Generation of Novel Rat and Human Pluripotent Stem Cells by Reprogramming and Chemical Approaches

Although embryonic stem cells (ESCs) have been established from mice since 1981, attempts to derive its counterparts from various other mammals, including rats, have not succeeded. Recently, induced pluripotent stem cells (iPSCs) have been generated from both mouse and human somatic cells by genetic transduction. We had successfully established novel rat iPSCs (riPSCs), which can be homogenously maintained by LIF and a cocktail of ALK5 inhibitor, GSK3 inhibitor and MEK inhibitor. riPSCs share conventional mouse ESC characteristics and most importantly can contribute extensively to chimeras. We also generated novel human iPSCs (hiPSCs) with “mouse ESC-like” characteristics, which can be surprisingly maintained in culture in the presence of MEK inhibitor and ALK5 inhibitor.