Bl-Eng2 augments CD4⁺ T cell development <i>in vivo</i>.

<p>Mice received 10⁶ adoptively transferred naïve 1807 T cells prior to vaccination <b>(A-D)</b> or no transfer <b>(E+F)</b>. Mice were subcutaneously vaccinated with 5μg calnexin and 10μg Bl-Eng2 or alum twice, two weeks apart, and then challenged intratracheally with <i>B</i>. <i>dermatitidis</i> 26199 yeast two weeks post-vaccination. At day 4 post-infection, the frequencies of IL-17 and IFN-γ producing 1807 T cells <b>(A)</b> and numbers of activated (CD44⁺) and cytokine-producing 1807 cells in the lung were enumerated by FACS <b>(B)</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 <i>ex vivo</i> with calnexin were measured by ELISA <b>(D)</b>. 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, <b>(C+E)</b>. *, 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 <b>(E)</b>. *, 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 <b>(F)</b>. 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.