LEISHMANIA-AETHIOPICA DERIVED FROM DIFFUSE LEISHMANIASIS PATIENTS PREFERENTIALLY INDUCE MESSENGER-RNA FOR INTERLEUKIN-10 WHILE THOSE FROM LOCALIZED LEISHMANIASIS PATIENTS INDUCE INTERFERON-GAMMA

Exposure of peripheral blood mononuclear cells to promastigotes of Lei shmania aethiopica derived from patients with the self-limiting, local ized form of the disease (local cutaneous leishmaniasis; LCL) preferen tially induced mRNA for interferon (IFN)-gamma but little for interleu kin (IL)-10. In contrast, stimulation of the same cells with promastig otes derived from patients with the persistent, disseminated form of t he disease (diffuse cutaneous leishmaniasis; DCL) stimulated the expre ssion of IL-10 rather than IFN-gamma. In general, parasites derived fr om LCL patients induced more expression of other cytokines tested, inc luding IL-4, IL-6, and transforming growth factor-beta, although tumor necrosis factor-alpha was equivalent in cultures stimulated with LCL or DCL promastigotes. The results suggest that the antigen-specific im munosuppression observed in DCL patients and the resulting clinical pi cture could in part be due to the properties of the infecting parasite to induce more IL-10 than IFN-gamma.