Bdep inhibits CD8⁺ T-cell proliferation in vitro. CD8⁺ T cells were purified from the spleens of BALB/c naïve mice (Bc naïve), platelet immunized CD61 KO mice (KO ND), and platelet immunized CD61 KO mice that received Bdep therapy during immunization (KO Bdep), and stained with the proliferation dye V450 and cultured in vitro with anti-CD3 ± anti-CD28/IL-2 for 72 hours. (A) Representative flow cytometic dot plot analysis of CD8⁺ T-cell proliferation when either not stimulated (top panels) or stimulated with anti-CD3/CD28 antibodies for 72 hours. A cell-division cycle is characterized by sequential halving of the V450 fluorescence. Cumulative data of (B) CD8⁺ splenic T cells stimulated with anti-CD3/anti-CD28 and (C) anti-CD3/IL-2. Data in (B-C) are expressed as the mean ± standard deviation of percent CD8⁺ T cells proliferating (n = 5-8 mice per group). Data were analyzed using one-way analysis of variance with a Tukey’s post hoc test (***P < .001; ****P < .0001). FSC, forward scatter; ns, nonsignificant; SSC, side scatter.