T-cell response in human leishmaniasis

In the present communication we provide evidence for the existence of a Th1 /Th2 dichotomy in the T-cell response to Leishmania antigens in human leish maniasis. Our data suggest that the pattern of IL-4 and IFN-gamma response is polarised in these patients. Lymphocytes from individuals recovered from cutaneous leishmaniasis (CL) responded by IFN-gamma, production following stimulation with Leishmania antigens whereas cells from patients recovered from visceral leishmaniasis (VL) showed a mixed pattern of IFN-gamma and IL -4 responses. The cells producing these cytokines were predominantly CD4 +/ -. Furthermore, IL-10 plays an important role in the development of post ka la azar dermal leishmaniasis (PKDL) from VL. The balance between the parasi tic-specific T-cell response plays an important regulatory role in determin ing the outcome of Leishmania infections in humans. (C) 1999 Elsevier Scien ce B.V. All rights reserved.