接种CEA重组痘苗病毒对小鼠CEA^＋肿瘤抑制作用的机制探讨

目的 探讨CEA重组痘苗病毒（rV-CEA)治疗CEA^ 肿瘤的机制。方法 以我室构建的rV_CEA，腹腔接种供体C57/BL小鼠，取其脾细胞及腹腔巨噬细胞（Mφ），分别过继转移给荷CEA^ -HePa肝癌细胞的C57/BL小鼠，检测该公共体小鼠脾细胞、腹腔Mφ及相应受体的脾细胞体外杀瘤细胞的效应，结果 接种rV-CEA的供体小鼠的脾细胞及腹腔Mφ过继免疫给受体小鼠，具有明显抑制受体CEA阳性肿瘤生长的作用，体外实验表明，该供体脾细胞及接种了供体Mφ的受体脾细胞对同一靶细胞的杀伤活性明显增强，但供体Mφ体外的细胞毒活性无明显增加，结论 rX-CEA对CEA^ 肿瘤的抑制作用，可能主要通过CEA特异性免疫反应激活T细胞而实现。Mφ作为抗原提呈细胞可通过激活T细胞而杀伤肿瘤细胞，具体机制值得进一步研究。

A Study of the inhibitoryeffect of a recombinant CEA vaccinia virus inocnlation on mouse CEA positive tumor

Aim To explore antitumor mechanism of a recombinant vaccinia virus containing the human CEA-cDNA (rV-CEA). Methods C57/BL mice were immunized three times with rV-CEA. Six weeks later, the macrophages(MΦ s)and splenocytes from rV-CEA-immunized donors were transferred to CEA＋ -HePa tnmor-bearing recipients,Meanwhile, the antitumor effects of these donor's MΦ s and splenocytes and that of the recipient's splenocytes were detected in vitro. Results The MΦ s and splenocytes from rV-CEA-immunized donors possessed strong antitumor activity in CEA-positive tumor-bearing recipients. The in vitro antitumor effect of splenocytes from mice inoculated with MΦ s from rV-CEA-immunized donors were markedly stronger than those from W-VV-immunized donors. However,the in vitro antitumor effect of the MΦ s from rV-CEA-immunized donors was the same as those from W-VV-immunized donors. Conclusion It is demonstrated that antitumor activity induced with rV-CEA may be mediated mainly by antigen present cells (the MΦ s), which activated tumor-specific T cells to kill tumor cells.