αβ TCR T-cell depletion and CD154 blockade in B6 mice prevents sensitization to BALB/c skin graft. BALB/c skin grafts were placed on B6 mice on day 0. Recipient B6 mice were pretreated with anti-αβ TCR mAb (0.1 mg/day; day −3) and/or anti-CD154 mAb (0.5 mg/day; days 0 and 3). (A) Kinetics of T-cell recovery after T-cell depletion with anti-αβ TCR. B6 mice were treated with anti-αβ TCR mAb alone or combined with anti-CD154 mAb. Peripheral blood was obtained on days 0 (before mAb treatment), 3, 15, and 30 after mAb treatment and was stained with PE-conjugated anti-αβ TCR. Data show the percentage of the αβ TCR⁺ T cells in peripheral lymphoid gate (n = 5-6 mice at each time point). Data are presented as averages plus or minus SD. (B) Survival of BALB/c skin graft in B6 mice treated with anti-CD154 mAb (n = 13) or anti-αβ TCR (n = 8) mAb alone, and both mAbs (n = 17). Recipients without mAb treatment (n = 8) or with control hamster IgG treatment (n = 5) served as controls. The grafts were monitored up to 140 days. (C) Antidonor antibody production after pretreatment with anti-αβ TCR mAb and/or anti-CD154 mAb. Sera were collected 4 weeks after skin graft and analyzed in FCXM assay. Antibody titers were reported as MFI. Data are presented as averages plus or minus SD. (D) Kinetics of antidonor antibody in B6 mice that received transplants of BALB/c skin graft and treated with anti-αβ TCR mAb or/and anti-CD154 mAb at weeks 4, 8, and 12 after skin graft enumerated by FCXM assay. ♦ represents an individual animal.