Infiltrating T Cells and their Role in Vitiligo
Following proinflammatory signalling in the skin, melanocyte antigens can be processed and presented by dendritic cells in the draining lymph node, resulting in the production of melanocyte-specific cytotoxic T lymphocytes and the generation of melanocyte-specific antibodies by B lymphocytes [60]. Histological studies of vitiligo lesions showed infiltration of lymphocytes at the border of depigmented lesions. These infiltrates consist mainly of CD8 + T cells, preferentially located in the dermo-epidermal borders neighbouring the melanocytes [61, 62]. CD8+ T cells are implicated in the destruction of melanocytes in vitiligo. Melanocytotoxic CD8+ T cells that express the skin homing marker, cutaneous lymphocyte-association antigen, infiltrate the lesional borders of vitiliginous skin, and their number correlates with disease extension and severity [63-65].