FIG 5.
rRABV-mBAFF induces greater VNA titers without expanding GC B cell populations. C57BL/6 mice were immunized i.m. with 100 μl sterile PBS (n = 2), 105 FFU rRABV (n = 4), or 105 FFU rRABV-mBAFF (n = 6). On day 7 postimmunization, sera and inguinal lymph nodes were collected. Lymph nodes were homogenized, and cells were stained with allophycocyanin-Cy7 α-B220, PE-Cy7 α-CD95, and FITC α-GL7 and analyzed by flow cytometry. (A) Representative gating strategies to identify B220+ B cells are shown. (B) Contour plots of the B220+ B cells were then subgated for CD95hi GL7hi GC B cells, with representative gates shown. (C) Quantitative data of the number of GC B cells per 100,000 B cells is presented as the means ± SEM. (D) VNA titers at day 7 postimmunization were determined by RFFIT on pooled serum. Neutralization titers were normalized to IU/ml using the WHO anti-rabies virus antibody reference standard. Unpaired, two-tailed t tests were used to compare groups (*, P < 0.05).