Abstract
Sera from cases of rheumatic disorder were tested against antigen extracted from human prostate by the haemagglutination method. The reactions were compared with those obtained using antigens from liver, kidney, and colon. It was found that most cases of Reiter's syndrome, ankylosing spondylitis, and some of uveitis possess circulating antibodies to prostate tissue. The significance of this result in cases of Reiter's syndrome is discussed and compared with the results in cases of rheumatoid arthritis in which such circulating antibodies were not found. The serological pattern in these disorders is compared with that found in acute rheumatic fever, where a more severe immune disturbance is to be expected. An exact explanation for the role of auto-immunization must await further experimental evidence.