Fig 4. Bl-Eng2 augments CD4⁺ T cell development in vivo.

Mice received 10⁶ adoptively transferred naïve 1807 T cells prior to vaccination (A-D) or no transfer (E+F). Mice were subcutaneously vaccinated with 5μg calnexin and 10μg Bl-Eng2 or alum twice, two weeks apart, and then challenged intratracheally with B. dermatitidis 26199 yeast two weeks post-vaccination. At day 4 post-infection, the frequencies of IL-17 and IFN-γ producing 1807 T cells (A) and numbers of activated (CD44⁺) and cytokine-producing 1807 cells in the lung were enumerated by FACS (B). Almost all of the 1807 T cells recruited to the lung were CD44⁺. Data represent the average ± SEM of two independent experiments with 8–10 mice/group. *, p < 0.05 vs. control mice vaccinated with calnexin and IFA alone and **, p < 0.05 vs. control mice vaccinated with soluble calnexin alone. Cytokines from lymph node cells stimulated ex vivo with calnexin were measured by ELISA (D). The number indicates the n-fold change of mice vaccinated with calnexin+Bl-Eng2 vs. mice vaccinated with calnexin alone. *, p < vs. all other groups. Lung CFU were counted at day 18 post-infection when naïve mice were moribund, (C+E). *, p < 0.05 vs. all other groups. Numbers reflect the n-fold change in lung CFU of mice vaccinated with calnexin and Bl-Eng2 vs. control mice vaccinated with calnexin or IFA alone. The survival of vaccinated mice was recorded for 30 days post-infection (E). *, p < 0.05 vs. all other groups. At day 4 post-infection, the number of calnexin-specific CD4⁺ T cells were enumerated by tetramer staining (F). Data represent the average ± SEM of tetramer positive cells from one of two independent experiments with 4–5 mice/group. *, p < 0.05 vs. all other groups. Cnx denotes calnexin.