Recipients of β₇^-/- donor T cells and of WT T cells generate similar levels of serum IFNγ. Lethally irradiated (1300 cGy) B10.BR recipients underwent transplantation with 5 × 10⁶ WT TCD-BM and either 1 × 10⁶ WT or β₇^-/- splenic T cells. Serum levels of IFNγ were determined by ELISA at day 7 and 14 after transplantation. Shown are combined results of 2 experiments (n = 9). P = .08 at day 7, and P = .751 at day 14.