FIG. 2.

LAg-specific immune responses in mice immunized via four different routes. (A) Serum samples were collected from liposomal LAg-immunized mice and assayed for LAg-specific IgG, IgG1, and IgG2a levels by ELISA. Data are presented as the absorbance at 450 nm and are means ± SE for five mice per group in duplicate wells. Data are representative of two independent experiments with similar results. (B to E) Mice were immunized and infected with L. donovani. DTH responses were measured in i.p. (B), i.v. (C), s.c. (D), and i.m. (E) immunized animals. Results are shown as means ± SE for five mice per group at the designated time points and are representative of two independent experiments with similar results. (F) Four months after infection, splenocytes derived from different vaccinated groups were stimulated with LAg (10 μg/ml) for 72 h, and the level of nitrite in the culture supernatants was assessed. Results are means ± SE for five mice per group done in duplicate and are representative of two independent experiments with similar results. *, P < 0.01; **, P < 0.001 for comparison to control groups (mice left unimmunized or immunized with empty liposomes by the respective routes).