Figure 4.

B7 is required for induction of peripheral tolerance. (a) T cells from B7DKO H-Y pregnant females were compared with B7DKO H-Y nonpregnant females for T3.70 expression. (b) H-Y–specific T cells from B7DKO d18 pregnants do not exhibit decreased CTL activity. 4 × 10⁶ CFSE-labeled spleen cells from B7DKO H-Y mice were cultured with 1 μM peptide for 72 h, harvested, and cultured with EL-4 cells in the absence or presence of peptide for 4 h. EL-4 target cells were then analyzed for expression of Annexin V by flow cytometry. Results represent pooled data from multiple experiments. (B7DKO nonpregnant, n = 3; B7DKO d18, n = 3).