Mbd3 Promotes Reprogramming of Primary Human Fibroblasts.

Mbd3 (Methyl-CpG binding domain protein), a core member of NuRD (nucleosome remodelling and deacetylation) is essential for embryogenesis. However, its role in reprogramming of somatic cells into induced pluripotent stem cells (iPSC) remains controversial. Some reports suggest that Mbd3 inhibits pluripotency, whilst others show that it greatly enhances reprogramming efficiency. Our study is the first to assess the role of on reprogramming of primary human fibroblasts using Yamanaka episomal plasmids (Reprogramming factors (RF) under feeder-free conditions. We showed that shRNA-mediated partial depletion of resulted in ＞5-fold reduction in the efficiency of reprogramming of primary human fibroblasts. Furthermore, iPSC that emerged after knock-down of were incapable of trilineage differentiation even though they expressed all markers of pluripotency. In contrast, over-expression of the isoform along with the Yamanaka episomal plasmids increased the number of fibroblast derived iPSC colonies by at least two-fold. The resulting colonies were capable of trilineage differentiation. Our results, therefore, suggest that appears to play an important role in reprogramming of primary human fibroblasts, which provides further insight into the biology of reprogramming but also has direct implication for translation of iPSC to clinic.