[Effect of trypsin on the development of a humoral immune response and of delayed hypersensitivity]

Trypsin was found to stimulate the development of humoral immune response to the thymus-dependent antigen when administered simultaneously with immunization and to exert no influence on this form of immune response being injected 4 days after immunization. Trypsin fails to affect the development of humoral immune response induced by the thymus-independent antigen. Trypsin was shown to enhance the development of hypersensitivity of delayed type at administration simultaneously with the sensitizing or resolving dose of the antigen. Trypsin appeared to attenuate the antigen-specific immunosuppressing effect of lymphocytes of the hyperimmunized animal spleen.