Host NKT cells and donor CD4⁺CD25⁺ T cells inhibit accumulation of donor CD8⁺ T cells in TLI/ATS-conditioned host tissues. (A) Representative analyses of gated donor H-2K^b+TCRαβ⁺ cells, showing CD4 versus CD8 in spleen, MLN, and colon at day 6 after bone marrow and splenocyte transplantation in TBI/ATS-conditioned BALB/c hosts given wild-type C57BL/6 transplants and in TLI/ATS-conditioned hosts in the following groups: wild-type BALB/c hosts given untreated C57BL/6 transplants, wild-type BALB/c hosts given CD25⁺ T cell–depleted C57BL/6 transplants, invariant NKT cell–deficient Jα18^−/− BALB/c hosts given untreated C57BL/6 transplants, and Jα18^−/− BALB/c hosts receiving 0.5 × 10⁶ purified wild-type BALB/c NKT cells 4 hours before either untreated or CD25 T cell–depleted C57BL/6 transplants. Percentages of CD4 or CD8 T cells are shown enclosed in boxes. (B) Comparison of mean absolute number (± SE; ×10⁶) of H-2K^b+CD8⁺TCRαβ⁺ cells isolated at day 6 from the colon of groups shown in panel A. n = 4-8 per group.