树突状细胞单克隆抗体对大鼠心脏移植排斥反应的免疫抑制作用

Immunosuppreessive effect of monoclonal antibody to dendritic cells in cardiac allograft rats

目的：探讨树突状细胞单克隆抗体（DC McAb）对大鼠心脏移植排斥反应的免疫抑制效果及其对细胞免疫和体液免疫的影响。方法：以大鼠同种异体腹腔心脏移植为模型（Wistar→SD），应用舍DC McAb的WZD腹水按1：25（McAb-25组）和l：50（McAb-50组）稀释，心脏移植后受体腹腔注射给药7d，1 ml／d，观察移植心脏存活时间。另设非移植组，相同方法给药4～5d后处死大鼠，取脾观察DC McAb对大鼠脾淋巴细胞增殖、白细胞介素．2（IL-2）生成活性及绵羊红细胞（SRBC）免疫后抗体形成细胞功能的影响。结果：受体体内短期应用DC McAb，McAb．25组大鼠移植心脏存活时间为（19．37±2．93）d，McAb．50组为（19．13±2．25）d，而生理盐水对照组（NS组）为（8．75±1．28）d（P均〈0．01）；两McAb组脾淋巴细胞增殖、IL-2生成活性及抗sRBc抗体形成能力均明显低于对照组（P均〈0．01）。结论：DC McAb能够明显延长大鼠移植心脏存活时间，对大鼠脾淋巴细胞增殖、IL-2生成活性及抗体形成细胞功能均有明显抑制作用。

Objective： To study the immunosuppressive effect of monoclonal antibody to dendritic cell （DC McAb） on cardiac allograft rejection in rats and the variation in the cellular immunity and humoral immunity of rats caused by it in vivo. Methods： Cardiac transplantation was performed in the abdominal cavity of the recipient （Wistar→ SD）. Rejection was defined as the day of cessation of the transplanted heartbeat. Purified WZD （DC McAb） was diluted in saline to 1：25（McAb-25 group） or 1：50（McAb-50 group）, and administered by intra-peritioneal injection for 7 consecutive 1 ml/day to cardiac allograft recipients after engraftment, but for 4 or 5 consecutive 1 ml/day to untransplant SD rats. A same dose of NS was injected to the rats of NS group. Immediately upon sacrifice of rats at 5 days spleens were immunologic studied for examination of the lymphocytes proliferation, the production of interleukin-2（ IL-2）, and the levels of the antibody to SRBC. Results： The mean survival of cardiac allografts was 19.37 ± 2.93 days in McAb-25 group, 19.13 ± 2.25 days in McAb-50 group, but 8.75 ± 1.28 days in NS group （ P 〈 0.01 ）. The lymphocytes proliferation and levels of IL-2 produced by rat splenic lymphocytes in both McAb groups significantly decreased（ P 〈 0.01 ）. The levels of antibody to SRBC in rats in McAb-25 group and McAb-50 groups declined from 0.458± 0.086 to 0.207 ± 0.045 and to 0.221± 0.049, respectively（P 〈 0.01）. Conclusion： DC McAb could prolong the survival of rat cardiac allografts, and inhibit the splenic lymphocytes proliferation, the production of interleukin-2 and the levels of the antibody to SRBC of rats in vivo.