A collaborative research team of Kitasato University, RIKEN, Organ Technologies, etc. announced in 2016 that the entire skin tissue including "hair follicles" that produce hair from induced pluripotent stem cells (iPS cells) of mice was regenerated. It was published in the American scientific journal "Science Advances" dated 4st of March.In the future, if skin tissue is formed from human iPS cells, it is expected to be useful for regenerative medicine for severe burns and injuries, congenital alopecia and alopecia.
The skin is layered, such as the epidermis and dermis, and contains hair follicles, sebaceous glands, and sweat glands.There was a regenerative medicine product that cultivates only the epidermis from human skin and uses it for the treatment of burns, etc., but this is the first time that the entire skin (skin organ system) with a complicated structure has been regenerated together.
The research team is a "CDB method" that forms aggregates called embryoid bodies (EBs) from mouse iPS cells and transplants collagen gels with multiple EBs embedded into mouse organisms to form various epithelial tissues. Developed. It is said that the "CDB method" was able to form more types of epithelial tissue than when iPS cells were transplanted alone or when a single EB was transplanted.Detailed analysis revealed that the formed epithelial tissue regenerated the skin organ system with skin appendages, similar to natural skin.Furthermore, when a "regenerated skin organ system unit" containing hair follicles was isolated from this iPS cell-derived skin organ system and transplanted subcutaneously into another mouse, the transplanted tissue engrafted without becoming cancerous and peripheral nerves. It has also been shown to connect with surrounding tissues such as the pili and arrector pili to regenerate the skin organ system, including functional hair follicles.
Currently, research on regenerative medicine using iPS cells is being actively conducted all over the world, and at RIKEN, a sheet of retinal cells prepared from iPS cells in 2014 will be transplanted to patients with age-related macular degeneration. Successful.By developing the "CDB method", the joint research group has succeeded in integrally forming not only one type of cell or one organ but also an organ system from iPS cells.In the future, it is expected to develop into clinical application to humans, and for that purpose, the transplant will regenerate the skin organ system in vitro without forming undifferentiated cells and other tissues by in vivo transplantation. It is said that it is necessary to develop it into a method.