[Effect of temperature and proteolytic enzymes on the immunological properties of 2 acid neurospecific antigens].

The immunological properties of water-soluble acid neurospecific antigens A and D of the bull brain were studied as affected by heating and proteolytical enzymes (trypsin, mixture of trypsin and alpha-chymotrypsin, protease from Streptomyces griseus). The immunological activity of antigen A is not changed essentially after its heating for 20 min at a temperature of 70-80 and 24-hour proteolysis with trypsin. Heating at 90-100 C as well as hydrolysis with protease from Streptomyces griseus and mixture of trypsin with alpha-chymotrypsin for the same time decrease the immunological activity of antigen A. The immunological activity of antigen A lowers after heating for 20 minutes at a temperature of 60 C and the action of all the studied proteolytical enzymes for 24 hours. The data obtained evidence for protein nature of antigens A and D.