SPECTRAL STUDIES ON ISOLATED (125I-ANTI CA 15-3 ANTIBODY/ CA15-3) COMPLEX FROM BENIGN AND MALIGNANT IN HUMAN BREAST TUMORS

Abstract

Gel filtration technique was used to separate 125I-anti CA 15-3 antibody bound to isolated CA 15-3 complex using benign and malignant breast tissue homogenate (as CA 15-3 source) from unbound (Free) 125I-anti CA 15-3 antibody. The characterization of the complexes(125I-anti CA15-3 antibody/ CA15-3) from both benign and malignant breast tumors was carried out through the ultraviolet spectroscopic studies. Factors affecting the absorption properties of the two types of complexes such as pH, solvent polarity, spectrophotometric pH titration, and thermal stability in the presence of different concentrations of sodium chloride have been studied. Spectrophotometric pH titration of the two types of the complexes show that about (41.43%) and (44.29%) of histydyl residues are located on the surface of the two types of protein complexes (benign and malignant) respectively, while (40%) and (50%) of tyrosyl residues are buried interiorly in the complexes of (benign and malignant) respectively.