Stemgent View Institution's Website 5 articles published in JoVE Biology Freezing and Thawing Human Embryonic Stem Cells Lia Kent1 1Research and Development, Stemgent Since James Thomson et al developed a technique in 1998 to isolate and grow hES in culture, freezing cells for later use and thawing and expanding cells from a frozen stock have become important procedures performed in routine hES cell culture. Since hES cells are very sensitive to the stresses of freezing and thawing, special care must taken. Here we demonstrate the proper technique for rapidly thawing hES cells from liquid nitrogen stocks, plating them on mouse embryonic feeder cells, and slowly freezing them for long-term storage. Biology Culture and Maintenance of Human Embryonic Stem Cells Lia Kent1 1Research and Development, Stemgent This protocol demonstrates how to maintain healthy, undifferentiated human embryonic stem (ES) cells. Biology Generation of Induced Pluripotent Stem Cells by Reprogramming Human Fibroblasts with the Stemgent Human TF Lentivirus Set Dongmei Wu1, Brad Hamilton1, Charles Martin1, Yan Gao1, Mike Ye1, Shuyuan Yao1 1Research and Development, Stemgent We demonstrate the protocol for the generation of induced pluripotent stem cells from human somatic cells using lentivirus-mediated delivery of the human factors Oct4, Sox2, Nanog, and Lin28. Pluripotency was confirmed by morphology and the presence of embryonic stem (ES) cell-specific markers. Biology The use of SC1 (Pluripotin) to Support mESC Self-renewal in the Absence of LIF Wen Xiong1, Yan Gao1, Xun Cheng1, Charles Martin1, Dongmei Wu1, Shuyuan Yao1, Min-Ju Kim2, Yang Liu1 1Research and Development, Stemgent, 2Product Marketing, Stemgent SC1 functions through dual inhibition of Ras- GAP and ERK1. We tested the function of SC1 in supporting mouse ES cell self-renewal in the absence of LIF and showed that SC1 is able to maintain self-renewal of mouse ES cell cultures. Biology Generation of Induced Pluripotent Stem Cells by Reprogramming Mouse Embryonic Fibroblasts with a Four Transcription Factor, Doxycycline Inducible Lentiviral Transduction System Brad Hamilton1, Qiang Feng1, Mike Ye1, G Grant Welstead2 1Stemgent, 2Whitehead Institute for Biomedical Research, MIT - Massachusetts Institute of Technology The Stemgent Dox Inducible Mouse TF Lentivirus Set can reprogram mouse embryonic fibroblasts (MEFs) to induced pluripotent stem (iPS) cells. Here we demonstrate the protocol for DOX-inducible expression of mouse reprogramming transcription factors Oct4, Sox2, Klf4 and c-Myc to generate iPS colonies that express common mES pluripotency markers.