ANTIGEN PRESENTATION BY EPIDERMAL LANGERHANS CELLS IN EXPERIMENTAL CUTANEOUS LEISHMANIASIS

Cutaneous leishmaniasis is a disease induced by intradermal injection of leishmania promastigotes. Since the first cells the parasite encoun ters are those of the skin, the involvement of this organ in the early immune response might be relevant to the outcome of the disease. In t his study we examined the ability of epidermal langerhans cells (LC) t o become infected in vivo and to function as antigen presenting cells during the early hours of infection with Leishmania major. Our experim ents showed that LC from mice injected with parasites can present anti gen to a leishmania-specific T cell line when LC are obtained as early as four h after infection. The stimulation was specific, since LC fro m leishmania injected mice did not present antigen to an ovalbumin-spe cific T cell line nor did LC from ovalbumin-injected mice present anti gen to the leishmania specific T cell line. Despite the ability of epi dermal LC cells to present antigen, no parasites were detected in the epidermis, suggesting that these cells are not directly involved in es tablishing an infection.