Myelomeningocele – also known as spina bifida – is a devastating and costly defect that causes lifelong paralysis as well as bowel and bladder incontinence in newborns. It is one of the most common birth defects worldwide, with four children in the United States born with spina bifida every day. Spina bifida affects the physical, educational, social, and psychological development of these children. Most patients require multiple surgeries and hospitalizations throughout their lives. Physicians are now able to diagnose this disease during pregnancy, and new fetal surgical techniques allow surgeons to safely operate on these children in the womb. This unique fetal surgery was studied in the award winning Management of Myelomeningocele Study (MOMS). The MOMS trial showed – for the first time ever – that the paralysis associated with spina bifida could be improved. Children treated in the womb were more likely to walk independently than those who were repaired after birth. However, the improvements seen were not perfect and the majority of children treated with fetal surgery still had some level of paralysis or lower extremity weakness.
Our research has built upon the success of the MOMS trial to address the residual deficits seen in children even after treatment with fetal surgery. We have developed a placental stem cell based therapy that can be applied at the time of fetal repair, in order to reverse spinal cord damage. After six years of laboratory research investigating different stem cell types and the best way to deliver a stem cell based treatment in the womb, we have discovered a placental stem cell therapy that cures spina bifida in the animal model. Animals treated with these cells can make a full recovery and are able to walk normally without any evidence of lower extremity paralysis. These amazing results require additional testing and FDA approval before the therapy can be used in humans. With this proposal, we will optimize this stem cell product, validate its effectiveness, determine the optimal dose, and confirm its preliminary safety in order to translate this new treatment to clinical trials. Stem cell therapy for spina bifida could cure this devastating disease, alleviating a massive burden on children, families, and society.
Spina bifida is one of the most common, costly, and disabling birth defects. Within the United States, four children per day are born with this devastating disease. In California, the 5-year statewide incidence of spina bifida was 6.8 cases per 10,000 live births between 1999 and 2003, significantly higher than the Healthy People 2010 target of 3 per 10,000 births. Additionally, spina bifida disproportionately affects Americans of Hispanic and Latino descent, who make up 37.6% of California’s population. Given the disproportionately high incidence of children born with spina bifida in California, and the lifelong disability these children live with, spina bifida is a substantial economic burden to the state. The estimated average total lifetime cost to California is approximately $532,000 for each child born with spina bifida. However, for many children, the cost may be several million dollars due to repeat surgical procedures, frequent hospitalizations, and the need for ongoing physical and cognitive rehabilitation. In addition to the direct medical costs associated with spina bifida, the indirect costs include: pain and suffering, cost of specialized childcare, and the lost earning potential of unpaid caregivers, which compound the impact the disease has on California’s economy.
There is currently no cure for spina bifida, and interventions that mitigate the negative consequences of the disease (lower body paralysis, bowel and bladder incontinence) are urgently needed. For the first time, hope for an improved treatment option was provided by the award winning Management of Myelomeningocele Study (MOMS). The MOMS trial was a multicenter randomized controlled trial demonstrating that the paralysis associated with spina bifida might be improved by surgical repair of the defect before birth. This promise of fetal intervention for spina bifida was based on the hypothesis that early in utero treatment would have the potential to fix the defect before permanent spinal cord damage occurred. While the MOMS trial did demonstrate an improvement in the lower extremity paralysis of those patients undergoing in utero repair compared to postnatal repair, these improvements were not universal for all children. This proposal presents an innovative placental stem cell-based therapy to augment fetal repair and further improve and possibly cure the devastating and costly neurologic deficits of spina bifida. A cure for spina bifida would relieve California families and society of the tremendous emotional and economic cost burden of this debilitating disease, and would be life changing for future children afflicted with spina bifida.
Microglia are a type of immune cell within the brain that profoundly influence the development and progression of many neurological disorders. Microglia also inherently migrate toward areas of brain injury, making them excellent candidates for use in cell transplantation therapies. Despite the widely accepted importance of microglia in neurological disease, methods to produce microglia from stem cells have yet to be reported. Our team has recently developed one of the first protocols to generate microglia from human pluripotent stem cells. We have used several approaches to confirm that the resulting cells are microglia including examination of gene expression and testing of key microglial functions. However, our current protocol uses cell culture supplements that preclude the use of these cells for any future clinical applications in people. The major goal of this proposal is to resolve this problem. We will generate pluripotent human stem cells that have special "reporter" genes that make the cells glow as they become microglia, allowing us to readily monitor and quantify the generation of these important cells. Using these reporter lines we can then streamline the differentiation process and develop improved protocols that could be translated toward eventual clinical use. As a proof-of-principle experiment we will then use the resulting human microglia to study some important questions about the genetic causes and potential treatment of Alzheimer’s disease.
Recent estimates suggest that nearly 2 million Californian adults are currently living with a neurological disorder. While the causes of neurological disease vary widely from Alzheimer’s disease to Stroke to Traumatic Brain Injury, a type of brain cell called microglia has been strongly implicated in all of these disorders. Microglia are often considered the immune cell of the brain, but they play many additional roles in the development and function of the nervous system. In neurological disease, Microglia appear to be involved in a response to injury but they can also secrete factors that exacerbate neurological impairment. Unfortunately, it has been difficult to study human microglia and their role in these diseases because of challenges in producing these cells. Our group recently developed an approach to ‘differentiate’ microglia from human pluripotent stem cells. This enables researchers to now study the role of different genes in human microglial function and disease. Yet our current approach dose not allow these cells to be used for potential clinical testing in patients. Our proposal therefore aims to develop new tools and technology that will allow us to produce clinically-relevant human microglia. These cells will then be used to study the role of a specific microglial gene in Alzheimer’s disease, and may ultimately be useful for developing treatments for the many Californians suffering from neurological disease.
One critical bottleneck in the translation of regenerative medicine into the clinic is the efficient delivery and engraftment of transplanted cells. While direct injection is the least invasive method for cell delivery, it commonly results in the survival of only 5-20% of cells. Studies suggest that delivery within a carrier gel may enhance cell viability, but most of the gels used previously were naturally derived materials that have complex and unknown compositions. In our previous CIRM-funded work, we discovered that pre-encapsulating cells in very weak hydrogels offers the best protection during injection; however, those gels may be too compliant to support long-term cell survival. To address these limitations, we propose the design of a fully defined, customizable, and injectable material that initially forms a weak gel that then stiffens post-injection. We focus our studies on the delivery of human induced pluripotent stem cell-derived neural progenitors for the treatment of spinal cord injury (SCI). There are ~12,000 new SCI patients in the US each year, primarily young adults. SCI commonly results in paralysis, and the estimated lifetime cost for a patient can rise above $4 million dollars. In preclinical models of SCI, stem cell therapies have resulted in partial regeneration; however, reproducible delivery and engraftment of sufficient cells remain difficult and unmet challenges. This award potentially develops transformational regenerative therapies for SCI.
The annual incidence of spinal cord injuries (SCI) in the United States is estimated at 12,000 new cases per year, with motor vehicle crashes accounting for up to a third of these cases. SCI has devastating impacts not only on the quality of life for the victims and their families, but also on their economic security – the estimated lifetime cost of an SCI patient can rise to over $4 million dollars depending on the severity and age at which the injury was sustained, not including the loss of wages and productivity. Although the most prevalent types of SCIs are those sustained at either the cervical or thoracic vertebrae, there are currently no definitive therapies approved for the chronic management of these SCI. Stem cell-based therapies have recently been shown to be mildly successful in several clinical and pre-clinical trials in various injuries and diseases, and a number of trials are ongoing for applications in SCI. In our proposal, we seek to advance the stem cell-based approach to the treatments of SCI. The potential benefit of this proposal to the state of California and its citizens include 1) the provision of a better medical prognosis for patients with spinal cord injuries, 2) the improved quality of life for SCI patients and their families, 3) the reduction of the burden of health care costs, 4) the creation and maintenance of jobs in the stem cell technology field, and 5) preserving California’s prominence in the field of stem cell research.
Most children who go to the clinic with brain disorders have symptoms combining autism, cerebral palsy and epilepsy, suggesting underlying and shared mechanisms of brain dysfunction in these conditions. Such disorders affect 4-6% of the population with life-long disease, and account for about 10% of health care expenditures in the US. Genetic studies have pointed to frequent low-penetrant or low-frequency genetic alterations, but there is no clear way to use this information to make gene-specific diagnosis, to predict short- or long-term prognosis or to develop disease-specific therapy. We propose to recruit about 500 patients with these disorders mostly from our Children’s Hospital, through a dedicated on-site collaborative approach. Extracting from existing medical records, taking advantage of years of experience in recruitment and stem cell generation, and already existing or planned whole exome or genome sequencing on most patients, we propose a safe, anonymous database linked to meaningful biological, medical, radiographic and genetic data. Because team members will be at the hospital, we can adjust future disease-specific recruitment goals depending upon scientific priorities, and re-contact patients if necessary. The clinical data, coupled with the proposed hiPSC lines, represents a platform for cell-based disease investigation and therapeutic discovery, with benefits to the children of California.
This project can benefit Californians both in financial and non-financial terms. NeuroDevelopmental Disabilities (NDDs) affect 4-6% of Californians, create a huge disease burden estimated to account for 10% of California health care costs, and have no definitive treatments. Because we cannot study brain tissue directly, it is extraordinarily difficult to arrive at a specific diagnosis for affected children, so doctors are left ordering costly and low-yield tests, which limit prognostic information, counseling, prevention strategies, quality of life, and impede initiation of potentially beneficial therapies. Easily obtainable skin cells from Californians will be the basis of this project, so the study results will have maximal relevance to our own population. By combining “disease in a dish” platforms with cutting edge genomics, we can improve diagnosis and treatments for Californians and their families suffering from neurodevelopmental disorders.
Additionally, this project, more than others, will help Californians financially because: 1] The ongoing evaluations of this group of patients utilizes medical diagnostics and genetic sequencing tools developed and manufactured in California, increasing our state revenues. 2] The strategy to develop “disease in a dish” projects centered on Neurodevelopmental Disabilities supports opportunities for ongoing efforts of California-based pharmaceutical and life sciences companies to leverage these discoveries for future therapies.
- Childhood Neurodevelopmental Disabilities (NDDs) affect approximately 12% of children in the US, and account for >5% of total healthcare costs. The ability to use induced pluripotent stem cells (iPSCs) to incorporate characteristics of patient cells into models that predict patient disease characteristics and clinical outcomes can have a major impact on care for the children with these conditions. We have proposed to ascertain pediatric patient samples which represent a range of NDDs including Autism Spectrum Disorders (ASD), Intellectual Disability (ID), Cerebral Palsy (CP) and Epilepsy for iPSC banking. These disorders were chosen because they have high heritability rates but remain genetically complex, and therefore, will greatly benefit from further in-depth study using iPSCs
- To date we have enrolled 128 patients (72 affected patients, 56 healthy control patients) representing a range of racial and ethnic backgrounds (39% White, 2% Black, 2% Asian, 57% Arabic/Middle Eastern) and both genders (52% Male, 48% Female). The patients in the affected patient group carry a primary diagnosis of one of the NDD disease categories (19% Autism Spectrum Disorder, 44% Epilepsy, 28% Intellectual Disability, 9% Cerebral Palsy). Approximately half of the patients are comorbid for one or more of the other disorders. The control patients consist of healthy family members of the affected patient group. Since family members share many common DNA features this will help us better identify and hone in on disease causing variants more effectively.
- iPSC lines have not yet been returned from these patients so there are no research results to report at this time. We are continuing with our recruitment efforts to reach our goal of 450 affected patients and 100 healthy controls.
The applicant is an MD/PhD trained physician scientist, whose clinical expertise is neuromuscular disorders including peripheral nerve disease. The proposal is aimed at providing a research proposal and career development plan that will allow the applicant to develop an independent research program, which attempts to bring stem cell based therapies to patients with peripheral nerve diseases. The proposal will use “adult stem cells” derived from patients with an inherited nerve disease, correct the genetic abnormality in those cells, and determine the feasibility of transplanting the genetically engineered cells back into peripheral nerve to slow disease progression.
The proposed research will benefit the State of California as it will support the career development of a uniquely trained physician scientist to establish an innovative translational stem cell research program aimed toward direct clinical application to patients. The cutting edge technologies proposed are directly in line with the fundamental purpose of the California Initiative for Regenerative Medicine. If successful, both scientific and patient advocate organizations would recognize that these advances came directly from the unique efforts of CIRM and the State of California to lead the world in stem cell research. Finally, as a result of funding of this award, further financial investments from private and public funding organizations would directly benefit the State in the years to come.
- During this award period we have made significant progress. We have established induced pluripotent stem cell (iPSC) lines from four patients with Charcot-Marie-Tooth disease type 1A (CMT1A) due to the PMP22 duplication. We have validated our strategy to genetically engineer induced pluripotent stem cells from patients with inherited neuropathy, and have genetically engineered several patient lines. We further have begun to differentiate these iPSCs into Schwann cell precursors, to begin to investigate cell type specific defects that cause peripheral neurodegeneration in patients with CMT1A. Finally we have imported and characterized a transgenic rat model of CMT1A in order to begin to investigate the ability to inject iPSC derived Schwann cell precursors into rodent nerves as a possible neuroprotective strategy.
- During this reporting period we developed genetically corrected induced pluripotent stem cell lines from patients with CMT1A. We improved and validated a novel method for differentiating Schwann cells from iPSCs, and used this to generate human Schwann cells from patients and controls. Finally we have initiated pilot studies injecting human iPSC derived Schwann cells into the peripheral nerves of rats with myelin diseases to determine whether cell replacement therapy is a viable strategy in these disorders.
White matter is the infrastructure of the brain, providing conduits for communication between neural regions. White matter continues to mature from birth until early adulthood, particularly in regions of brain critical for higher cognitive functions. However, the precise timing of white matter maturation in the various neural circuits is not well described, and the mechanisms controlling white matter developmental/maturation are poorly understood. White matter is conceptually like wires and their insulating sheath is a substance called myelin. It is clear that neural stem and precursor cells contribute significantly to white matter maturation by forming the cells that generate myelin. In the proposed experiments, we will map the precise timing of myelination in the human brain and changes in the populations of neural precursor cells that generate myelin from birth to adulthood and define mechanisms that govern the process of white matter maturation. The resulting findings about how white matter develops may provide insights for white matter regeneration to aid in therapy for diseases such as cerebral palsy, multiple sclerosis and chemotherapy-induced cognitive dysfunction.
Diseases of white matter account for significant neurological morbidity in both children and adults in California. Understanding the cellular and molecular mechanisms that govern white matter development the may unlock clues to the regenerative potential of endogeneous stem and precursor cells in the childhood and adult brain. Although the brain continues robust white matter development throughout childhood, adolescence and young adulthood, relatively little is known about the mechanisms that orchestrate proliferation, differentiation and functional maturation of neural stem and precursor cells to generate myelin-forming oligodendrocytes during postnatal brain development. In the present proposal, we will define how white matter precursor cell populations vary with age throughout the brain and determine if and how neuronal activity instructs neural stem and precursor cell contributions to human white matter myelin maturation.
Disruption of white matter myelination is implicated in a range of neurological diseases, including cerebral palsy, multiple sclerosis, cognitive dysfunction from chemotherapy exposure, attention deficit and hyperactivity disorder (ADHD) and even psychiatric diseases such as schizophrenia. The results of these studies have the potential to elucidate clues to white matter regeneration that may benefit hundreds of thousands of Californians.
- Formation of the insulated fiber infrastructure of the human brain (called "myelin") depends upon the function of a precursor cell type called "oligodendrocyte precursor cells (OPC)". The first Aim of this study seeks to determine how OPCs differ from each other in different regions of the brain, and over different ages. Understanding this heterogeneity is important as we explore the regenerative capacity of this class of precursor cells. We have, in the past year, isolated OPCs from various regions of the human brain from individuals at various ages and are studying the molecular characteristics of these precursor cells at the single cell level in order to define distinct OPC subpopulations. We have also begun to study the functional capabilities of OPCs isolated from different brain regions. The second Aim of this study seeks to understand how interactions between electrically active neurons and OPCs affect OPC function and myelin formation. We have found that when mouse motor cortex neurons "fire" signals in such a way as to elicit a complex motor behavior, much as would happen when one practices a motor task, OPCs within that circuit respond and myelination increases. This affects the function of that circuit in a lasting way. These results indicate that neurons and OPCs interact in important ways to modulate myelination and supports the hypothesis that OPC function may play a role in learning.
- Sending neural impulses quickly down a long nerve fiber requires a specialized type of insulation called myelin, made by a cell called an oligodendrocyte that wraps itself around neuronal projections. Myelin-insulated nerve fibers make up the “white matter” of the brain, the vast tracts that connect one information-processing area of the brain to another. We have now shown that neuronal activity prompts oligodendrocyte precursor cell (OPC) proliferation and differentiation into myelin-forming oligodendrocytes. Neuronal activity also causes an increase in the thickness of the myelin sheaths within the active neural circuit, making signal transmission along the neural fiber more efficient. This was found to be true in both juvenile and in adult brains Metaphorically, it’s much like a system for improving traffic flow along roadways that are heavily used. And as with a transportation system, improving the routes that are most productive makes the whole system more efficient.
- Interestingly, some parts of the neural circuit studied showed evidence of myelin-forming precursor cell response to neuronal activity, while other parts of the active circuit did not. In related work, we are making progress towards understanding how OPCs differ in various regions of the brain, examining the molecular heterogeneity of human OPCs at a single cell level.
The use of stem cells or stem cell-derived cells to treat disease is one important goal of stem cell research. A second, important use for stem cells is the creation of cellular models of human development and disease, critical for uncovering the molecular roots of illness and testing new drugs. However, a major limitation in achieving these goals is the difficulty in manipulating human stem cells. Existing means of generating genetically modified stem cells are not ideal, as they do not preserve the normal gene regulation, are inefficient, and do not permit removal of foreign genes.
We have developed a method of genetically modifying mouse embryonic stem cells that is more efficient than traditional methods. We are adapting this approach for use with human embryonic stem cells, so that these cells can be better understood and harnessed for modeling, or even treating, human diseases. We will use this approach to create a human stem cell model of Charcot-Marie-Tooth (CMT) disease, an inherited neuropathy. How gene dysfunction leads to nerve defects in CMT is not clear, and there is no cure or specific therapy for this neurological disease. Thus, we will use our genetic tools to investigate how gene function is disrupted to cause CMT. By developing these tools and using them to gain understanding of CMT, we will illustrate how this system can be used to gain insight into other important diseases.
Although human stem cells hold the potential to generate new understanding about human biology and new approaches to important diseases, the inability to efficiently and specifically modify stem cells currently limits the pace of research. Also, there is presently no safe means of changing genes compatible with the use of the stem cells in therapies. We are developing new genetic tools to allow for the tractable manipulation of human stem cells. By accelerating diverse other stem cell research projects, these tools will enhance the scientific and economic development of California.
We will use these tools to create cellular models of Charcot-Marie-Tooth (CMT), a neurological disease with no cure that affects about 15,000 Californians. This model will facilitate understanding of the etiology of CMT, and may lead to insights that can be used to develop specific therapies.
Beyond gaining insight into CMT, the ability to engineer specific genetic changes in human stem cells will be useful for many applications, including the creation of replacement cells for personalized therapies, reporter lines for stem cell-based drug screens, and models of other diseases. Thus, our research will assist the endeavors of the stem cell community in both the public and private arenas, contributing to economic growth and new product development. This project will also train students and postdoctoral scholars in human stem cell biology, who will contribute to the economic capacity of California.
- An important use for stem cells is the creation of cellular models of human development and disease, critical for uncovering the molecular roots of illness and testing new drugs. However, a major limitation in achieving these goals is the difficulty in manipulating human stem cells. We have developed a method of genetically modifying mouse embryonic stem cells that is more efficient than traditional methods. During the first year of this project, we adapted this approach for use with human embryonic stem cells. We have also created gene trap mutations in a diversity of human embryonic stem cell genes that can be used to better harness human embryonic stem cells for modeling, or even treating, human diseases.
- An important use for stem cells is the creation of cellular models of human development and disease, critical for uncovering the molecular roots of illness and testing new drugs. However, a major limitation in achieving these goals is the difficulty in manipulating human stem cells. We have developed a method of genetically modifying mouse embryonic stem cells that is more efficient than traditional methods. During the second year of this project, we took advantage of new methods using the CRISPR/Cas9 system to develop novel approaches to modifying human embryonic stem cells. We have also created reversible gene trap mutations in a diversity of human embryonic stem cell genes that can be used to better harness human embryonic stem cells for modeling, or even treating, human diseases.
1.3 million Americans suffer chronically from spinal cord injuries (SCI); each year ~15,000 individuals sustain a new injury. For California, this means nearly 147,000 individuals are living with a SCI which can leave otherwise healthy individuals with severe deficits in movement, sensation, and autonomic function. Recovery after SCI is often limited, even after aggressive emergency treatment with steroids and surgery, followed by rehabilitation. The need to develop new treatments for SCI is pressing. We believe that stem cell therapies could provide significant functional recovery, improve quality of life, and reduce the cost of care for SCI patients. The goal of this Disease Team is to evaluate a novel cell therapy approach to SCI involving transplantation of human neural stem cells.
In 2005, the FDA authorized the world’s first clinical testing of human neural stem cell transplantation into the CNS. Since then, our research team has successfully generated clinical grade human neural stem cells for use in three clinical trials, established a favorable safety profile that now approaches five years in some subjects and includes evidence of long-term donor-cell survival. Relevant to this Disease Team, the most recent study began testing human neural stem cells in thoracic spinal cord injury. The initial group of three patients with complete injury has been successfully transplanted. The Disease Team seeks to extend the research into cervical SCI.
Neural cell transplantation holds tremendous promise for achieving spinal cord repair. In preliminary experiments, the investigators on this Disease Team showed that transplantation of both murine and human neural stem cells into animal models of SCI restore motor function. The human neural stem cells migrate extensively within the spinal cord from the injection site, promoting new myelin and synapse formation that lead to axonal repair and synaptic integrity. Given these promising proof-of-concept studies, we propose to manufacture clinical-grade human neural stem cells and execute the preclinical studies required to submit an IND application to the FDA that will support the first-in-human neural stem cell transplantation trial for cervical SCI.
Our unmatched history of three successful regulatory submissions, extensive experience in manufacturing, preclinical and clinical studies of human neural stem cells for neurologic disorders, combined with an outstanding team of basic and clinical investigators with expertise in SCI, stem cell biology, and familiarity with all the steps of clinical translation, make us an extremely competitive applicant for CIRM’s Disease Team awards. This award could ultimately lead to a successful FDA submission that will permit human testing of a new treatment approach for SCI; one that could potentially reverse paralysis and improve the patient’s quality of life.
Spinal cord injuries affect more than 147,000 Californians; the majority are injuries to the cervical level (neck region) of the spinal cord. SCI exacts a devastating toll not only on patients and families, but also results in a heavy economic impact on the state: the lifetime medical costs for an individual with a SCI can exceed $3.3 million, not including the loss of wages and productivity. In California this translates to roughly $86 billion in healthcare costs. Currently there are no approved therapies for chronic thoracic or cervical SCI.
We hope to advance our innovative cell therapy approach to treat patients who suffer cervical SCI. For the past 9 years, the assembled team (encompassing academic experts in pre-clinical SCI models, complications due to SCI, rehabilitation and industry experts in manufacturing and delivery of purified neural stem cells), has developed the appropriate SCI models and assays to elucidate the therapeutic potential of human neural stem cells for SCI repair.
Human neural stem cell transplantation holds the promise of creating a new treatment paradigm. These cells restored motor function in spinal cord injured animal models. Our therapeutic approach is based on the hypothesis that transplanted human neural stem cells mature into oligodendrocytes to remyelinate demyelinated axons, and/or form neurons to repair local spinal circuitry. Any therapy that can partially reverse some of the sequelae of SCI could substantially change the quality-of-life for patients by altering their dependence on assisted living, medical care and possibly restoring productive employment.
Through CIRM, California has emerged as a worldwide leader in stem cell research and development. If successful, this project would further CIRM’s mission and increase California’s prominence while providing SCI therapy to injured Californians. This Team already has an established track record in stem cell clinical translation. The success of this Disease Team application would also facilitate new job creation in highly specialized areas including cell manufacturing making California a unique training ground.
In summary, the potential benefit to the state of California brought by a cervical spinal cord Disease Team project would be myriad. First, a novel therapy could improve the quality of life for SCI patients, restore some function, or reverse paralysis, providing an unmet medical need to SCI patients and reducing the high cost of health care. Moreover, this Disease Team would maintain California’s prominence in the stem cell field and in clinical translation of stem cell therapies, and finally, would create new jobs in stem cell technology and manufacturing areas to complement the state’s prominence in the biotech field.
Multiple sclerosis (MS) is an autoimmune disease in which the myelin sheath that insulates neurons is destroyed, resulting in loss of proper neuronal function. Existing treatments for MS are based on strategies that suppress the immune response. While these drugs do provide benefit by reducing relapses and delaying progression (but have significant side effects), the disease invariably progresses. We are pursuing an alternative therapy aimed at regeneration of the myelin sheath through drugs that act on an endogenous stem cell population in the central nervous system termed oligodendrocyte precursor cells (OPCs). Remission in MS is largely dependent upon OPCs migrating to sites of injury and subsequently differentiating into oligodendrocytes – the cells that synthesize myelin and are capable of neuronal repair. Previous studies indicate that in progressive MS, OPCs are abundantly present at sites of damage but fail to differentiate to oligodendrocytes. As such, drug-like molecules capable of inducing OPC differentiation should have significant potential, used alone or in combination with existing immunomodulatory agents, for the treatment of MS. The objective of this project is to identify a development candidate (DC) for the treatment of multiple sclerosis (MS) that functions by directly stimulating the differentiation of the adult stem cells required for remyelination.
Multiple Sclerosis (MS) is a painful, neurodegenerative disease that leads to an impairment of physical and cognitive abilities. Patients with MS are often forced to stop working because their condition becomes so limiting. MS can interfere with a patient's ability to even perform simple routine daily activities, resulting in a decreased quality of life. Existing treatments for MS delay disease progression and minimize symptoms, however, the disease invariably progresses to a state of chronic demyelination. The goal of this project is to identify novel promyelinating drugs, based on differentiation of an endogenous stem cell population. Such drugs would be used in combination with existing immunosuppressive drugs to prevent disease progression and restore proper neuronal activity. More effective MS treatment strategies represent a major unmet medical need that could impact the roughly 50,000 Californians suffering from this disease. Clearly the development of a promyelinating therapeutic would have a significant impact on the well-being of Californians and reduce the negative economic impact on the state resulting from this degenerative disease.
- Multiple sclerosis (MS) is an autoimmune disease characterized by the destruction of the myelin sheath that insulates neurons, resulting in loss of proper neuronal function. Existing treatments for MS are based exclusively on strategies that suppress the immune response. We are pursuing an alternative stem cell-based therapeutic approach aimed at enhancing regeneration of the myelin sheath. Specifically, we are focused on the identification of drug-like molecules capable of inducing oligodendrocyte precursor cell (OPC) differentiation. To date, we have identified a series approved drugs that effectively induce OPC differentiation under tissue culture conditions. Additionally, we have demonstrated that several of these drug candidates reduce MS-like symptoms in relevant rodent models of the disease. We are currently conducting detailed pharmacology experiments to determine which of the identified molecules will serve as the best candidate for future clinical development.
- The aim of this project is to identify and characterize molecules that induce the repair of lesions in multiple sclerosis. Molecules that induce the selective differentiation of oligodendrocyte precursor cells to oligodendrocytes and thereby lead to remyelination of axons are being characterized with respect to their in vitro activity and in vivo efficacy in relevant animal models, alone and in combination with immunosuppressive drugs. This work may lead to a new regenerative therapy for multiple sclerosis that is complementary to the current immune-focused therapies.
One in every ten thousand people in the USA has Huntington's disease, and it impacts many more. Multiple generations within a family can inherit the disease, resulting in escalating health care costs and draining family resources. This highly devastating and fatal disease touches all races and socioeconomic levels, and there are currently no cures. Screening for the mutant HD gene is available, but the at-risk children of an affected parent often do not wish to be tested since there are currently no early prevention strategies or effective treatments.
We propose a novel therapy to treat HD; implantation of cells engineered to secrete Brain-Derived Neurotrophic factor (BDNF), a factor needed by neurons to remain alive and healthy, but which plummets to very low levels in HD patients due to interference by the mutant Huntingtin (htt) protein that is the hallmark of the disease. Intrastriatal implantation of mesenchymal stem cells (MSC) has significant neurorestorative effects and is safe in animal models. We have discovered that MSC are remarkably effective delivery vehicles, moving robustly through the tissue and infusing therapeutic molecules into each damaged cell that they contact. Thus we are utilizing nature's own paramedic system, but we are arming them with enhanced neurotrophic factor secretion to enhance the health of at-risk neurons. Our novel animal models will allow the therapy to be carefully tested in preparation for a phase 1 clinical trial of MSC/BDNF infusion into the brain tissue of HD patients, with the goal of restoring the health of neurons that have been damaged by the mutant htt protein.
Delivery of BDNF by MSC into the brains of HD mice is safe and has resulted in a significant reduction in their behavioral deficits, nearly back to normal levels. We are doing further work to ensure that the proposed therapy will be safe and effective, in preparation for the phase 1 clinical trial.
The significance of our studies is very high because there are currently no treatments to diminish the unrelenting decline in the numbers of medium spiny neurons in the striata of patients affected by HD. However this biological delivery system for BDNF could also be modified for other neurodegenerative disorders such as amyotrophic lateral sclerosis (ALS), spinocerebellar ataxia (SCA1), Alzheimer's Disease, and some forms of Parkinson's Disease, where neuroregeneration is needed. Development of novel stem cell therapies is extremely important for the community of HD and neurodegenerative disease researchers, patients, and families. Since HD patients unfortunately have few other options, the benefit to risk ratio for the planned trial is very high.
It is estimated that one in 10,000 CA residents have Huntington’s disease (HD). While the financial burden of HD is estimated to be in the billions, the emotional cost to friends, families, and those with or at risk for HD is immeasurable. Health care costs are extremely high for HD patients due to the long progression of the disease, often for two decades. The lost ability of HD patients to remain in the CA workforce, to support their families, and to pay taxes causes additional financial strain on the state’s economy. HD is inherited as an autosomal dominant trait, which means that 50% of the children of an HD patient will inherit the disease and will in turn pass it on to 50% of their children. Individuals diagnosed through genetic testing are at risk of losing insurance coverage in spite of reforms, and can be discriminated against for jobs, school, loans, or other applications. Since there are currently no cures or successful clinical trials to treat HD, many who are at risk are very reluctant to be tested. We are designing trials to treat HD through rescuing neurons in the earlier phases of the disease, before lives are devastated.
Mesenchymal stem cells (MSC) have been shown to have significant effects on restoring synaptic connections between damaged neurons, promoting neurite outgrowth, secreting anti-apoptotic factors in the brain, and regulating inflammation. In addition to many trials that have assessed the safety and efficacy of human MSC delivery to tissues via systemic IV infusion, MSC are also under consideration for treatment of disorders in the CNS, although few MSC clinical trials have started so far with direct delivery to brain or spinal cord tissue. Therefore we are conducting detailed studies in support of clinical trials that will feature MSC implantation into the brain, to deliver the neurotrophic factor BDNF that is lacking in HD. MSC can be transferred from one donor to the next without tissue matching because they shelter themselves from the immune system. We have demonstrated the safe and effective production of engineered molecules from human MSC for at least 18 months, in pre-clinical animal studies, and have shown with our collaborators that delivery of BDNF can have significant effects on reducing disease progression in HD rodent models.
We are developing a therapeutic strategy to treat HD, since the need is so acute. HD patient advocates are admirably among the most vocal in California about their desire for CIRM-funded cures, attending almost every public meeting of the governing board of the California Institute for Regenerative Medicine (CIRM). We are working carefully and intensely toward the first FDA-approved approved cellular therapy for HD patients which could have a major impact on those affected in California. In addition, the methods, preclinical testing models, and clincial trial design that we are developing could have far-reaching impact on the treatment of other neurodegenerative disorders.
- A) Pre-clinical: The remainder of the IND-enabling studies were designed in consultation with Biologics Consulting Group (BCG). The project will begin with the IND-enabling phase and transition through regulatory approvals and through an observational trial and the Phase I clinical trial of stem cell therapy. The project has a Preclinical unit, under the leadership of co-PI Dr. Jan Nolta, and a Clinical unit, under the leadership of PI Dr. Vicki Wheelock. The two units are well integrated, since the team has been meeting weekly since 2009 to plan the testing of MSC trials for HD. During the planning phase we had a minimum of 4 hours of HD meetings per week, and worked continually on the project. This team is truly translational, with both PIs highly dedicated to this trial and motivated by the HD community.
- Co-PI Jan Nolta, Ph.D. is Scientific Director of the UC Davis/CIRM GMP Facility, and will continue to direct ongoing IND-enabling studies for MSC/BDNF. The Pre-Clinical team will perform all IND-enabling studies at the level of GLP, and will manufacture and qualify the MSC and MSC/BDNF products in the GMP facility at UC Davis that is directed by Dr. Bauer (CMC lead). These studies are ongoing and we have been advised by BCG consulting lead Andra Miller, who was formerly Gene Therapy Group Leader at the FDA, CBER, Division of Cell and Gene Therapies, for almost a decade. BCG is assisting us with IND preparation.
- Ms. Geralyn Annett is the experienced Project Manager. She is the UCD Stem Cell Program Manager and has worked in the field of academic and industry stem cell trials for 20+ years. She will oversee the regulatory team and keep the IND-enabling studies on task to meet the milestones. GMP Facility Director Gerhard Bauer will be responsible for regulatory filings with assistance from Dr. Nolta, the CMC team, and Dr. Miller. Dr. Nolta has worked on clinical trials of stem cell gene therapy, and associated translational studies with Ms. Annett and Director Bauer for over 20 years.
- B) Clinical. The Clinical team is led by PI Dr. Vicki Wheelock, who is Director of the HDSA Center of Excellence at UC Davis and, with nurse practitioner Terry Tempkin, follows over 250 patients with HD in the UC Davis Movement Disorders clinic. The PI has extensive experience in conducting clinical trials and has already accrued HD patients to 14 clinical trials to date. The planning grant allowed us to conduct longer weekly meetings with different team members to complete planning of the proposed clinical trial.
- Weekly HD meetings during the planning phase included PI Dr. Wheelock, Co-PI Dr. Nolta, Nurse practitioner Terry Tempkin, Program Manager Geralyn Annett, Psychiatrist Dr. Lorin Scher, Neuropsychologist Dr. Sarah Farias, Social Worker Lisa Kjer, and members of the Imaging Unit led by Dr. Charles DeCarli. This team has worked together on multiple clinical trials for HD patients. Some meetings additionally included Dr. Kiarash Shahlaie, the UCD functional neurosurgeon who will perform the targeting and surgical implantation of the cells, Dr. Bauer who directs the GMP facility (and his team members), the translational team who is performing the IND-enabling studies in Rodents (they usually meet separately for 2 hours/week with Dr. Nolta), and Dr. Tarantal who is leading the IND-enabling studies in non-human primates.
- We met with our CRO, Paragon, who will be responsible for regulatory and safety filings including outcomes reports, medical and safety monitoring and management including DSMB, medical writing and quality assurance, clinical events committee- adjudicate AEs, and generate clinical study reports. Paragon will also oversee the development of the electronic case report forms, site management and monitoring, biostatistical analysis, and management of the database. We had on-site meetings and conference calls with Paragon during the planning Phase.
- Additional meetings were conducted with collaborators and consultants:
- A) Dunbar lab and Hersch lab in the US, both leaders in the HD field – for HD trial IND-enabling study research and HD mouse and patient biomarkers, respectively.
- B) Aylward lab in the US for detailed brain imaging analyses in HD.
- C) Paulsen lab for interpretation of cognitive assays in HD.
- D) Phil Starr and Dan Lim at UCSF for ClearPoint cell injection system.
- E) Bachoud-Levi lab in France for cell implantation in HD.
- F) Dr. Robert (Willie) Mays and Bob Deans, Athersys – for IND-enabling studies/regulatory
- In conclusion, the planning grant helped us to finalize plans for the proposed clinical trial and to complete our detailed plans for the remainder of the IND-enabling studies required to obtain FDA approval. These goals were accomplished through frequent meetings with key consultants and collaborators during the intense planning phase, where we completed the Disease Team application to CIRM that could potentially fund our proposed Phase I clinical trial of MSC/BDNF therapy for Huntington’s disease.