Induced pluripotent stem cells from goat fibroblasts.

Embryonic stem cells (ESCs) are a powerful model for genetic engineering, studying developmental biology, and modeling disease. To date, ESCs have been established from the mouse (Evans and Kaufman, 1981, Nature 292:154-156), non-human primates (Thomson et al., , Proc Nat Acad Sci USA 92:7844-7848), humans (Thomson et al., 1998, Science 282:1145-1147), and rats (Buehr et al., , Cell 135:1287-1298); however, the derivation of ESCs from domesticated ungulates such as goats, sheep, cattle, and pigs have not been successful. Alternatively, induced pluripotent stem cells (iPSCs) can be generated by reprogramming somatic cells with several combinations of genes encoding transcription factors (OCT3/4, SOX2, KLF4, cMYC, LIN28, and NANOG). To date, iPSCs have been isolated from various species, but only limited information is available regarding goat iPSCs (Ren et al., 2011, Cell Res 21:849-853). The objectives of this study were to generate goat iPSCs from fetal goat primary ear fibroblasts using lentiviral transduction of four human transcription factors: OCT4, SOX2, KLF4, and cMYC. The goat iPSCs were successfully generated by co-culture with mitomycin C-treated mouse embryonic fibroblasts using medium supplemented with knockout serum replacement and human basic fibroblast growth factor. The goat iPSCs colonies are flat, compact, and closely resemble human iPSCs. They have a normal karyotype; stain positive for alkaline phosphatase, OCT4, and NANOG; express endogenous pluripotency genes (OCT4, SOX2, cMYC, and NANOG); and can spontaneously differentiate into three germ layers in vitro and in vivo.

Song H ，Li H ，Huang M ，Xu D ，Gu C ，Wang Z ，Dong F ，Wang F ... -  《-》

Nuclear reprogramming with a non-integrating human RNA virus.

Driscoll CB ，Tonne JM ，El Khatib M ，Cattaneo R ，Ikeda Y ，Devaux P ... -  《Stem Cell Research & Therapy》

Inducing pluripotency in somatic cells from the snow leopard (Panthera uncia), an endangered felid.

Induced pluripotency is a new approach to produce embryonic stem-like cells from somatic cells that provides a unique means to understand both pluripotency and lineage assignment. To investigate whether this technology could be applied to endangered species, where the limited availability of gametes makes production and research on embryonic stem cells difficult, we attempted generation of induced pluripotent stem (iPS) cells from snow leopard (Panthera uncia) fibroblasts by retroviral transfection with Moloney-based retroviral vectors (pMXs) encoding four factors (OCT4, SOX2, KLF4 and cMYC). This resulted in the formation of small colonies of cells, which could not be maintained beyond four passages (P4). However, addition of NANOG, to the transfection cocktail produced stable iPS cell colonies, which formed as early as D3. Colonies of cells were selected at D5 and expanded in vitro. The resulting cell line was positive for alkaline phosphatase (AP), OCT4, NANOG, and Stage-Specific embryonic Antigen-4 (SSEA-4) at P14. RT-PCR also confirmed that endogenous OCT4 and NANOG were expressed by snow leopard iPS cells from P4. All five human transgenes were transcribed at P4, but OCT4, SOX2 and NANOG transgenes were silenced as early as P14; therefore, reprogramming of the endogenous pluripotent genes had occurred. When injected into immune-deficient mice, snow leopard iPS cells formed teratomas containing tissues representative of the three germ layers. In conclusion, this was apparently the first derivation of iPS cells from the endangered snow leopard and the first report on induced pluripotency in felid species. Addition of NANOG to the reprogramming cocktail was essential for derivation of iPS lines in this felid. The iPS cells provided a unique source of pluripotent cells with utility in conservation through cryopreservation of genetics, as a source of reprogrammed donor cells for nuclear transfer or for directed differentiation to gametes in the future.

Verma R ，Holland MK ，Temple-Smith P ，Verma PJ ... -  《-》

Reprogramming human endometrial fibroblast into induced pluripotent stem cells.

A recent breakthrough demonstrated that ectopic expression of four genes is sufficient to reprogram human fibroblasts into inducible pluripotent stem cells (iPSCs). However, it remains unknown whether human endometrial fibroblasts (EMFs) are capable of being reprogrammed into EMF-derived iPSCs (EMF-iPSCs). EMFs were obtained from donors in their third and fourth decade of life and were reprogrammed into iPSCs using retroviral transduction with Oct-4, Sox2, Klf4, and c-Myc. The EMF-iPSCs displayed the accelerated expression of endogenous Nanog and OCT-4 during reprogramming compared with EMFs. As a result, EMF-iPSC colonies that could be subcultured and propagated were established as early as 12 days after transduction. After 2 weeks of reprogramming, the human endometrial cells yielded significantly higher numbers of iPSC colonies and formed more 3D spheroid bodies than the EMFs. We have shown that human EMF-iPSCs are able to differentiate into neuronal-like cells, adipocytes, and osteocyte-like cells that express specific osteogenic genes. Human EMFs can undergo reprogramming to establish pluripotent stem cell lines in female donors by the retroviral transduction of Oct-4, Sox2, Klf4, and c-Myc.

Chen YJ ，Liou YJ ，Chang CM ，Li HY ，Chen CY ，Twu NF ，Yen MS ，Chang YL ，Peng CH ，Chiou SH ，Chen CP ，Chao KC ... -  《-》

Direct Reprogramming of Human Primordial Germ Cells into Induced Pluripotent Stem Cells: Efficient Generation of Genetically Engineered Germ Cells.

Bazley FA ，Liu CF ，Yuan X ，Hao H ，All AH ，De Los Angeles A ，Zambidis ET ，Gearhart JD ，Kerr CL ... -  《-》