ヒト胚細胞性腫瘍の分化関連糖鎖抗原の免疫学的並びに生化学的研究と臨床診断への応用

在29例胚胎癌、卵黄囊瘤、未成熟畸胎瘤和性腺及性腺外绒毛膜癌患者中，有16例用FARR法检测到了小鼠畸胎癌细胞株F9的人抗胚胎多糖抗体。而无性细胞瘤、精原细胞瘤、生殖细胞瘤和成熟畸胎瘤患者(77例)和非生殖细胞型卵巢肿瘤患者(118例)的血清均未检测到该抗体。经Sephacryl S300柱层析，得到的抗原性胚聚糖具有较高的相对分子质量(70,000以上)，并携带与单叶帆布菜凝集素-1的结合部位。在F9细胞培养上清液中也发现了抗原性胚胎多糖。用合成B型血三糖吸收患者血清，未能清除抗F9胚胎多糖的抗体。这些患者的血清对兔红细胞的血凝滴度均不高于正常范围。相反，从Ehrlich腹水肿瘤细胞中获得的-lt；α&gt；-半乳糖碳水化合物有效地抑制了患者血清与F9胚胎多糖的结合。这些结果表明，抗F9胚胎多糖的人源抗体识别有别于B血型抗原的-lt；α&gt；-半乳糖基结构，但与艾氏腹水细胞上的-lt；α&gt；-半乳糖基结构有交叉反应。

Human antibody against an embryoglycan present on a mouse teratocarcinoma cell line F9 was found in sera from 16 out of 29 patients with embryonal carcinoma, yolk sac tumor, immature teratoma, and choriocarcinoma of gonadal and extragonadal origins by Farr assay. In contrast, none of sera from patients (77 cases) with dysgerminoma, seminoma, germinoma, and mature teratoma, or patients (118 cases) with non-germ cell types of ovarian tumors contained this antibody. The antigenic embryoglycan was of high molecular weight (more than 70,000) on Sephacryl S300 column chromatography, and carried binding sites for Grifonia simplicifolia agglutinin-1. The antigenic embryoglycan was also found in F9 cell-cultured medium. Absorption of patients' sera with synthetic blood group B trisaccharides failed to remove the antibody against F9 embryoglycan. None of these patients' sera showed higher hemaggulutination titer to rabbit erythrocytes than the normal range. In contrast, <alpha> -galactosyl carbohydrates obtained from Ehrlich ascites tumor cell effectively inhibited the binding of patients' sera with F9 embryoglycan. These results indicate that the human antibody against F9 embryoglycan recognizes <alpha> -galactosyl structures, that are distinct from B blood group antigen, but are cross-reactive with <alpha> -galactosyl structures on Ehrlich ascites cells.