J Invest Dermatol. 2017 Sep 5. pii: S0022-202X(17)32921-4. doi: 10.1016/j.jid.2017.07.849. [Epub ahead of print]

New Approach for the Derivation of Melanocytes from Induced Pluripotent Stem (Ips) Cells.

Kawakami T¹, Okano T², Takeuchi S², Osumi K², Soma Y², Itoh M³, Hirobe T⁴, Jimbow K⁵.

Abstract

Induced pluripotent stem (iPS) cells have the ability to differentiate into multiple cell types in the body and have an unlimited growth potential. However, iPS cell-derived melanocytes produced by existing protocols have significant limitations in developing novel strategies for regenerative medicine and cell therapies of pigmentation disorders in humans, because they involve culture in media containing fetal bovine serum (FBS) and non-physiologic agents. In this study, we established a new in vitro approach to generate iPS cell-derived human melanocytes which have higher proliferation rates and increased melanin production compared to melanocytes prepared by previously reported approaches. Importantly, our iPS cell-derived human melanocytes are prepared in FBS-free culture conditions that do not contain any non-physiologic agents. We designed two original methods, transferring black colonies by pipet and recovering black cell pellets from centrifuged medium, and numerous human iPS cell-derived melanocytes proliferated in gelatinous dishes coated with Matrigel after 12 days. We also succeeded in inducing melanin pigmentation in nude mouse skin in vivo using those human iPS cell-derived melanocytes. We propose that this new method using iPS cells established from T cells in the blood of normal human volunteers could be applied clinically to develop regenerative medicine and cell therapies for various forms of human pigmentation disorders.