01). Figure 2 Specific antibody responses in differently adjuvanted LAg vaccinated mice . Mice were immunized three times at 2-week intervals. Ten days after immunization mice were challenged with L. donovani. Serum samples were collected after the last booster (A) and 2 (B) and 4 months (C) after infection and assayed for LAg specific IgG and its isotypes IgG1 and IgG2a antibodies by ELISA. Each sample was examined in duplicate. Each bar represents TPX-0005 the mean absorbance values at 450 nm ± SE of five
individual mice per group at designated time points. The results are those from one experiment representative of two performed. Asterisks over each bar indicate significant differences in comparison to Tideglusib manufacturer control groups. *, P < 0.05; selleck inhibitor **, P < 0.01; ***, P < 0.001. Stimulation of DTH response in differently adjuvanted LAg vaccinated mice As an index of parasite antigen specific cell mediated response in vivo, DTH response was measured in vaccinated mice 10 days after last immunization and recalled at 2 and 4 months after challenge infection. Vaccinated mice with free LAg and its combination with different adjuvants displayed
significant DTH response in comparison to control groups (Figure 3; P < 0.05). However, the response by both BCG and MPL-TDM adjuvanted LAg was comparable but lower than the response induced by liposomal LAg immunization (P < 0.01). With challenge infection the response was increased progressively in LAg and its adjuvanted immunized groups and showed that the levels were significantly higher compared to the control groups at 2 and 4 months post-infection (P < 0.05). Among the differently adjuvanted groups, BCG+LAg and MPL-TDM+LAg immunized mice exhibited comparable levels of response whereas higher response was induced by the liposomal
LAg of immunized group (P < 0.05) at all time points after challenge infection. Figure 3 DTH responses in differently adjuvanted LAg vaccinated mice . Mice were immunized three times at 2-week intervals. Ten days after immunization mice were challenged with L. donovani. After the last immunization and 2 and 4 months after infection LAg-specific DTH responses were measured. The response is expressed as the difference (in mm) between the thickness of the test (LAg-injected) and control (PBS-injected) footpads at 24 h. Each bar represents the mean ± SE for five individual mice per group at designated time points. 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. Generation of IFN-γ and IL-4 response in differently adjuvanted LAg vaccinated mice Although BCG+LAg failed to induce serological response after immunization, the response was enhanced with infection and become comparable with other groups.