Minimal histologic damage in the large intestine 5 days after cotransfer of CD4⁺CD25⁺CD62L⁺ Treg cells. Lethally irradiated BALB/c hosts received TCD BM or TCD BM plus 500 000 CD4⁺CD25^- T cells alone or together with 500 000 CD4⁺CD25⁺CD62L⁺ or CD4⁺CD25⁺CD62L^- T cells. Animals (n = 3 each group) were killed 5 days later, and a piece of large bowel was processed for standard H/E histology. Representative sections are shown at 1:40 magnification for recipients of (A) TCD BM alone, (B) CD4⁺CD25^- T cells, (C) CD4⁺CD25^- plus CD4⁺CD25⁺CD62L⁺ T cells, and (D) CD4⁺CD25^- plus CD4⁺CD25⁺CD62L^- T cells.