Embryonic stem cells hold great promise in regenerative medicine for the treatment of numerous diseases, injuries, and disabilities. Despite recent clinical successes, there remain significant hurdles to establishing ethically sound, scientifically feasible, and practically realistic human stem cells that engender broad public support and exhibit convincing therapeutic effectiveness. Among these hurdles are the source (embryo vs adult) of stem cells and immune rejection following transplantation. To overcome these two hurdles, our long-term goal is to develop and apply efficient technologies for deriving pluripotent, embryonic-like stem cells from a patient's own tissues for the purpose of providing "customized", patient-specific regenerative therapy. The rationale behind our long-term goal is that the destruction of human embryos to derive new embryonic stem cell lines, and the clinical complications associated with rejection of transplanted stem cells that are not recognized as "self", prevent full realization of the enormous potential of regenerative therapies using stem cells. Therefore, the overall objective of this SEED grant, which is the first step in achieving our long-term goal, is to extend and enhance existing technology for efficiently and reliably using adult human somatic cell nuclei to derive pure, pluripotent human embryonic-like stem cells. Our central hypothesis is that customized and therapeutically-useful embryonic-like stem cells can be derived from adult, human fibroblast nuclei reprogrammed in mouse oocytes. The justification for this project is that this methodology would eliminate the creation and/or destruction of human oocytes and embryos to derive patient-specific embryonic-like stem cells, preclude the need for immunosuppresvie therapy in patients receiving stem cells, and allow for the possibility of correcting inherited genetic mutations.
Statement of Benefit to California:
The research proposed here will significantly advance the field of stem cell biology, thereby promoting translational research applications that drive achievements of basic research to the patient's bedside faster and more effectively than before. By doing so, and by improving the health of the citizenry in need of regenerative medicine using stem cells, then this project will be of benefit to the State of California. In addition, this area of research will attract a broader and more diverse array of scientific experts in the field of stem cell biology to California, thereby also contributing to the advancement and development of the State's biomedical research enterprise.
SYNOPSIS: The PI is aiming to establish “ethically sound, scientifically feasible, practically realistic human stem cells that engender broad support…” In order to accomplish this the applicant proposes to generate embryonic-like stem cells derived from adult human fibroblast nuclei reprogrammed in mouse oocytes. All of this is to avoid the use of human oocytes and the creation and destruction of human embryos. This grant would be a perfect candidate for NIH funding . This proposal contains three specific aims. The first is to dedifferentiate and reprogram human fibroblast nuclei in metaphase II mouse oocytes. The second is to select for viable, pluripotent hESC-like cells from chimeras. The third is the integration and expression of a marker gene in newly-derived human embryonic-like stem cells. SIGNIFICANCE AND INNOVATION: Although this proposal has some innovative qualities, the reviewers felt that it was not responsive to the RFA since it does not directly involve human embryonic stem cells. STRENGTHS: One strength of the proposal is that the PI uses cross-species chimera formations to study nuclear reprogramming in human cells. The investigators have extensive experience in mouse SCNT and ES cell biology. The PI believes that this approach will be successful, and by the end of the CIRM seed grant the PI will successfully established one pluripotent embryonic-like stem cell line from somatic cells. WEAKNESSES: There are many shortcomings in this proposal, starting with the rationale. The PI states that the rationale behind this proposal is to avoid the creation and destruction of human embryos, yet the proposed work will produce embryos using human nuclei. There are also a number of scientific concerns. First and foremost, is the problem of nuclear/mitochondrial incompatability that has been described between a number of species including mouse and human. Thus, the proposal is fundamentally flawed at the outset. Moreover, the basis for performing these experiments relies on two flawed and non-reproducible reports in rabbit and cow. Finally, there is the fact that, almost certainly, the cell lines derived via this method will have mitochondrial heteroplasmy, which at minimum will make them useless for cell therapy. The proposal does not attempt to describe methods that might be employed to eliminate this problem. DISCUSSION: This proposal was deemed non-responsive to the RFA since it does not use hESCs or their derivatives.