Melanocytes and Langerhans Cells

Melanocytes localize to the stratum basale and extend processes between the keratinocytes of the stratum basale and spinosum. Melanocytes produce the pigment melanin that protects against ultraviolet radiation. Melanin is produced in membrane-bound organelles called melanosomes that derive from the Golgi. Melanosomes are transported to the ends of the melanocyte processes where neighboring keratinocytes phagocytose the melanosomes. Langerhans cells are antigen-presenting cells in the immune system.