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Proliferation in vitro of melanophores from Xenopus laevis.

Melanophores of wild-type and periodic albino mutants of Xenopus laevis were successfully cultured in vitro. They proliferated in the presence of alpha-melanocyte-stimulating hormone (alpha-MSH or cyclic adenosine monophosphate (cAMP) at a doubling time of 8-10 days. These proliferating melanophores retained their phenotypes, ability to synthesize melanin, and melanin-dispersing response to MSH stimulation. Neither depigmentation nor selective cell death of periodic albino melanophores was observed for at least 4 months during the cultivation.