Unlike humans and mice, some animal species such as dogs have had difficulty establishing iPS cells without residual reprogramming factors. Professor Okano from Keio University and our technical founders Dr. Shiozawa and Dr. Edamura first tried out various combinations of medium conditions (e.g. addition of growth factors and small molecule compounds) and reprogramming factor gene sets using common marmoset skin and discovered a new method for establishing iPS cells which are induced into iPS cells via intermediate cells with properties similar to neural stem cells. A new iPS cell establishment method was discovered and the same effect was subsequently observed in other animal species that are known to resist pluripotency induction. The iPS cells established by this method have the ability to differentiate into trichodermal cells and primordial germ cell-like cells and the reprogramming factors have been completely eliminated making them a suitable stem cell resource for clinical applications.