[Role of costimulating molecule CD86 in maternal-fetal immune regulation].
OBJECTIVE: To evaluate the role of costimulating molecule CD86 in maternal-fetal immune regulation. METHODS: In abortion-prone (CBA x DBA/2) matings and non-abortion-prone (CBA x BALB/c) matings, the pregnant CBA females were injected intraperitoneally by purified rat anti-murine CD86 monoclonal antibody (mAb) with dosage of 100 micrograms at day 4, 6, 8 and 10 of gestation respectively, or injected only once at day 4 of gestation, or injected with purified rat IgG as control. The resorbing and non-resorbing embryos were enumerated at day 14 of gestation. RESULTS: The embryo resorbing rate in CBA x DBA/2 matings was 27.78%, and that in CBA x BALB/c matings was 8.42%. After injection of anti-CD86 mAb at day 4, 6, 8, 10 of gestation, the embryo resorbing rate reduced to 9.68% (P < 0.005) in CBA x DBA/2 matings, while that was 13.54% in CBA x BALB/c matings (P > 0.05). After injection of anti-CD86 mAb only once at day 4 of gestation, the embryo resorbing rate reduced apparently to 7.14% (P < 0.001) in CBA x DBA/2 matings, while that was 11.39% (P > 0.05) in CBA x BALB/c matings. CONCLUSIONS: Blocking the costimulating signal by anti-CD86 mAb at maternal-fetal interface, especially at the prime stage of maternal-fetal recognition (periods of implantation), may result in maternal-fetal tolerance, and hopefully the embryo resorption turns to normal pregnancy.