van den Boorn JG, Konijnenberg D, Dellemijn TA, van der Veen JP, Bos JD, Melief CJ, Vyth-Dreese FA, Luiten RM.

1Department of Dermatology, Netherlands Institute for Pigment Disorders, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.

In vitiligo, cytotoxic T cells infiltrating the

perilesional margin are suspected to be involved

in the pathogenesis of the disease. However, it

remains to be elucidated whether these T cells

are a cause or a consequence of the

depigmentation process. T cells we obtained

from perilesional skin biopsies, were significantly

enriched for melanocyte antigen recognition,

compared with healthy skin-infiltrating T cells,

and were reactive to melanocyte antigen-specific

stimulation. Using a skin explant model, we were

able to dissect the in situ activities of

perilesional T cells in the effector phase of

depigmentation. We show that these T cells

could infiltrate autologous normally pigmented

skin explants and efficiently kill melanocytes

within this microenvironment. Interestingly,

melanocyte