目的　探讨协同刺激分子CD86在母 胎免疫调节中的作用。方法　建立自然流产模型(CBA×DBA/ 2 )及正常妊娠模型 (CBA×BALB/c)。两种模型分别再分为 3个组 :(1)以大鼠的IgG为对照的对照组 ;(2 )于妊娠第 4、6、8、10天 ,分别给CBA孕鼠腹腔注射大鼠抗小鼠CD86单克隆抗体的多次干预组 ;(3)仅于妊娠第 4天 ,给CBA孕鼠单次腹腔注射抗CD86单克隆抗体的单次干预组。每次腹腔注射的抗体剂量均为 10 0 μg。于妊娠第 14天计算各组胚胎吸收率。 结果　 (1)自然流产模型与正常妊娠模型的对照组胚胎吸收率分别为 2 7 78%和 8 42 %。 (2 )于妊娠第 4、6、8、10天腹腔注射抗CD86单克隆抗体后 ,自然流产模型的多次干预组胚胎吸收率下降至 9 6 8% (P <0 0 5 ) ;而正常妊娠模型的多次干预组胚胎吸收率上升至 13 5 4% (P >0 0 5 )。 (3)妊娠第 4天单次腹腔注射抗CD86单克隆抗体 ,自然流产模型单次干预组的胚胎吸收率下降至 7 14% (P <0 0 0 1) ;而正常妊娠模型单次干预组的胚胎吸收率上升至 11 39% (P >0 0 5 )。结论　妊娠早期 ,尤其在胚胎对母体的致敏阶段 (着床期 ) ,阻断母 胎界面的CD86协同刺激信号 ,将诱导母体对胚胎的免疫耐受 ,从而减少胚胎吸收 ,提高妊娠成功率 Objective To investigate the role of costimulatory molecule CD86 in immune regulation of maternal fetus. Methods The spontaneous abortion model (CBA × DBA / 2) and normal pregnancy model (CBA × BALB / c) were established. The two models were subdivided into three groups: (1) control group with rat IgG as control; (2) CBA pregnant rats were intraperitoneally injected with rat antigens on days 4, 6, 8 and 10 Mouse CD86 monoclonal antibody multiple intervention group; (3) only on the 4th day of pregnancy, CBA single intraperitoneal injection of anti-CD86 monoclonal antibody single intervention group. Each intraperitoneal injection of antibody doses were 10 0 μg. On the 14th day of gestation, the embryo absorptivity of each group was calculated. Results (1) Absorption rate of embryos in control group with spontaneous abortion model and normal pregnancy model were 2 78% and 8 42% respectively. (2) After intraperitoneal injection of anti-CD86 monoclonal antibody on the 4th, 6th, 8th and 10th day of gestation, the rate of embryo resorption decreased to 96.8% (P <0 05) After repeated interventions, the embryo uptake rate increased to 13 54% (P 0 05). (3) The single intraperitoneal injection of anti-CD86 monoclonal antibody on the 4th day of gestation reduced the embryo absorptivity of spontaneous abortion model to 7 14% (P <0.01 1), while the single pregnancy intervention group The embryo uptake rate increased to 11 39% (P> 0.05). Conclusion In early pregnancy, especially in the sensitization stage of embryos to the mother (implantation), the CD86 costimulatory signal that blocks maternal-fetal interface will induce maternal immune tolerance to embryos, thereby reducing embryo absorption and improving pregnancy success rate