Isolation of Alpha fetoprotein from colorectal tumor homogenates and optimizing the binding conditions with its 125I-antibody

Abstract

The aim of this work is to partially purify Alpha fetoprotein (AFP) from homogenates of human colorectal (colon and rectum) tumors. The homogenates used in this work were collected from two patients groups. Group I consists of 13 patients with benign colorectal tumor and group two (II) consists of 21 patients suffering from colorectal cancer. The results revealed that the elution profile gave two peaks by using Sephadex G 200, the first peak with high molecular weight representing the complex and the second peak represents a free antibody. The optimum conditions of binding of the partially purified AFP with 125I-anti AFP antibody were carried out. Protein amounts (52μg.ml-1 ) for benign and (81μg.ml-1 ) for malignant, tracer antibody (1.44 mg/ml) for benign and (2.16mg/ml) for malignant group. The optimum pH was 7.4 for benign and malignant. The optimum time and temperature were (180 min and 37oC) for benign and (180 min and 25oC) for malignant groups.