人源化抗叶酸受体抗体的抗原结合活性测定

目的: 采用直接ELISA法检测人源化抗叶酸受体抗体的抗原结合活性。方法: 以固定量的重组人叶酸受体@做包被抗原,辣根过氧化酶标记的抗人IgG(H+L)为二抗,直接测定不同浓度参比品和供试品与抗原的结合活性,通过数据处理软件对结果绘图,根据供试品及参比品EC₅₀值计算供试品的相对结合力。结果: 同一批次的3支供试品分别经3次测定,相对结合活性分别为参比品的(80.61±12.19)%,(88.82±12.70)%,(103.57±6.07)%,平均值(91.0±13.72)%。3次试验的RSD分别为15.12%,14.30%,5.86%。结论: 直接ELISA法精密性良好,结果客观,影响因素少,可用于人源化叶酸受体抗体抗原结合活性的常规检测。

Objective: To determine the antigen binding activity of the humanized IgG₁ antibody against human folate receptor(FRA) alpha by ELISA directly. Methods: The reference and the samples of humanized antibody against human FRA were serially diluted and allowed to incubate with a fixed amount of human folate receptor alpha.The EC₅₀ of reference standard and the samples would be determined by fitting a 4-parameter equation.The binding potency of the samples would be expressed as a percentage of the EC₅₀ to that of the reference standard. Results: The average of the binding potency of the humanized IgG1 antibody was (91.0±13.72)%,from 3 times tests of 9 vial samples of the same batch,which meet the requirement of their quality control.The 3 times results were(80.61±12.19)%,(88.82±12.70)%and(103.57±6.07)%respectively.The RSD of each time was 15.12%,14.30%and 5.86%. Conclusion: The results showed that direct ELISA is a repeatable and stable method to detect the relative binding affinity.The method can be used as a routine analysis in the quality control of humanized anti-FRA monoclonal antibody.