Intracellular cytokines.

The principal technique described in this unit was developed for detecting cytokines produced by T cells, specifically interferon gamma (IFN-gamma) and interleukin 4 (IL-4). In addition to providing information about which cytokines are being produced, it also helps to phenotypically identify the specific cells producing them. For example, CD4(+) or CD8(+) cells can be subdivided into T(H)1/T(H)2 helper cells or T(C)1/T(C)2 suppressor cells, respectively.

alpha-Melanocortin and endothelin-1 activate antiapoptotic pathways and reduce DNA damage in human melanocytes.

UV radiation is an important etiologic factor for skin cancer, including melanoma. Constitutive pigmentation and the ability to tan are considered the main photoprotective mechanism against sun-induced carcinogenesis. Pigmentation in the skin is conferred by epidermal melanocytes that synthesize and transfer melanin to keratinocytes.