Establishment of a new human monoclonal antibody using mice that produce complete human antibodies and applications to cancer treatment

本研究组通过向小鼠引入完整的人抗体基因，建立了产生完全人抗体的KM小鼠，同时保留了抗体的多样性。这些小鼠能够通过抗原免疫产生人抗体。目前的研究旨在利用这些小鼠建立高特异性靶向癌细胞的人单克隆抗体（hMab），并将这些单克隆抗体用于癌症的诊断和治疗。1)建立针对子宫内膜癌的单克隆抗体用子宫内膜癌细胞系SNG-S免疫km小鼠，通过常规筛选方法筛选出与子宫内膜癌细胞发生反应的克隆（克隆10-9D），命名为hmc1。免疫组化染色显示，在54.6%的子宫内膜腺癌、76.9%的子宫颈腺癌、75%的上皮性卵巢癌和87.5%的腹膜癌标本中，hmc1的反应性呈阳性。此外，该单克隆抗体对增殖期或分泌期正常子宫内膜或正常子宫颈样本均无反应。因此发现该抗体特异性识别苗勒管癌和苗勒管相关癌，特异性高。碳水化合物分析确定该抗体的表位结构为o链碳水化合物结构，具有扩展的核心1结构，这种碳水化合物结构在人类中表达有限。2)建立卵巢癌单克隆抗体用卵巢透明细胞腺癌细胞系RMG-1免疫km小鼠，采用与1)相同的方法，选择与卵巢透明细胞腺癌细胞（克隆2- 10a）反应的克隆，命名为HMOCC-1。该抗体在83.2%（84/101）的上皮性卵巢癌标本中呈免疫组化阳性；按组织病理学亚型分，浆液性腺癌、子宫内膜样腺癌、透明细胞腺癌和粘液腺癌的阳性率分别为72.2%、73.9%、90%和90%。体外实验发现，该抗体可抑制腹膜间皮细胞和RMG-1细胞的附着。该抗体的表位结构被确定为糖蛋白与碳水化合物结构，不包括唾液酸。少

Our research group established KM mice that produce complete human antibodies while retaining antibody diversity by introduction of the complete human antibody gene to mice. These mice are able to produce human antibodies with immunization by antigen. The current investigation aimed to establish human monoclonal antibodies (hMab) that would target cancer cells with high specificity using these mice and to use these hMabs in the diagnosis and treatment of cancer.1) Establishment of a hMab to endometrial cancerKM mice were immunized with the endometrial cancer cell line SNG-S and a clone was selected that reacts with endometrial cancer cells (clone 10-9D) by conventional screening methods and named HMMC-1. Immunohistochemical staining revealed that the reactivity of HMMC-1 was positive in 54.6% of uterine endometrial adenocarcinoma specimens, 76.9% of uterine cervical adenocarcinoma specimens, 75% of epithelial ovarian cancer specimens, and 87.5% of peritoneal cancer specimens. Furthermo … More re, this monoclonal antibody does not react with either proliferative or secretory phase normal endometrium or normal uterine cervical samples. Thus this antibody was found to specifically recognize mullerian cancers and mullerian duct related cancers with high specificity.Carbohydrate analysis determined that the epitope structure for this antibody is a O-linked carbohydrate structure with an extended core 1 structure, a carbohydrate structure with limited expression in humans.2) Establishment of a hMab to ovarian cancerKM mice were immunized with the ovarian clear cell adenocarcinoma cell line RMG-1 and by the same methodology of 1), a clone was selected that reacts with ovarian clear cell adenocarcinoma cells (clone 2-10A) and named HMOCC-1. This antibody is immunohistochemically positive with 83.2% (84/101) of epithelial ovarian cancer specimens ; by histopathological subtype, it is positive with 72.2%, 73.9%, 90% and 90% of serous, endometrioid, clear cell, and mucinous adenocarcinoma respectively.In vitro, this, antibody was found to inhibit the attachment of peritoneal mesothelial cells and RMG-1 cells. The epitope structure of this antibody was determined to be a glycoprotein with a carbohydrate structure that does not include sialic acid. Less