Further immunological studies of aortitis syndrome.

An elevated titer of anti-aorta antibodies was detected with a significantly higher frequency in cases of aortitis syndrome than in those of other diseases by the complement fixation test and tannic acid hemagglutination test. This finding indicates participation of immune mechanism in the development of aortitis syndrome. The direct fluorescent antibody technique disclosed that aorta antigens are present in the media and the adventitia in a reticular form surrounded by the elastic fibers. A lower titer of anti-aorta antibodies was found with aorta, previously treated with collagenase, than that with untreated aorta, suggesting that collagen might be the main part of the aorta antigen. Boyden's tannic acid hemagglutination technique as modified by Kumagai, was used to study streptococcal type specific antibodies. Most sera from patients with aortitis syndrome showed significantly high titers in one or more types. It is suggested that streptococcal infection may be one of the triggers working in its origin of the development of aortitis syndrome.