Killer cells in human cutaneous leishmaniasis

In French Guiana, American cutaneous leishmaniasis is localized in the skin. The host response appears to be effective since few extra- or intracellular organisms can be found in tissue lesions, and we never observed any cutaneous dissemination or visceral involvement. However, this response is not fully effective since lesions may last for months. By using immunoperoxidase techniques and monoclonal antibodies directed against various cell populations, we examined the local immune response in skin biopsies. We found a high percentage of cells with the K/NK phenotype, a variable but usually high percentage of cells with the T cell phenotype bearing TAC receptors, and moderate numbers of monocytes and B cells. These results suggest that K/NK cells could play a role in the local control of parasite dissemination.