目的：探讨ehCGβ肿瘤基因疫苗诱生抗hCGβ抗体的抗肿瘤作用。方法：以TR421-ehCGβ质粒实施基因免疫、空载质粒为对照，ELISA法检测免疫小鼠血清中特异性抗hCGβ-IgG抗体；以3H-TdR掺入法检测灭活补体前后免疫血清对ehCG+肿瘤细胞增殖活性的抑制作用；倒置显微镜和FACS分别观察Hela细胞的形态变化及细胞凋亡情况。结果：TR421-ehCGβ质粒诱导小鼠产生高水平抗hCGβ-IgG抗体；抗hCGβ免疫血清对Hela细胞的抑制增殖作用明显强于对照血清，灭活补体后抑制率无明显变化；免疫血清的抑制作用与肿瘤细胞的hCGβ表达水平有一定的相关性；Hela细胞与免疫血清孵育后细胞死亡明显增多，但其中凋亡细胞为3.42%，与对照血清孵育细胞的凋亡（1.88%）比较无明显差异。结论：ehCGβ肿瘤基因疫苗诱生的抗hCGβ抗体以不依赖补体方式抑制ehCGβ+肿瘤细胞的增殖。

Objective：To investigate the anti-tumor effects of anti-hCGβ antibody induced by gene immunization with ectopic human chorionic gonadotropin β-subunit. Methods：Sera were collected at the indicated times from the mice immunized with plasmid TR421-ehCGβ-coding for hCGβ and mock DNA respectively and were determined the levels of anti-hCGβ antibody by ELISA. The tumor cells expressing ehCGβ were treated with different doses of sera, in which complement were or not inactivated. The proliferation and morphological change as well as apoptosis of tumor cells were detected by \[3H\]-Thymidine incorporation assay, converse-microscope and FACS, respectively. Results：All mice immunized with plasmid TR421-ehCGβ developed high levels of anti-hCGβ antibody, which could inhibit obviously the proliferation of Hela cells compared with the serum from animals immunized with mock DNA (P<0.05), even if complement was inactivated. However, the inhibition of normal serum decreased significantly after complement was inactivated. The inhibition activity of the anti-hCGβ serum correlated with the expression level of ehCGβ in the tumor cells. The number of dead Hela cells increased obviously upon being incubated with the anti-hCGβ serum, while the percentage of the apoptotic cells was only 3.42%, which had no significant difference with the cells incubated with the normal serum (1.88%). Conclusion：The anti-hCGβ antibody induced by gene immunization had significant inhibitory influence on the proliferation of tumor cells expression ehCGβ in complement-independent manner.

国家杰出青年科学基金研究计划（39925031）和国家重点基础研究发展计划（2001CB510006）