抗HER-2加抗CD3双特异抗体抑制胃癌细胞生长的实验研究

The in vitro and in vivo antitumor effect of anti-HER-2 ＋ anti-CD3 bispecific antibody on HER-2- expressing gastric carcinoma cell lines

目的 探讨基因工程抗HER-2＋抗CD3双特异抗体（bispecificantibody，BsAb）对表达人表皮生长因子受体2（HER-2／neu）的人胃癌细胞体外及体内生长的影响。方法 用MTT方法测定Herceptin、抗CD3和BsAb抗体对胃癌细胞系SGC-7901的抑制率；免疫细胞化学法检测SGC-7901细胞的HER-2表达水平；建立裸鼠模型，将HER-2＋CD3BsAb与效应细胞（正常人外周血淋巴细胞）联合应用，观测各组荷瘤动物的肿瘤生长状况。结果 正常对照组、抗CD3单克隆抗体联合效应细胞、Herceptin联合效应细胞及HER2＋CD3 BsAb联合效应细胞肿瘤细胞的生长抑制率分别为0、（24．3±1．2）％、（56．2±2．6）％、（91．33±4．1）％各组荷瘤裸鼠与对照组的肿瘤体积为（0．86±0．02）cm^3、（0．52±0．04）cm^3、（0．20±0．06）cm^3、（0．11±0．02）cm^3，与对照组相比差异均有统计学意义（P〈0．05），其中HER-2＋CD3BsAb联合效应细胞的抑制作用更为显著，与抗CD3McAb联合效应细胞、Herceptin联合效应细胞组相比差异也有统计学意义（P〈0．05）。结论 HER-2／neu是胃癌免疫治疗的有效靶点，基因工程抗HER-2＋抗CD3BsAb在体外及体内均具有有效的抗肿瘤活性。

Objective Toevaluate ＂the effect of anti-HER-2 ＋ anti-CD3 bispicific antibody （BsAb） on the growth of gastric carcinoma cell lines SGC-7901 and xenografts in Balb/c nude mouse beating HER-2/neu-expressing human gastric carcinoma. Methods MTr assay was used to test the inhibitive rate of SGC-7901 cells treated with Hereeptin, anti-CD3 and BsAb, respectively. HER-2/neu expression level on human gastric carcinoma cell line SGC-7901 was detected by immunocytochemistry. A nude mouse xenograft model beating HER-2/neu-expressing gastric carcinoma cell line SGC-7901 was established, effector cells were combined with anti-CD3 monoclone antibody （McAb）, the humanized monoclonal antibody Herceptin and HER2 ＋ CD3 BsAb respectively. The implanted tumor volumes were measured. Results The in vitro tumor inhibitory ratio of normal control, effector cells combined with anti- CD3 McAb, Herceptin or HER2 ＋ CD3 BsAb was respectively 0, （24. 3 ±1.2） %, （56.2 ± 2. 6） % and （91.3 ±4. 1 ） %. The implated tumour volume was （0. 86 ± 0. 02） cm^3, （0. 52±0. 04 ） cm^3, （0. 20 ±0. 06）cm^3 and （0. 11±0. 02 ）cm^3, with the tumor growth significantly inhibited when compared with untreated controls （ all P 〈 0. 05 ）, and the effect was most remarkable in the group treated with HER2 ＋ CD3 BsAb combining effector cells. The growth of xenografts in HER2 ＋ CD3 BsAb combining effector cells were also significant inhibited when compared with anti-CD3 MeAb or Herceptin combining effeetor cells groups （P 〈 0. 05 ）. Conclusions HER-2/neu might be a useful target of immunotherapy in gastric carcinoma. Anti-HER2 ＋ anti-CD3 BsAb is of in vitro and in vivo antitumor effect.