Antigenic analysis of avian Chlamydia psittaci using monoclonal antibodies to the major outer membrane protein.

Monoclonal antibodies to the major outer membrane protein (MOMP) of Chlamydia psittaci derived from a parrot were established for antigenic analysis of avian C. psittaci. With 17 monoclonal antibodies to MOMP, 17 reactivity patterns were identified on 112 strains of C. psittaci, C. pneumoniae and C. trachomatis, which were isolated from birds, mammals and humans in Japan, U.S.A., Canada and Taiwan, from 1938 to 1987. Immunological reactivity of budgerigar-derived strains to the monoclonal antibodies was different from that of pigeon-derived strains. Imported bird-derived strains were distinguishable from domestic bird-derived strains by the reactivity to the monoclonal antibodies. A close relationship between the subtypes and geographic origins was indicated on budgerigar-derived strains. On the contrary, various reactivity patterns were shown in pigeon-derived strains isolated in a narrow area. The monoclonal antibodies established in the present work may be useful probes for ecological study of avian C. psittaci.