Question

How was iPS cell made possible?

Answer 1

For understanding how iPSCs were first created, we first need to understand that embryonic stem cells, and most stem cells in general, have a bunch of transcriptional factors that keep the cell in a state of being a propagative cell instead of a terminal cell. Shinya Yamanaka isolated twenty four of these factors which were identified as important for embryonic stem cells. These twenty four factors were supplied to mouse fibroblast cells through retroviruses, which resulted in emergence of embryonic stem cell like colonies. Stem cell markers were used to remove the non-transformed cells. He and his team further cut down the number of factors required to only four (Oct4, Sox2, cMyc and Klf4) which together were sufficient to transform adult cells in to iPSCs.