________________________ Induced pluripotent stem cells (iPSCs) hold great promise in the areas of disease modeling and regenerative medicine and as a result have unique commercial potential. There are currently more than 300 ongoing clinical trials in stem cell therapies including the first-in-human trial using human iPSC- derived retinal pigment epithelial cells to treat macular degeneration. Another set of recent studies have shown direct reprogramming of target cells (e.g. fibroblasts) into neural or cardiac cell types via delivery of genes encoding tissue-specific transcription factors. These scientific advances may lead to new avenues for treatment of human diseases. These potential therapeutic applications, in addition to the potential of reprogrammed human cells as unique research tools, frame a substantial commercial opportunity. The initial and currently most commonly used methods of cellular reprogramming use retroviral vectors to deliver reprogramming factors into the cells. This method results in random integration of reprogramming factors into the genome, which is highly problematic for clinical use. Non- integrative methods of delivering reprogramming factors include the use of episomal DNA or Sendai Virus. These methods work well for a variety of cell types; however, they require monitoring for vector or viral clearance, resulting in a longer workflow and increased labor and reagent costs. There is a need to develop commercial tools for safe, efficient and adaptable cellular reprogramming, with a particular emphasis on non-viral approaches for research and therapy. A promising avenue for reprogramming cells involves delivering mRNA that encodes reprogramming factors. Using mRNA is especially attractive, as it dramatically reduces the risk of genomic integration, and reduces the time required for clearance of the reprogramming factors. The goal of this proposed Phase I Project is to develop an mRNA delivery system utilizing mineral coated microparticles and apply this innovative system for the generation of foot-print free iPSCs from clinically relevant cell types.
Specific aim 1 will utilize our mineral coated microparticles to deliver mRNA encoding fluorescent reporter proteins for the optimization of transfection conditions to fibroblasts and blood derived cells.
Specific aim 2 will use the optimized conditions to deliver mRNA encoding reprogramming factors to fibroblasts and blood derived cells to generate iPSCs which will be characterized for pluripotency, expansion capability and karyotype stability. This work is significant as it will improve the work flow for mRNA reprogramming in fibroblasts and will enable derivation of iPSCs from patient blood cells utilizing mRNA reprogramming. This work is innovative as it will improve mRNA delivery methods for these and other cell types, which will lead to further utilization of this technology in direct reprogramming, differentiation and in vivo applications.
_________________________ Induced pluripotent stem cells have enormous promise for regenerative medicine and treating diseases, but researchers need better methods to generate those stem cells from patient samples. We will develop a new transfection technology to deliver mRNA to cells from patient samples, to reprogram those cells to the pluripotent state.
