RESUMEN
The role of pro-inammatory cytokine tumor necrosis factor-alpha (TNF-α) in human leishmaniasis is not fully understood. We analyzed the alterations in the plasma levels of TNF- α, soluble TNF receptor type 1 (sTNFR I), IL-17 and IL-22 in the volunteers with leishmaniasis. Blood samples were collected from patients with active cutaneous leishmaniasis (CL), the same CL patients after standard antimonial therapy as healed CL, active visceral leishmaniasis (VL) and healed VL volunteers. Levels of the cytokines were titrated on plasma samples by sandwich ELISA method. The mean level of TNF-α was significantly higher in active CL patients than healthy controls (P<0.001) and significantly reduced after treatment in the same volunteers (P<0.001). The mean level of sTNFR I was significantly higher in active CL patients than healthy controls (P<0.05). The mean level of IL-22 in plasma of the AVL patients was significantly higher than that of healthy control group (P<0.05). There is a negative correlation between the levels of TNF-α and sTNFR I and healing of CL. Measurement of cytokines in plasma samples is more feasible than cell culture in evaluation of immune response in human leishmaniasis.
RESUMEN
Immune response in BALB/c mice immunized 3 times with different doses (50 mug or 200 mug of protein) of Alum precipitated autoclaved Leishmania major (Alum-ALM) mixed with either BCG (1 x10(7); CFU) or different doses of killed Mycobacterium vaccae (1 x10(6), 1 x10(7)) was assessed. Mice immunized with low dose of Alum-ALM mixed with either BCG or low M. vaccae showed a significantly higher IFN-gamma production and a lower IL-4 level and a significantly lower parasite burden compared to the control PBS injected group. It seems that immunization with a low dose of Alum-ALM mixed with an adjuvant induces a Th1 type of immune response in susceptible BALB/c mice.