抗前胃泌素释放肽单克隆抗体的纯化及体外对小细胞肺癌的活性

目的探讨亲和层析法纯化抗前胃泌素释放肽（PGRP）单克隆抗体（MAb）的效果，为该法纯化其他抗体提供数据依据。方法采用蛋白A-琼脂糖亲和层析法纯化含有MAb的腹腔积液，并用SDS—PAGE和酶联免疫吸附（ELISA）法分别检测其纯度和效价，用流式细胞术和免疫组织化学法检测其对小细胞肺癌细胞株NCI—H446的组织切片的生物功能。结果亲和层析法纯化前小鼠腹腔积液蛋白质质量浓度平均为23．62mg／ml；纯化前、后蛋白总量分别为148．79和146．67mg，回收率为98．58％。腹腔积液中MAb质量浓度平均为5．21mg／ml；纯化的MAb纯度达95％以上。纯化后抗体免疫学活性均高于纯化前，提高了6．90～15．40倍。结论蛋白A-琼脂糖亲和层析法可快速、高效地从小鼠腹腔积液中纯化抗PGRPMAb，且抗体具有较高的纯度，免疫学活性明显提高，能够选择性的和小细胞肺癌细胞的PGRP结合。

Purification of monoclonal antibody against PGRP and its activity for small cell lung cancer in vitro

Objective To explore the effect of purification on monoclonal antibody (MAb) against PGRP by Protein A-Sepharose affinity chromatography, and to provide some based data for the purification of other antibody using the same method. Methods The ascites which include MAb was purified by Protein A-Sepharose affinity chromatography. The purity and activity of MAb was tested by SDS-PAGE and ELISA. The biological function was identified by flow cytometer and immunohistochemistry. Results The average concentration of protein in ascites before purification is 23.62 mg/ml. Before and after purification, the total protein is 148.79 mg and 146.67 mg, respectively. The recovery coefficient of protein is 98.58%. The concentration of MAb in ascites is 5.21 mg/ml averagely. The MAb purity is more than 95 %. The immunoactivity of purified antibody is higher than that of unpurified antibody. Conclusion The purity of MAb against PGRP purified by Protein A-Sepharose affinity chromatography is very high. The immunoactivity of purified antibody is higher than that of unpurified antibody. So the ProteinA-Sepharose affinity chromatography is a rapid, convenient and reliable method for the purification of MAb Against PGRP.