Immunological aspects of aortitis syndrome.

1. Anti-aortic antibodies were frequently detected from the sera of patients with aortitis syndrome. 2. Aortic antigens were demonstrated to exist mainly in the media. The antigenicity was inactivated by collagenase, trypsin and pepsin, but not by DNase-I. Analyses of aortic antigens were also made by ultracentrifugation and column chromatography. 3. Experimental arteritis could be produced in animals by isologous active immunization and heterologous passive immunization. 4. From these results, participation of antigen-antibody reaction in the development of the disease has been speculated. Possible role of streptococcal infection as one of the trigger mechanisms in antibody production has been suggested in combination with evidence indicating hypersensitivity of the patients to infections.