Antigen-specific T-regulatory cells can extend skin graft survival time in mice

This study investigated the effects of donor antigen-specific CD4 ⁺CD25⁺ T-regulatory cells (Tregs) on skin allografts in mice. An allogeneic skin transplant model was established using donor C57BL/6 or DBA and recipient BALB/c mice. Recipients were divided into 4 groups: control group without intervention (CON; C57BL/6 to BALB/c), rapamycin gavage group (RAP; C57BL/6 to BALB/c), CD4⁺CD25⁺ Tregs-treated group (TRE; C57BL/6 to BALB/c), in which recipients received transfusions of CD4 ⁺CD25⁺ Tregs stimulated with C57BL/6-derived immature dendritic cells, and the third-party donor group (DBA; DBA to BALB/c) in which recipients received transfusions of BALB/c CD4⁺CD25⁺ Tregs stimulated with C57BL/6-derived immature dendritic cells. Mean (SD) survival time of the skin allografts in the TRE group was 17.0 (3.4) days, significantly longer than in the other groups: CON, 6.9 (1.9) days; RAP, 10.3 (3.0) days; and DBA, 10.8 (3.6) days. The TRE group demonstrated a significantly greater expression of transforming growth factor-β and interleukin (IL)10. Donor antigen-specific CD4⁺CD25⁺ Tregs effectively extend skin allograft survival in mice.