Figure 1.

Mouse-immunization schedule.

Notes: Female C57BL/6J mice 6–8 weeks old were immunized intraperitoneally with 100 µL of blank NPs (11.6 mg), H1 protein (50 µg), 1H1-NPs (50 µg H1 in 11.6 mg PLGA) and BCG (10⁵ CFUs/mice). H1-specific total IgG and subtype (IgG₁ and IgG_2a) titers were measured from sera of mice (n=8) by ELISA on days 14, 28, and 42 postimmunization. On day 43, three mice from each group were sacrificed, their splenocytes cultured, and different cytokines released in the culture supernatant were measured upon antigen stimulation. All mice were challenged witĥ5.7×10⁴ CFUs/mouse with Mtb H37Rv after 8 weeks of immunization. Five weeks postchallenge, lung and spleen bacterial load was enumerated in each mouse group (n=3). For enumeration of mean survival time, the remaining mice (n=12) were observed for the next 250 days.

Abbreviations: NPs, nanoparticles; PLGA, poly(lactic-co-glycolic acid); BCG, bacillus Calmette–Guérin.