Preparation of human monoclonal antibodies using human B cell producing autoantibodies and analyses of novel autoantigens.

在一些患有自身免疫性疾病和恶性肿瘤的病例中，在血清中检测到针对未知抗原的自身抗体。使用单抗，我们研究了这些自身抗原和自身抗体，并分析了免疫系统。以自身免疫性疾病和恶性肿瘤患者的B细胞为材料，制备人型单抗。其中，我们经历了一例结肠癌患者的抗CEA单抗。亲本细胞包括人骨髓瘤细胞系ARH77、人浆细胞系UC729-6和小鼠骨髓瘤细胞系P3-X63-Ag8-653。我们用于融合的人细胞株产生的杂交瘤很少，但使用P3-X63-Ag8-653获得了大量的人源单抗。通过与一例胃癌患者胸腔积液中的B细胞融合，获得人源单抗3B7(Ig G)，与胃癌、结肠癌呈阳性反应，而与非癌组织不呈阳性反应。单抗3B7与自身抗原反应的分子图谱正在进一步研究中。目前，我们正在尝试用一种新开发的电融合方法从新的亲本细胞KR-4和KR-12中培育杂交瘤。

In some cases with autoimmune diseases and malignancies, autoantibodies to unknown antigens were detected in the sera. Using monoclonal antibodies, we have studied these autoantigens and autoantibodies and analysed the immune system. In order to prepare human type monoclonal antibodies, human B cells from cases with autoimmune diseases and malignancies were used. Therein we experienced a colonic cancer patient with anti-CEA monoclonal antibody. For parent cells, human myeloma cell line ARH77, human plasma cell line UC729-6 and mouse myeloma cell line P3-X63-Ag8-653 were served. Human cell lines which we used for fusion gave little hybridomas, but many human monoclonal antibodies were obtained when P3-X63-Ag8-653 was used. By a fusion with B cells in pleural effusion of a gastric cancer patient, human monoclonal antibody 3B7 (IgG) was raised, showing a staining reactivity with gastric and colonic cancers but not with non cancerous tissues. Molecular profile of autoantigen to which monoclonal antibody 3B7 reacts is under a further investigation. At present we are trying to raise hybridomas from new parent cells KR-4 and KR-12 using a newly developed electrofusion method.