Development of an Immunoradiometric Assay (IRMA) for Binding of an 125I-anti AFP Antibody to Alpha Fetoprotein (AFP) In Gastric Adenocarcinoma And Gastric Lymphoma Tissues

Abstract

The objectives of this study were to measure the concentrations of AFP in cytosolic and nuclear fractions of gastric adenocarcinoma and gastric lymphoma tissue homogenates depending on binding studies with 125 I-anti AFP antibody. This study was also aimed to find out the optimum conditions including the AFP concentration, I-anti AFP antibody concentration, pH, temperature and time for maximum binding between 125 I-anti AFP antibody with AFP in cytosolic and nuclear fractions of gastric adenocarcinoma and gastric lymphoma tissue homogenates. Finally to evaluate the stability and recovery of the I-anti AFP antibody/AFP complex. Abstract Background: Most of previous studies have used Immunoradiometric assay (IRMA) for quantitative determination of Alpha- fetoprotein (AFP) in the sera of gastric cancer patients, but no works were recorded the analysis of AFP in gastric cancer tissues by IRMA. The purposes of the present study were to measure AFP concentrations in cytosolic and nuclear fractions of gastric adenocarcinoma and gastric lymphoma tissues by binding to an 125 I-anti AFP antibody and to find out the optimum conditions for forming the 125 I-anti AFP antibody/AFP complex. Methods: Tumor tissue samples were taken from 14 patients with gastric adenocarcinoma and 13 patients with gastric lymphoma. Preliminary tests of AFP binding to an 125 I-anti AFP antibody were performed. The optimum conditions, including the AFP concentration, 125 I-anti AFP antibody concentration, pH, temperature and time of binding the 125 I-anti AFP antibody with AFP in cytosolic and nuclear fractions of gastric cancer tissue homogenates were investigated. The stability of the 125 I-anti AFP antibody/AFP complex and the AFP recovery were also examined. Results: Comparison of biochemical studies for AFP in cytosolic and nuclear fractions of gastric adenocarcinoma and gas- tric lymphoma tissue homogenates showed that there were differences in AFP concentrations and the optimum conditions of binding with an 125 I-anti AFP antibody. Conclusion: The results revealed that the determination of AFP concentrations in gastric cancer tissues could be carried out by biochemical binding with an 125 I-anti AFP antibody. The binding percent values of the 125 I-anti AFP antibody/AFP complexes were increased at the optimum conditions. cytosolic and nuclear fractions of gastric adenocarcinoma and gastric lymphoma tissue homogenates used as the of AFP in this study. The (B/ T) % represents the binding percent of 125 I-anti AFP antibody with AFP, and then the concentrations of AFP accordingly.