CD8⁺ T cells mediate allogeneic fetal rejection by agonistic anti-4-1BB mAb.

C57BL/6 female mice were mated with syngeneic C57BL/6 male or allogeneic DBA/2 male mice. 200μg agonistic anti-4-1BB (3E1) mAb or rat IgG as a control was injected i.p. into the mice 8, 10, 12 days post coitus. Some of the anti-4-1BB mAb-treated mice also received 400 µg per mouse of depleting anti-CD4 (GK1.5) or anti-CD8 (2.43) mAb on days 8 and 12. The values shown represent the means ± SDs of two independent experiments. P values were calculated relative to the mice receiving only anti-4-1BB mAb: **P<0.01.