Partial transfer of T-cell tolerance induced by transfusion of UV+R-treated platelets into naive recipient mice. (A) B-depleted splenocytes from mice given a single PRT-treated or untreated allogeneic PRP transfusion were adoptively transferred into naive recipient mice, and the recipients were examined for T-cell responses after a secondary allogeneic challenge with untreated allogeneic PRP transfusion. The recall responses were compared with mice given a single untreated allogeneic PRP transfusion and with nontransfused mice. PC, plasma cell. (B) Representative flow cytometry plots of pooled splenocytes prior to B-cell/plasma cell depletion (top) and after depletion (B220⁺ CD138⁺; bottom) for the Allo/Allo group (left) and Allo PRT/Allo group (right) that was used for adoptive transfer. (C-D) Heat maps show fold changes in frequency of activation markers for CD8⁺ T cells (C) and CD4⁺ T cells (D) for each group compared with the nontransfused group. (E-F) Frequency of CD44⁺ events (E) and ICOS⁺/CD28⁺ events (F) in the CD8⁺ T-cell gate. Notation indicates significance between groups. Combined data from 2 independent experiments are shown (n = 3-8 mice per group), and bars indicate mean and standard deviation. *P < .05, **P < .01, ***P < .001, ****P < .0001.