November 28, 2011
Circulation Research publishes commentary on results of research into immune rejection of iPS cells
The research team of Keisuke Okita, a lecturer at the Center for iPS Cell Research and Application (CiRA), Kyoto University, and CiRA Director Shinya Yamanaka published a commentary on the results of research into immune rejection of iPS cells1 in the September 16 issue of the U.S. scientific journal Circulation Research.
Cell transplantation following the production of target tissues from iPS cells is seen as a promising approach to facilitate regenerative medicine. However, the May 2011 edition of the British scientific journal Nature carries a report by Zhao et al. which suggests that iPS cells may be more likely to provoke immune reaction than embryonic stem (ES) cells2 when transplanted into syngeneic mice (Nature, May 13, 2011; 474 (7350): 212-215).
The Nature report emphasizes the need to assess iPS cells for immunogenicity3 and safety. Okita and his team recognize this need in their commentary, but point to possible deficiencies in the assessment methods used. When undertaking studies that model actual therapy based on iPS cell transplantation, they point out the importance of testing with allogeneic4 cells matched for MHC (major histocompatibility complex) 5type and of controlling immune response at the time of cell transplantation. As part of their commentary, they therefore suggest the need for a more detailed series of investigations going forward.
"Immunogenicity of induced pluripotent stem cells.'"
Okita K, Nagata N, Yamanaka S. Circulation Research 2011 Sep 16;109(7):720-721.
1 iPS cells: Induced pluripotent stem cells. iPS cells are a type of pluripotent stem cells established by introducing specific factors into somatic cells and are similar to ES cells.
2 ES cells: Embryonic stem cells. ES cells are a type of pluripotent stem cells derived from the inner cell mass of the blastocyst six or seven days after fertilization and culturing them. They can differentiate into cells of any tissue in the body.
3 Immunogenicity: The property that causes certain substances to provoke an immune reaction in the body.
4 Allogeneic transplantation: The transplantation of tissues or cells taken from one individual to a different individual.
5 MHC (major histocompatibility complex): A large gene region containing a large number of genes involved in immune reaction; known in humans as HLA (human leukocyte antigen).