The antigenic structure of ferritin. 1. Isolation of ferritin subunits and their immunochemical characteristics]

A method for the isolation of monomers of ferritin subunits has been developed. The procedure comprises dissociation of ferritin by treatment with thioglycolic acid in the presence of phosphate ions and subsequent gel-permeation chromatography. Ferritin and a number of its structural analogues (apoferritin, carboxymethylated ferritin, H- and L-subunits of ferritin) have been immunochemically characterized. The immunoreactivity of ferritin is shown to vary along with the degree of denaturation. Isolation of monomers of H- and L-subunits results in appearance of new antigenic sites. These "hidden" antigenic determinants are presumed to be localized in the regions of intersubunit contacts and intracapsular surface of the ferritin molecule and are responsible for the differences in immunochemical properties of its H- and L-subunits.