As control, mice were administered with lip + LAg vaccine

intraperitoneally, whereas negative control mice received PBS or adjuvant alone (subcutaneously). Mice were then challenged with L. donovani promastigotes 10 days after vaccination. Inoculation of BALB/c mice with L. donovani strain AG83 leads to progressive infection in the liver and spleen, corresponding with hepato- and splenomegaly [4, 18]. We therefore evaluated the kinetics of increasing parasitic burden at 2 and 4 months after challenge, and the parasite loads in liver and spleen see more were quantitated as Leishman Donovan Units (Figure 1). Figure 1 Parasite burdens in vaccinated mice after L. donovani challenge infection. BALB/c mice were vaccinated subcutaneously with PBS, LAg, alum, alum + LAg, saponin and saponin + LAg, or intraperitoneally with Lip and Lip + LAg. Ten days post-immunization, mice were challenged intravenously

with 2.5 × 107 promastigotes of L. donovani. Liver (A) and spleen (B) parasite burden was measured buy Ku-0059436 2 and 4 months after challenge, and expressed as Leishman Donovan Units. Bars represent the mean ± SE of five individual mice per group, representative of two independent experiments. * p < 0.05, ** p < 0.01, *** p < 0.001 in comparison to PBS as well as free adjuvant immunized groups as assessed by a one-way ANOVA and Tukey’s multiple comparison

test. In the liver, we observed a trend of decreased Avelestat (AZD9668) parasitic load in both alum + LAg and saponin + LAg immunized mice as compared to PBS immunized control group, reaching statistical significance at 2 months postinfection (p < 0.05, Figure 1A). However, this effect was minor, and notably neither vaccine statistically improved the protective efficacy over immunization with adjuvant alone. Mice immunized with LAg alone also did not exhibit significantly reduced parasite load compared to controls, consistent with our earlier observation that free LAg administered subcutaneously did not influence parasite growth in the liver [6]. In contrast, significantly reduced parasite burden was seen following intraperitoneal immunization with lip + LAg as compared to both PBS and empty liposome immunized mice (p < 0.001) [4, 6]. At 4 months postinfection both alum + LAg and saponin + LAg immunized mice failed to maintain the slight reduction in the parasite levels seen at the 2 month time point, instead demonstrating infection levels comparable to PBS and free adjuvant-immunized controls. In contrast, lip + LAg immunized animals maintained lower levels of parasite burden versus controls (p < 0.001). Immunization with alum + LAg fails to reduce splenic L.