Fig. 5.

Tregs infiltrate skin allografts and block accumulation of naive but not memory T cells. (A) Real-time PCR analysis was performed on skin allografts harvested from CBA RAG^−/− mice that had (Tnaive or Tmemory plus Treg) or had not (Tnaive alone or Tmemory alone) received cotransfer of 3 × 10⁵ CD25⁺CD4⁺ Tregs, along with a transfer of 1 × 10⁵ BM3 T cells. Skin allografts were harvested 10 days after transplantation and analyzed for the expression of Foxp3. Results are expressed as mRNA (units per HPRT) ± SD. Two to three grafts were analyzed per time point per experiment. (B) Mice generated as discussed previously were killed 50 days after transplantation, and pooled peripheral lymphoid tissues were analyzed for the number of BM3 T cells and CD44⁺ BM3 T cells (two to three mice analyzed per group). Data are presented as the mean ± SD.