The antigenicity of chondromucoprotein.

Antibody was obtained in rabbits following immunization with porcine chondromucoprotein and complete adjuvant. Several constituents of the antigen were only revealed by prior hyaluronidase digestion, while an antigenic constituent revealed without hyaluronidase treatment was found to be shared by chondromucoproteins from several other species. Cross-reactivity was confirmed by tanned cell haemagglutination-inhibition and by delayed hypersensitivity reactions in guinea-pigs. Electrophoresis of chondromucoprotein gave some separation of the immunologically distinct constituents. The results suggest that chondromucoprotein may be made up of several species-specific proteins as well as a polysaccharide-peptide of common occurrence in several species. No evidence for antibody directed against chondroitin sulphate was found. The antibody has been used for the localization by immunofluorescence of chondromucoprotein in sections of tissue.