Figure 1.
Bim is critical for the initial apoptotic contraction of LCMV-specific CD4+ and CD8+ T cell responses. Groups of either Bim+/+ (open circles, light lines), Bim+/− (open squares, dashed lines), or Bim−/− (filled squares, dark lines) mice (n=3–5 mice/group/time point) were infected with LCMV. At the indicated times after infection, spleen cells were stained with MHC tetramers and numbers and percentages of Ag-specific T cells quantified by flow cytometry. Results show the percentages (A, C, E) and absolute number (B, D, F) ± SEM of CD8+ Db-NP396–404-specific T cells (A, B); of CD8+ Db-GP33–41-specific T cells (C, D); and of CD4+ I-Ab-GP61–80-specific T cells (E, F). Similar results were obtained for a third population of CD8+ T cells specific for Kb-NP205–212 (data not shown). Note: Bim+/− were not analyzed on day 10, and IAbgp61–80 MHC tetramer stains were not performed on day 67. Data are pooled from four independent experiments. * denotes a statistically significant difference between Bim−/− and Bim+/+ mice (at least p≤0.05 for the percentages and p≤0.002 for the total numbers; one-way ANOVA, Minitab for Windows).