Japan Team Makes iPS Cells with Low Rejection Risk

Kyoto, March 8 (Jiji Press)--A Japanese team has said it succeeded in producing induced pluripotent stem, or iPS, cells with low rejection risk by using the technology of genome editing. The outcome of the research by the team led by Akitsu Hotta, lecturer at Kyoto University's Center for iPS Cell Research and Application, will be posted on the electronic version of the U.S. journal Cell Stem Cell on Friday. Rejection occurs when the type of human leukocyte antigen (HLA) of the transplanted cell is different from that of the recipient. The risk of rejection is low when iPS cells created from people who inherited the same HLA type from their parents are transplanted into people with the same HLA type. Because the inheritance of identical HLA types is rare, however, HLA type surveys of over 150,000 people are said to be necessary to create low-rejection-risk iPS cells that can cover more than 90 pct of Japanese. The research team created iPS cells from cells of people who inherited different HLA types and turned them into blood cells after removing certain HLA genes through genome editing. These blood cells could avoid attacks by immune cells. The team sees that more than 95 pct of Japanese can be covered by creating iPS cells from people of 12 different HLA types. "We'd like to carefully check the effectiveness and the safety of the (low-rejection-risk) cells so as to actually deliver them to patients," Hotta said. END