Application of monoclonal antibody, NCC-ST-439 for serodiagnosis of carcinoma patients

NCC-ST-439是一种针对胃癌异种移植物的单克隆抗体。NCC-ST-439确定的抗原为高分子糖蛋白，分子量大于5 × 10^6Da。，其表位为唾液糖残基。为了评估这种新的肿瘤相关碳水化合物抗原作为肿瘤标志物的有效性，我们开发了一种夹心放射免疫测定法。对正常供体和各种恶性和非恶性疾病患者的600多份血清样本进行了分析。临界值设为12单位/ml。在正常献血者中，97.0%（226/233）的血清抗原值为阴性，除了7份年轻女性血清样本。在恶性疾病患者中，34.2%（82/240）的抗原值为阳性，其中以胰腺癌患者64.0%（16/25）、结直肠癌复发患者66.7%（16/24）、乳腺癌复发患者54.5%（6/11）的抗原值为阳性。在非恶性疾病患者中，6.0%（7/116）的抗原值为阳性，但低于20单位/ml。胆结石、肝炎、肝硬化等良性肝胆疾病的阳性率尤其低，为4.3%（1/23）。结直肠癌患者血清系列检查显示抗原值随疾病状态而变化。我们得出结论，血清NCC-ST-439抗原与CEA和/或CA19-9的联合检测将有助于监测多种癌症。

NCC-ST-439 is a monoclonal antibody raised against a gastric carcinoma xenograft. The antigen defined by NCC-ST-439 was found to be high molecular glycoprotein, had a molecular weight more than 5x10^6Da., with sialyl-sugar residue as its epitope. A sandwich radio-immunometric assay for this new tumor-associated carbohydrate antigen was developed in order to evaluate its usefulness as a tumor marker. More than 600 serum samples from normal donors and patients with various malignant and non-malignant disorders were assayed. The cut-off value was set at 12 units/ml. In normal donors, 97.0%(226/233) of sera had a negative antigen value except for 7 serum samples from young females. In patients with malignant disorders, 34.2%(82/240) had a positive antigen value, particularly 64.0% (16/25) of patients with pancreatic carcinoma, 66.7% (16/24) of patients with recurrent colorectal carcinoma and 54.5% (6/11) of patients with recurrent breast carcinoma. In patients with non-malignant disorders, 6.0% (7/116) had a positive antigen value, but this was lower than 20 units/ml.The positive rate in benign hepatobiliary disorders including gallstones, hepatitis and liver cirrhosis was especially low at 4.3%(1/23). Serial examinations of sera from patients with colorectal carcinoma revealed that antigen value changed according to disease status. We concluded that determination of serum NCC-ST-439 antigen in combination with CEA and/or CA19-9 would be useful for monitoring a wide variety of carcinomas.