Complement-fixation and hemagglutination antigens from a Chlamydial (ornithosis) agent grown in cell cultures.

Methods are described for the preparation of complement-fixation (CF) and hemagglutination (HA) antigens from the Texas turkey ornithosis agent grown in McCoy cell culture monolayers. The particulate antigens prepared for this study were satisfactory for testing mammalian sera by direct CF tests and avian sera by indirect CF or modified direct CF tests. Comparison of titers were made on human, bovine and ovine sera using direct CF tests employing antigen prepared for this study, 6 BC yolk sac antigen, and a commercially available antigen. The HA antigen agglutinated mouse erythrocytes, but it was not of value in hemagglutination inhibition tests because of "nonspecific" inhibitors in both mammalian and avian sera.