Effect of CyP treatment in sensitized recipients. Five to 7 weeks after sensitization, recipients were treated with CyP in a total dose of 200 mg/kg: 1 dose of 200 mg/kg and 2 doses of 100 mg/kg. Age-matched non-CyP treatment groups served as controls. Splenocytes were harvested and analyzed by flow cytometry on day 4. (A) Kinetics of B-cell populations (absolute number per microliter) were tested 4, 9, 15, and 30 days after CyP treatment. (B) Sera were collected from sensitized mice before treatment or 15 or 30 days after CyP treatment. FCXM assay was performed to test the change of donor-specific Abs in the sera. (C) Allogeneic BMT was performed 35 days after the first dose of CyP in 3 different groups: group 1, sensitized mice with 1 dose of CyP (200 mg/kg at day 0); group 2, sensitized mice with 2 doses of CyP (200 mg/kg at day 0 and 100 mg/kg at day 15); group 3, nonsensitized mice without CyP treatment. All recipients were conditioned with 950 cGy TBI and underwent transplantation with 80 × 106 BMCs for group 1 or 2 and 15 × 106 BMCs for group 3. BMCs were from the same donor of skin grafts. Engraftment was analyzed by flow cytometry 1 month later.
