Leishmania donovani: Immunomodulatory Role of 63KDa Leishmania Antigen in the Promotion of IFN-gamma Response (VL vs HIV-VL Co-infection)

Cytokine behavior of T-lymphocytes is not very clear when a patient is co-infected with Leishmania donovani and HIV. To achieve this we studied groups of patients comprising of VL infected, HIV infected and HIV-VL co-infected cases. As compared to lone infections by either of the infecting agent, the co-infection cases showed greatly diminished CD4 T-cell counts and slightly enhanced values of cytokines (IFNγ and IL4). The effect of 63 KDa antigenic fraction of L. donovani, previously reported by our group as having potential immunoprophylaxis effects, was also studied for its effect on T-cell cytokine pattern in the co-infection cases. It was interesting to find that this antigenic fraction showed an increase in the proportion of CD4 T-cells secreting IFNγ in both VL (alone) and HIV-VL co-infection groups.