibility to cardiac arrhythmia and congestive heart failure is due to mutations in certain genes that guide cardiac development. Specifically, mutations in certain molecules called transcription factors are the leading mechanisms by which genetic defects lead to congenital heart defects and cardiac arrhythmias. Our laboratory studies the mechanism by which transcription factors and signaling molecules guide cardiac development and lead to selective formation of different cardiac cells. Our laboratory has pioneered work that has lead to the discovery of mutations that lead to cardiac arrhythmia and heart failure. In the past year, we have made steady progress in characterization of some of the key factors that guide cardiac cell development. To this end, we have identified a molecule called R-spondin-3 (Rspo3) that is critical for cardiac cell growth and probably survival. We have determined that Rspo3 functions to keep cardiac cell proliferating and loss of Rspo3 leads to thin cardiac muscle and heart failure. The mutation of Rspo3 in mouse leads to not only heart failure, but also leads to arrhythmias and valvlular heart disease. Therefore, Rspo3 functions in multiple aspect cardiac development and plays an essential role in proliferation of resident cardiac stem cells. Since, Rspo3 is known to function in a specific cardiac pathway called Wnt pathway, our hypothesis is that Rspo3 is a needed growth factor that is guiding cardiac stem cells towards growth and proliferation. We have submitted a manuscript about our work with Rspo3.
  • Our laboratory has also identified a molecule called OSR1 which plays a critical role in cardiac septation and development of conduction system. Mice that lack Osr1 have defects in atrial septation and show evidence of cardiac arrhythmias. We are in the process of submitting a manuscript that describes our results with OSR1. In summary, the generous funding by CIRM has helped us identify important new molecules with novel mechanisms critical in cardiac development.
  • Heart disease is a major cause of morbidity and mortality in our society. Congestive heart failure and cardiac arrhythmias are the most common mechanism by which heart disease leads to sudden cardiac death. Genetic studies in the general population have determined that susceptibility to cardiac arrhythmia and congestive heart failure is due to mutations in certain genes that guide cardiac development. Specifically, mutations in certain molecules called transcription factors are the leading mechanisms by which genetic defects lead to congenital heart defects and cardiac arrhythmias. Our laboratory studies the mechanism by which transcription factors and signaling molecules guide cardiac development and lead to selective formation of different cardiac cells. Our laboratory has pioneered work that has lead to the discovery of mutations that lead to cardiac arrhythmia and heart failure. In the past year, we have made steady progress in characterization of some of the key factors that guide cardiac cell development. To this end, we have identified a molecule called R-spondin-3 (Rspo3) that is critical for cardiac cell growth and probably survival. We have determined that Rspo3 functions to keep cardiac cell proliferating and loss of Rspo3 leads to thin cardiac muscle and heart failure. The mutation of Rspo3 in mouse leads to not only heart failure, but also leads to arrhythmias and valvlular heart disease. Therefore, Rspo3 functions in multiple aspect cardiac development and plays an essential role in proliferation of resident cardiac stem cells. Since, Rspo3 is known to function in a specific cardiac pathway called Wnt pathway, our hypothesis is that Rspo3 is a needed growth factor that is guiding cardiac stem cells towards growth and proliferation. We have submitted a manuscript about our work with Rspo3.
  • Our laboratory has also identified a molecule called OSR1 which plays a critical role in cardiac septation and development of conduction system. Mice that lack Osr1 have defects in atrial septation and show evidence of cardiac arrhythmias. We are in the process of submitting a manuscript that describes our results with OSR1. In summary, the generous funding by CIRM has helped us identify important new molecules with novel mechanisms critical in cardiac development.

Induction of cardiogenesis in pluripotent cells via chromatin remodeling factors

Funding Type: 
New Faculty II
Grant Number: 
RN2-00903
ICOC Funds Committed: 
$2 847 600
Disease Focus: 
Heart Disease
Stem Cell Use: 
Embryonic Stem Cell
iPS Cell
oldStatus: 
Closed
Public Abstract: 
Heart disease is one of the biggest killers in the civilized world, and as populations age, this trend will increase dramatically. Currently the only way to treat failing hearts is with expensive and relatively ineffective drugs, or by heart transplantation. Ideally, we would like to be able to regenerate sick or dead heart tissue. The best strategy would be to make new heart cells that match the patients' cells (to avoid rejection), and inject them into diseased heart so that they could regenerate the sick heart.Unfortunately, current strategies that are planned to do so are ineffectual. We wish to attempt to generate heart cells from human embryonic stem cells, or skin-derived "induced pluripotent cells" by "reprogramming" the stem cells into heart cells. This would be accomplished by turning on heart genes that normally are off in stem cells and seeing if this turns stem cells into heart cells. If this approach is successful, these newly generated stem cells could be used for regenerative therapies in the future.
Statement of Benefit to California: 
Heart disease is the leading killer of adults in the Western world. Hundreds of thousands of people in the US die of heart failure of sudden cardiac death each year. Largely, this is because inadequate therapies exist for the repair or treatment of the diseased heart. Our goal is to develop a means to efficiently convert pluripotent stem cells, including induced pluripotent cells (iPS cells) into new heart cells that could be used therapeutically to help regenerate healthy heart tissue. The results of our studies will help develop new technology that is likely to contribute to the California biotechnology industry. Our studies will develop technologies that can be used by biotechnology companies and researchers who wish to develop regenerative medicine therapies in a clinical setting. We are working closely with California companies to develop new microscopes, assay devices, and analytical software that could be the basis for new product lines or new businesses. If therapies do come to fruition, we anticipate that California medical centers will be leading the way. The most important contribution of this study will be to improve the health of Californians. Heart disease is a major cause of mortality and morbidity, resulting in billions of dollars in health care costs and lost days at work. Our goal is to contribute research that would ultimately improve the quality of life and increase productivity for millions of people who suffer from heart disease.
Progress Report: 
  • We hypothesized that human embryonic stem cells (hESCs) or induced pluripotent stem cells (iPS cells, which are derived from skin or other adult cells) can be efficiently reprogrammed to become heart cells using a combination of factors that includes proteins that unwind DNA. To test this hypothesis, we proposed three specific aims. For each we have achieved significant progress. In progress toward our first aim, we have been able to enhance cardiac differentiation of mouse iPS cells by 20%, and have devised strategies to increase this success rate. Our second aim was directed at understanding how important the chromatin remodeling factor, Baf60c, was in the induction of heart cells from pluripotent cells. We have made significant progress in this regard, mostly in developing the complex genetic tools required to investigate this important question. The third aim was to understand how Baf60c and its collaborating factors work to enhance heart cell formation. Again, we have had considerable success in early experiments that indicate that we will be able to address these questions fully in the remaining years of the granting period. Overall, our first year of funding has allowed us to move rapidly forward in understanding how to propel a stem cell toward becoming a heart cell; these results will be important to understand how heart cells are made in the body, and how their genesis can be harnessed using the power of stem cells.
  • We have been studying ways to understand how heart cells form from stem cells, and how we could help make the process more efficient, to generate new heart cells for patients with damaged hearts due to heart attacks. We have focused on the finding that cellular machines that unwind DNA from chromosomes, so-called chromatin remodeling factors, are important for turning on heart genes. To date we have been generating the important biological tools required for these studies. These include stem cells in which some of these chromatin genes have been inactivated, as well as DNA constructions that will be inserted into embryonic stem cells to attempt to induce them to become heart cells. In parallel we have been working towards using these factors to transform other types of cells, such as skin cells, into cardiomyocytes; in collaboration with our colleagues we have made significant progress towards this goal, and are now investigating the importance of the chromatin remodeling complexes in this process. Our progress has been excellent, and we are confident that we are making great strides towards regenerative medicine in the context of heart disease.
  • We have been studying ways to understand how heart cells form from stem cells, and how we could help make the process more efficient, to generate new heart cells for patients with damaged hearts due to heart attacks. We have focused on the finding that cellular machines that unwind DNA from chromosomes, so-called chromatin remodeling factors, are important for turning on heart genes. To date we have been generating the important biological tools required for these studies. These include stem cells in which some of these chromatin genes have been inactivated, as well as DNA constructions that will be inserted into embryonic stem cells to attempt to induce them to become heart cells. In parallel we have been working towards using these factors to transform other types of cells, such as skin cells, into cardiomyocytes; in collaboration with our colleagues we have made significant progress towards this goal, and are now investigating the importance of the chromatin remodeling complexes in this process. Our progress has been excellent, and we are confident that we are making great strides towards regenerative medicine in the context of heart disease.
  • In the last year, we have made significant progress on this project, which aims to understand how heart cells can be produced from pluripotent cells. We have been able to understand the gene program that is controlled by a so-called chromatin remodeling protein, a protein that unwinds DNA to allow genes to be turned on. This protein, called Baf60c, turns on many of the genes that give a heart cell its basic functions, like beating. We have also created stem cell -based tools that will allow us in the final year of this project to identify the partner proteins that allow Baf60c to function, and where in our genome Baf60c turns genes on.
  • During the tenure of this award, we have made some exciting discoveries about how genes are regulated during the process of heart cell formation from embryonic stem cells. In particular, we focused our efforts on a group of proteins that regulate other genes using a process called chromatin remodeling. We discovered that one such chromatin remodeling protein is required for genes that are specific to the heart to be turned on in heart cells. We also discovered new proteins that are also important for the formation of the heart. In studying these chromatin remodeling proteins in an embryonic stem cell system, we identified how these proteins turn on the "right" set of genes in the earliest stages of commitment of stem cells to heart cell progenitors. Finally, we identified the nature of the group of proteins that work together as part of chromatin remodeling "complexes", which for the first time tells us how these proteins assemble together to regulate heart genes. These results have paved the way for studies aimed at creating new heart cells, and have opened up some exciting new possibilities to improve this process.

Center of Excellence for Stem Cell Genomics

Funding Type: 
Genomics Centers of Excellence Awards (R)
Grant Number: 
GC1R-06673-A
ICOC Funds Committed: 
$40 000 000
Disease Focus: 
Brain Cancer
Cancer
Developmental Disorders
Heart Disease
Cancer
Genetic Disorder
Stem Cell Use: 
iPS Cell
Embryonic Stem Cell
Adult Stem Cell
Cancer Stem Cell
Cell Line Generation: 
iPS Cell
Public Abstract: 
The Center of Excellence in Stem Cell Genomics will bring together investigators from seven major California research institutions to bridge two fields – genomics and pluripotent stem cell research. The projects will combine the strengths of the center team members, each of whom is a leader in one or both fields. The program directors have significant prior experience managing large-scale federally-funded genomics research programs, and have published many high impact papers on human stem cell genomics. The lead investigators for the center-initiated projects are expert in genomics, hESC and iPSC derivation and differentiation, and bioinformatics. They will be joined by leaders in stem cell biology, cancer, epigenetics and computational systems analysis. Projects 1-3 will use multi-level genomics approaches to study stem cell derivation and differentiation in heart, tumors and the nervous system, with implications for understanding disease processes in cancer, diabetes, and cardiac and mental health. Project 4 will develop novel tools for computational systems and network analysis of stem cell genome function. A state-of-the-art data management program is also proposed. This research program will lead the way toward development of the safe use of stem cells in regenerative medicine. Finally, Center resources will be made available to researchers throughout the State of California through a peer-reviewed collaborative research program.
Statement of Benefit to California: 
Our Center of Excellence for Stem Cell Genomics will help California maintain its position at the cutting edge of Stem Cell research and greatly benefit California in many ways. First, diseases such as cardiovascular disease, cancer, neurological diseases, etc., pose a great financial burden to the State. Using advanced genomic technologies we will learn how stem cells change with growth and differentiation in culture and can best be handled for their safe use for therapy in humans. Second, through the collaborative research program, the center will provide genomics services to investigators throughout the State who are studying stem cells with a goal of understanding and treating specific diseases, thereby advancing treatments. Third, it will employ a large number of “high tech” individuals, thereby bringing high quality jobs to the state. Fourth, since many investigators in this center have experience in founding successful biotech companies it is likely to “spin off” new companies in this rapidly growing high tech field. Fifth, we believe that the iPS and information resources generated by this project will have significant value to science and industry and be valuable for the development of new therapies. Overall, the center activities will create a game-changing network effect for the state, propelling technology development, biological discovery and disease treatment in the field.

Improving Existing Drugs for Long QT Syndrome type 3 (LQT3) by hiPSC Disease-in-Dish Model

Funding Type: 
Early Translational IV
Grant Number: 
TR4-06857
ICOC Funds Committed: 
$6 361 618
Disease Focus: 
Heart Disease
Stem Cell Use: 
iPS Cell
Cell Line Generation: 
iPS Cell
oldStatus: 
Active
Public Abstract: 
This project uses patient hiPSC-derived cardiomyocytes to develop a safe and effective drug to treat a serious heart health condition. This research and product development will provide a novel method for a human genetic heart disorder characterized by long delay (long Q-T interval) between heart beats caused by mutations in the Na+ channel α subunit. Certain patients are genetically predisposed to a potentially fatal arrhythmogenic response to existing drugs to treat LQT3 since the drugs have off-target effects on other important ion channels in cardiomyocytes. We will use patient-derived hiPSC-cardiomyocytes to develop a safer drug (development candidate, DC) that will retain efficacy against the "leaky" Na+-channel yet minimize off-target effects in particular against the K+ hERG channel that can be responsible for the existing drug’s pro-arrhythmic effect. Since this problem is thought to occur severely in patients with the common KCHN2 variant, K897T (~33% of the white population), removing the off-target liability addresses a serious unmet clinical need. Futher, since we propose to modify an existing drug (i.e., do drug rescue), the path from patient-specific hiPSCs to clinic might be easier than for a completely new chemical entity. Lastly, an appealing aspect is that the hiPSCs were derived from a child to test his therapy, & we aim to produce a better drug for his treatment. Our goal is to complete development of the DC and initiate IND-enabling in vivo studies.
Statement of Benefit to California: 
In the US, an estimated 850,000 adults are hospitalized for arrhythmias each year, making arrhythmias one of the top five causes of healthcare expenditures in the US with a direct cost of more than $40 billion annually for diagnosis, treatment & rehabilitation. The State of California has approximately 12% of the US population which translates to 102,000 individuals hospitalized every year for arrhythmias. Another 30,000 Californians die of sudden arrhythmic death syndrome every year. Arrhythmias are very common in older adults and because the population of California is aging, research to address this issue is important for human health and the State economy. Most serious arrhythmias affect people older than 60. This is because older adults are more likely to have heart disease & other health problems that can lead to arrhythmias. Older adults also tend to be more sensitive to the side effects of medicines, some of which can cause arrhythmias. Some medicines used to treat arrhythmias can even cause arrhythmias as a side effect. In the US, atrial fibrillation (a common type of arrhythmia that can cause problems) affects millions of people & the number is rising. Accordingly, the same problem is present in California. Thus, successful completion of this work will not only provide citizens of California much needed advances in cardiovascular health technology & improvement in health care but an improved heart drug. This will provide high paying jobs & significant tax revenue.

Tissue Collection for Accelerating iPSC Research in Cardiovascular Diseases

Funding Type: 
Tissue Collection for Disease Modeling
Grant Number: 
IT1-06596
Investigator: 
ICOC Funds Committed: 
$1 435 371
Disease Focus: 
Heart Disease
oldStatus: 
Active
Public Abstract: 
Heart failure is a very common and chronic condition defined by an inability of the heart to pump blood effectively. Over half of cases of heart failure are caused by a condition called dilated cardiomyopathy, which involves dilation of the heart cavity and weakening of the muscle. Importantly, many cases of this disease do not have a known cause and are called “idiopathic” (i.e., physicians do not know why). Over the past 2 decades, doctors and scientists started realizing the disease can cluster in families, leading them to think there is a genetic cause to the disease. This resulted in discovering multiple genes that cause this disease. Nonetheless, the majority of cases of dilated hearts that cluster in families do not have a known genetic cause. Now scientists can turn blood and skin cells into heart cells by genetically manipulating them and creating engineered stem cells called “induced pluripotent stem cells” or iPSCs. This approach enables the scientists to study what chemical or genetic changes are happening to cause the problem. Also because these cells behave similar to the cells in the heart, scientists can now test new medicines on these cells first before trying them in patients. Here we aim to collect tissue from 800 patients without a known cause for their dilated hearts (and 200 control individuals) to help accelerate our understanding of this debilitating disease and hopefully offer new and better treatments.
Statement of Benefit to California: 
Heart failure is a significant health burden in California with rising hospitalization and death rates in the state. We have a very limited understanding of the disease and so far the existing treatments only slow down the disease and the changes that happen rather than target the root cause. By studying a subgroup of the dilated cardiomyopathy patients who have no identified cause, we can work on identifying genetic causes of the disease, some of the biology happening inside the heart cell, and provide new treatments that can prevent the disease from happening or progressing. Improving the outcome of this debilitating disease and providing new treatments will go a long way to helping a large group of Californians lead healthier and longer lives. There are estimates that the US economy loses $10 billion (not counting medical costs), because heart failure patients are unable to work. Hence new knowledge and developments gained from this research can go a long way to ameliorating that cost. Finally, heart failure is the most common chronic disease patients in California are hospitalized for. This research targets over half of those admissions. If this research is able to cut the hospitalization rate even by 1%, this would translate to millions of dollars in savings to the state. Continuing to invest in innovation will make our state a hotbed for the biotechnology industry, which in turn advances the state’s economic and educational status.

Human Embryonic Stem Cell-Derived Cardiomyocytes for Patients with End Stage Heart Failure

Funding Type: 
Disease Team Therapy Development - Research
Grant Number: 
DR2A-05394
ICOC Funds Committed: 
$19 999 899
Disease Focus: 
Heart Disease
Stem Cell Use: 
Embryonic Stem Cell
oldStatus: 
Active
Public Abstract: 
Patients with end-stage heart failure have a 2-year survival rate of only 50% with conventional medical therapy. This dismal survival rate is actually significantly worse than patients with AIDS, liver cirrhosis, stroke, and other comparable debilitating diseases. Currently available therapies for end stage heart failure include drug and device therapies, as well as heart transplantation. While drug and device therapies have proven effective at reducing symptoms, hospitalizations and deaths due to heart failure, new approaches are clearly required to improve this low survival rate. Organ transplantation is highly effective at increasing patient survival, but is severely limited in its potential for broad-based application by the very low number of hearts that are available for transplantation each year. Stem cell therapy may be a promising strategy for improving heart failure patient outcomes by transplanting cells rather than a whole heart. Several studies have convincingly shown that human embryonic stem cells can be differentiated into heart muscle cells (cardiomyocytes) and that these cells can be used to improve cardiac function following a heart attack. The key objective of this CIRM Disease Team Therapy proposal is to perform the series of activities necessary to obtain FDA approval to initiate clinical testing of human embryonic stem cell-derived cardiomyocytes in end stage heart failure patients.
Statement of Benefit to California: 
Coronary artery disease (CAD) is the number one cause of mortality and morbidity in the US. The American Heart Association has estimated that 5.7 million Americans currently suffer from heart failure, and that another 670,000 patients develop this disease annually. Cardiovascular disease has been estimated to result in an estimated $286 billion in direct and indirect costs in the US annually (NHLBI, 2010). As the most populous state in the nation, California bears a substantial fraction of the social and economic costs of this devastating disease. In recent years, stem cell therapy has emerged as a promising candidate for treating ischemic heart disease. Research by our group and others has demonstrated that human embryonic stem cells (hESCs) can be differentiated to cardiomyocytes using robust, scalable, and cGMP-compliant manufacturing processes, and that hESC-derived cardiomyocytes (hESC-CMs) can improve cardiac function in relevant preclinical animal models. In this proposal, we seek to perform the series of manufacturing, product characterization, nonclinical testing, clinical protocol development, and regulatory activities necessary to enable filing of an IND for hESC-CMs within four years. These IND development activities will be in support of a Phase 1 clinical trial to test hESC-CMs in heart failure patients for the first time. If successful, this program will both pave the way for a promising new therapy to treat Californians with heart failure numbering in the hundreds of thousands, and will further enhance California’s continuing prominence as a leader in the promising field of stem cell research and therapeutics.
Progress Report: 
  • Patients with end-stage heart failure (ESHF), which can result from heart attacks, have a 2-year survival rate of 50% with conventional medical therapy. Unlike cells of other organs, the billions of cardiomyocytes lost due to damage or disease do not regenerate. Recently, implantable mechanical pumps that take over the function of the failing left ventricle (left ventricular assist devices; LVADs) have been used to prolong the lives of heart failure patients. However, these devices carry an increased risk of stroke. The only current bona fide cure for ESHF is heart transplantation, but the shortage of donor organs and the risks associated with life-long use of powerful immunosuppressive drugs limit the number of patients that can be helped.
  • Human embryonic stem cells (hESCs) have the unique properties of being able to grow without limit and to be converted into all the cell types of the body, including cardiomyocytes. Our project seeks to find ways to treat patients by replacing their lost cardiomyocytes with healthy ones derived from hESC. The ultimate goal of this 4 year project is to evaluate the feasibility, safety, and efficacy of this approach in both small and large animal models of heart disease and to use this data to initiate a clinical trial to test the therapy in patients.
  • In our first year, we developed methods for producing essentially unlimited quantities of cardiomyocytes from hESCs using a process that is compatible both with clinical needs and large-scale industrial cell production. We have also developed models of heart disease in both rats and pigs, and have begun transplanting the stem cell-derived cardiomyocytes into the rat model. We have demonstrated that stem cell-derived cardiomyocytes can engraft in this animal model and we are testing their effects on the pumping function of the heart, the growth of replacement blood vessels lost during a heart attack, and the size of the scar that typically forms after injury. In the next several years, we will continue to evaluate the safety and function of these cells and will start to transplant in our large animal model of heart disease, which will enable us to test these cells in a heart with very similar characteristics to humans, delivered in a minimally invasive way that would be ideal for clinical use.

Allogeneic Cardiac-Derived Stem Cells for Patients Following a Myocardial Infarction

Funding Type: 
Disease Team Therapy Development - Research
Grant Number: 
DR2A-05735
ICOC Funds Committed: 
$19 782 136
Disease Focus: 
Heart Disease
Stem Cell Use: 
Adult Stem Cell
oldStatus: 
Active
Public Abstract: 
The proposed research will demonstrate both safety and efficacy of a heart-derived stem cell product in patients who have experienced a heart attack either recently or in the past by conducting a mid-stage clinical trial. A prior early-stage trial showed that the product can repair damaged portions of the heart after a heart attack in ways that no commercial therapy currently can. Damaged areas turn irreversibly into scar tissue after the initial event, which can predispose a person to future events and lead to an ongoing worsening of general and heart health. Data from the early-stage trial suggest that treatment with the heart-derived cell product under development can turn scar tissue back into healthy heart muscle. The planned mid-stage trial will hopefully confirm that finding in a larger patient group and provide additional data to support the safety profile of the product. The product is manufactured using heart tissue obtained from a healthy donor and can be used in most other individuals. Its effect is thought to be long-lasting (months-years) although it is expected to be cleared from the body relatively quickly (weeks-months). Treatment is administered during a single brief procedure, requiring a local anesthetic and insertion of a tube (or catheter) into the heart. The overriding goal for the product is to prevent patients who have had a heart attack from deteriorating over time and developing heart failure, a condition which is defined by the heart’s inability to pump blood efficiently and one which affects millions of Americans. Successful completion of the proposed mid-stage trial would lead next to a final, confirmatory trial and then to the application process by which permission to market the product is obtained from the Food and Drug Administration. The end result could be an affordable stem cell therapy effective as part of a treatment regimen after a heart attack.
Statement of Benefit to California: 
The manufacturer of the heart-derived stem cell product under development is a California-based small company who currently employs 7 California residents. Five new local jobs will be created to support the proposed project. Three medical centers located in California will participate in the proposed mid-stage clinical trial. The trial will hopefully bring notoriety to both the company and the medical centers involved while at the same time provide a novel therapeutic option for the many citizens of California afflicted with heart disease. Recent statistics place California among the 50% of states with the highest death rates for heart disease. Therefore, a successfully developed cell product could have a meaningful impact on the home population. Furthermore, as manufacturing needs grow to accommodate the demands of early commercialization, the company anticipates generating 100+ new biotech jobs.
Progress Report: 
  • This project aims to demonstrate both safety and efficacy of a heart-derived cell product in patients who have experienced a heart attack either recently or in the past by conducting a mid-stage (Phase II) clinical trial. The cell product is manufactured using heart tissue obtained from a healthy donor and can be used in most other individuals. Its effect is thought to be long-lasting (months-years) although it is expected to be cleared from the body relatively quickly (weeks-months). Treatment is administered during a single brief procedure, requiring a local anesthetic and insertion of a tube (or catheter) into the heart. The overriding goal for the product is to prevent patients who have had a heart attack from deteriorating over time and developing heart failure, a condition which is defined by the heart’s inability to pump blood efficiently and one which affects millions of Americans. At the outset of the project, a Phase I trial was underway. By the close of the current reporting period, the Phase 1 trial had reached its main safety endpoint, and the Phase II trial was approved to proceed. Fourteen patients were treated with the heart-derived cell product as part of Phase I. The safety endpoint for the trial was pre-defined and took into consideration the following: inflammation in the heart accompanied by an immune response, death due to abnormal heart rhythms, sudden death, repeat heart attack, treatment for symptoms of heart failure, need for a heart assist device, and need for a heart transplant. Both an independent Data and Safety Monitoring Board (DSMB) and CIRM agreed that Phase I met its safety endpoint and that Phase II was approved to proceed. The Phase I participants continue to be monitored for safety and efficacy. Meanwhile, the manufacturing processes established to create cell products for use in Phase I, were employed to create cell products in anticipation of Phase II. A supply of products was readied for use in Phase II. Also in anticipation of Phase II, a number of clinical sites were readied for participation. Manufacturing data and trial status updates were also provided to the Food and Drug Administration (FDA).

The CIRM Human Pluripotent Stem Cell Biorepository – A Resource for Safe Storage and Distribution of High Quality iPSCs

Funding Type: 
hPSC Repository
Grant Number: 
IR1-06600
ICOC Funds Committed: 
$9 999 834
Disease Focus: 
Developmental Disorders
Heart Disease
Infectious Disease
Alzheimer's Disease
Neurological Disorders
Autism
Respiratory Disorders
Vision Loss
Stem Cell Use: 
iPS Cell
Cell Line Generation: 
iPS Cell
oldStatus: 
Active
Public Abstract: 
Critical to the long term success of the CIRM iPSC Initiative of generating and ensuring the availability of high quality disease-specific human IPSC lines is the establishment and successful operation of a biorepository with proven methods for quality control, safe storage and capabilities for worldwide distribution of high quality, highly-characterized iPSCs. Specifically the biorepository will be responsible for receipt, expansion, quality characterization, safe storage and distribution of human pluripotent stem cells generated by the CIRM stem cell initiative. This biobanking resource will ensure the availability of the highest quality hiPSC resources for researchers to use in disease modeling, target discovery and drug discovery and development for prevalent, genetically complex diseases.
Statement of Benefit to California: 
The generation of induced pluripotent stem cells (iPSCs) from patients and subsequently, the ability to differentiate these iPSCs into disease-relevant cell types holds great promise in facilitating the “disease-in-a-dish” approach for studying our understanding of the pathological mechanisms of human disease. iPSCs have already proven to be a useful model for several monogenic diseases such as Parkinson’s, Fragile X Syndrome, Schizophrenia, Spinal Muscular Atrophy, and inherited metabolic diseases such as 1-antitrypsin deficiency, familial hypercholesterolemia, and glycogen storage disease. In addition, the differentiated cells obtained from iPSCs represent a renewable, disease-relevant cell model for high-throughput drug screening and toxicology/safety assessment which will ultimately lead to the successful development of new therapeutic agents. iPSCs also hold great hope for advancing the use of live cells as therapies for correcting the physiological manifestations caused by disease or injury.

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