Cloning Mice and Men: Prohibiting the Use of iPS Cells for Human Reproductive Cloning (original) (raw)
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Previous studies demonstrated that induced pluripotent stem (iPS) cells could produce viable mice through tetraploid complementation, which was thought to be the most stringent test for pluripotency. However, these highly pluripotent iPS cells were previously reported to be generated from fibroblasts of embryonic origin. Achieving fully pluripotent iPS cells from multiple cell types, especially easily accessible adult tissues, will lead to a much greater clinical impact. We successfully generated high-pluripotency iPS cells from adult tail tip fibroblasts (TTF) that resulted in viable, full-term, fertile TTF-iPS animals with no obvious teratoma formation or other developmental abnormalities. Comparison of iPS cells from embryonic origin (MEF), progenitor cells (neural stem cells) or differentiated somatic cells (TTF) reveals that fully pluripotent developmental potential can be reached by each cell type, although with different induction efficiencies. This work provides the means for studying the mechanisms and regulation of direct reprogramming, and has encouraging implications for future clinical applications and therapeutic interventions.
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Stem Cell Research
We generated three human induced pluripotent stem cell (hiPSC) sublines from human dermal fibroblasts (HDF) (MZT05) generated from a skin biopsy donated from a previously fertile woman. The skin biopsy was broadly consented for generating hiPSC lines for biomedical research, including unique consent specifically for studying human fertility, infertility and germ cell differentiation. hiPSCs were reprogrammed using Sendai virus vectors and were subsequently positive for markers of self-renewal. Pluripotency was further verified using PluriTest analysis and in vitro differentiation was tested using Taqman Real-Time PCR assays. These sublines serve as controls for hiPSC research projects aimed at understanding the cell and molecular regulation of female fertility. Resource Table Unique stem cell lines identifier UCLAi005-A UCLAi005-B UCLAi005-C Alternative names of stem cell lines MZT05-D MZT05-F MZT05-L Institution UCLA Contact information of distributor
Induced pluripotent stem cells in reproductive medicine
Reproductive Medicine and Biology
Despite recent advances in reproductive medicine, there are still no effective treatments for severe infertility caused by congenital absence of germ cells or gonadotoxic treatments during prepubertal childhood. However, the development of technologies for germ cell formation from stem cells in vitro, induction of pluripotency from somatic cells, and production of patient-specific pluripotent stem cells may provide new solutions for treating these severe fertility problems. It may be possible to produce germ cells in vitro from our own somatic cells that can be used to restore fertility. In addition, these technologies may also bring about novel therapies by helping to elucidate the mechanisms of human germ cell development. In this review, we describe the current approaches for obtaining germ cells from pluripotent stem cells, and provide basic information about induction of pluripotency and germ cell development.