Production of host-protective (IFN-gamma), host-impairing (IL-10, IL-13) and inflammatory (TNF-alpha) cytokines by PBMC from leprosy patients stimulated with mycobacterial antigens.

The production of IFNgamma, IL-10, IL-13 and TNFalpha was determined using PBMC from 7 tuberculoid (TT) and 7 lepromatous leprosy (LL) patients, after stimulation with several mycobacterial antigens, in an attempt to characterize the cytokine responses to these antigens. The results showed that TT patients displayed higher IFNgamma levels than LL patients with the mycobacterial antigens tested, but no differences in IL-10 production were observed between the two groups. MLSC antigen was associated with the lowest IFNgamma production in TT and LL groups. Only BCG could be identified with stimulation of IFNgamma production in some LL patients. The mycobacterial antigens SP+, SP- and BCG were associated with higher TNFalpha production in patients and controls, suggesting that these antigens could be involved in immunopathological effects. Our findings showed that the antigens tested were associated with a heterogeneous cytokine production in leprosy patients. Further studies are required to establish if an individual antigen can be identified as inducing a protective immune response in leprosy.