Studies on Oncotrophoblast Antigens by Monoclonal Antibodies

为了研究肿瘤滋养层细胞抗原，制备了8种与正常和/或肿瘤人滋养层细胞反应的单抗，并检测了它们与其他非滋养层细胞来源肿瘤的反应性。此外，还研究了几种抗肿瘤抗体在体内对肿瘤的亲和力。6株MoAbTM7-3、TM3-8、TM5-1、TM8-13、TM4-5和TM3-3的免疫原代培养绒毛膜癌细胞系，根据MoAb所检测的抗原分布，TM7-3和TM3-8、TM4-5和TM3-3分别表现出相似的反应模式。其中，TM7-3和TM3-8均表现出独特的反应模式。它们与绒毛膜癌，特别是细胞滋养细胞样瘤细胞有很强的反应，而在正常的绒毛中反应很弱。此外，卵巢浆液性囊性腺癌(3/4)和高分化子宫体癌(2/2)呈阳性反应。裸鼠移植绒毛膜癌(BeWo)后6天行~(131)I-TM3-8放射性核素显像，显示肿瘤显影良好。注射后第6天肿瘤及其他正常组织的放射性显示TM3-8与肿瘤有选择性结合。绒毛膜癌小鼠注射~(125)I-TM3-8后第4天行小鼠全身放射自显影。放射自显影显示肿瘤有明显的阳性显影。目前研究的MoAbs基本上都与滋养细胞或绒毛膜癌有关。然而，它们对某些类型的非滋养细胞起源的肿瘤分别有不同的反应模式。这些发现与早期关于癌细胞表型转变为滋养层细胞的报道一致。此外，对于一些MoAbs，也获得了令人鼓舞的数据，为其在临床领域进行肿瘤成像等实际应用提供了可能性。

In order to investigate oncotrophoblast antigens, 8 monoclonal antibodies (MoAbs) which react with normal and/or neoplastic human trophoblasts have been produced, and examined their reactivities with other non-trophoblast origin tumors. In addition, several MoAbs have been studied for their affinities to the tumor in vivo. Immunogene of the 6 MoAbs (TM7-3,TM3-8,TM5-1, TM8-13,TM4-5 and TM3-3) were cultured choriocarcinoma cell lines.According to the distribution of the antigens detected by the MoAbs, TM7-3 and TM3-8, TM4-5 and TM3-3 showed a similar reactive pattern respectively. Among there MoAbs, both TM7-3 and TM3-8 showed an unique reactive pattern. They demonstrated a very strong reaction with choriocarcinoma, particularly cytotrophoblast-like tumor cells, in spite of a very weak reaction in normal chorionic villi. In addition, they showed a positive reaction with ovarian serous cyst adenocarcinomas(3/4) and well differentiated uterine corpus carcinoma(2/2). Scintigraphy performed 6 days after injection of ^<131>I-labeled TM3-8 to choriocarcinoma(BeWo) transplanted nude mice, demonstrated excellent visualization of the tumor. Radioactivities of the tumor and other normal tissues at 6th days from the injection, showed a selective binding of TM3-8 to the tumor. Whole body autoradiography of mouse was performed 4 days after injection ^<125>I-labelled TM3-8 to the mice with a choriocarcinoma. The autoradiogram showed a clear positive gains restricted to the tumor.All MoAbs in the present studies are related to trophoblast or chorio- carcinoma basically. they react, however, to some kinds of non-trophoblast origin tumors in various patterns respectively. These findings, are consistent with earlier reports of cancer cells phenotypic change to trophoblast. In addition, with some of the MoAbs, encouraging data was obtained for thinking of a possibility of the practical application such as imaging of tumors in clinical field.