001). Figure 1 Evaluation of protection against L. donovani in differently adjuvanted LAg vaccinated mice . Kinetics of liver (A) and spleen (B) parasite burden of mice immunized

intraperitoneally three times at 2-week intervals with BCG-LAg, MPL-TDM+LAg and LAg entrapped in see more cationic liposomes. Control animals received PBS or adjuvant buy PLX4032 only. At 10 days after the last immunization, mice were challenged intravenously with 2 × 107 promastigotes of L. donovani. At the designated times mice were sacrificed and LDU were calculated from the weight and microscopic examination of impression smears of liver and spleen tissues. Each bar represents the mean ± SE for five individual mice per group. The results are those from one experiment representative of two performed. Asterisks over each bar indicate significant differences in comparison to control groups. Asterisks over line indicate significant differences between groups. *, P < 0.05; **, P < 0.01; ***, P < 0.001; ns, not significant. In BALB/c mice persistence of L. donovani in the spleen causes selleck compound concomitant development of considerable organ-specific pathology similar to that seen in the human kala-azar. It was, therefore, important to evaluate the effect of vaccination in this organ. Similar to liver, mice immunized with BCG+LAg and MPL-TDM+LAg

demonstrated partial and comparable level of protection in spleen after 4 months challenge (Figure 1B; P < 0.01, compared to controls). However, liposomal LAg immunization exhibited the maximum level of reduction in splenic parasite load at both 2 and 4

months after challenge (P < 0.001, compared to controls). Antigen-specific humoral responses in differently adjuvanted LAg vaccinated mice To evaluate the humoral immune responses induced by three differently adjuvanted vaccine formulations, the serum levels of leishmanial antigen-specific IgG and its isotypes, IgG1 and IgG2a, from all the vaccinated groups were assessed by ELISA. Following immunization, IgG as well as IgG1 and IgG2a were elevated in all LAg adjuvanted immunized groups, except BCG+LAg, in which they remained at background Dichloromethane dehalogenase levels of control groups (Figure 2A). Higher levels of IgG, IgG1 and IgG2a were found in MPL-TDM+LAg immunized mice over the control groups (P < 0.05); however, the levels were low compared with liposomal LAg immunized group (P < 0.05). Importantly, the level of IgG2a was higher than that of IgG1 in both MPL-TDM+LAg and liposomal LAg immunized mice. With progressive infection, significant increase in total IgG was detected in all the immunized groups that became comparable to controls after 4 months of challenge infection (Figure 2B and 2C).