Ovomucoid and ovoinhibitor isolated from chicken egg white are immunologically cross-reactive

Ovomucoid and ovoinhibitor were isolated from chicken egg white. Enzyme-linked immunosorbent assay (ELISA) and affinity chromatography of ovoinhibitor-coupled Sepharose 4B showed that about 25% of rabbit anti-ovomucoid antibody reacted with ovoinhibitor. Ovoinhibitor required about 1000 times the concentration of ovomucoid to give 50% inhibition of anti-ovomucoid antibody binding to ovoinhibitor in the plate-binding ELISA. These results suggested that ovoinhibitor possesses antigenic determinants which are conformationally homologous with those of ovomucoid and cross-react with anti-ovomucoid antibodies.