Study of Anti-germ Cell Tumor Antibody in Testicular Tumor Cell Growth and its Evaluation for Clinical Application

用石蜡包埋的人睾丸腺瘤组织块，从生殖细胞及生殖细胞肿瘤中获得特异性单克隆抗体5G 9，并以此作为免疫原。这种抗体与胚胎和成年睾丸中精子发生阶段特异性过程中的物质反应。本研究的结果为抗体的反应分析及其临床应用提供了依据. 5G 9的生化研究通过Western印迹测量显示该抗体是分子量为29 KD的IG M类蛋白。5G 9与正常组织的免疫组化研究睾丸生殖细胞和原始生殖细胞染色阳性，而精母细胞、精子细胞、精子、间质细胞和支持细胞染色阴性. 5G 9与恶性肿瘤组织的免疫组化研究典型卵巢癌、精细胞卵巢癌、胚胎癌和绒毛膜癌均为阳性，但后两者阳性率高于前两者。泌尿系恶性肿瘤，如卵黄囊瘤、畸胎瘤、恶性淋巴瘤等，染色阴性。人睾丸生殖细胞系ITO-II也呈阳性. 5G 9在睾丸诊断中的临床应用评价无精症和少精症的阳性率分别为80%和79%。2例少精子症患者精子染色阳性，但染色率差异无统计学意义。特发性无精子症表现出79%的阴性率。5G 9在正常睾丸被认为是染色精原细胞阳性，并确定周围的条件下，而不是在检测存在的精原细胞邻近的基底膜是有用的。因此，建议使用5G 9的免疫组化研究可能是有用的，以评估水平的残余精子的精子生产能力的无精子症和少精子症。

A specific monoclonal antibody, 5G9, was obtained from germ cell and germ cell tumor by making paraffin-embedded blocks of human testicular seminoma and used as the immunogen. This antibody reacts with the substance in the stage-specific process of spermatogenesis in embryos and adult testicles. The result of this study show the analysis of the reaction to the antibody and its possible clinical application.1. Biochemical studies of 5G9Measurements by Western blot revealed this antibody to be a protein of the Ig M class with a molecular weight of 29KD.2. Immunohistochemical studies of 5G9 and normal tissuesTesticular germ cell and primordial germ cell stained positive ; however, spermatocytes, spermatids, spermatozoa, leydig cell and sertoli cell stained negative.3. Immunohistochemical studies of 5G9 and malignant tumor tissuesAll specimens of typical seminoma, spermatocytic seminoma, embryonal carcinoma, and choriocarcinoma stained positive ; however, the positive rate for the latter two was higher than for the former two. Urological malignant tumors, such as yolk sac tumor, teratoma, malignant lymphoma etc., stained negative. Human testicular germ cell line ITO-II also stained positive.4. Evaluation of 5G9 for clinical application in testicular diagnosisThe positive rate for azoospermia and oligozospermia was 80% and 79%, respectively. Two cases of oligozospermia which spermatozoon stained positive, but no significant difference was detected in the rate of stain. Idiopathic azoospermia showed a 79% negative rate.5G9 in normal testicles is considered to stain spermatogonia positively, and to be useful in determining the condition around the basement membrane rather than in detecting the existence of spermatogonia adjacent to the basement membrane. It is therefore suggested that immunohistochemical studies using 5G9 could be useful in evaluating the level of the residual sperm-producing ability of both azzospermia and aoligozospermia.