Submitted to: Journal of Veterinary Diagnostic Investigation
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/29/1996
Publication Date: N/A
Interpretive Summary: Chlamydia psittaci is a bacterium that can cause severe disease and death in birds and many other animals. A number of distinct strains were known to produce disease in birds. Five isolates were recovered that were serologically different than the previously recognized serovars. These isolates were tested using genetic engineering techniques and determined to orepresent 2 new strains. Monoclonal antibodies were produced to 2 of the isolates. The monoclonal antibodies, along with genetic engineering testing of the major outer membrane protein gene of the isolates, were used to prove that the isolates represented 2 new serovars from birds. These represent the 5th and 6th strains of Chlamydia psittaci found in North American birds. Knowing what strains occur in birds is important for vaccine development, as little cross-protection occurs between strains.
Technical Abstract: Five C. psittaci isolates (turkey, psittacine, human, and 2 pigeon isolates) failed to react with our serovar-specific monoclonal antibodies (MAbs) to known avian and mammalian C. psittaci serovars and were presumed to represent one or more new serovars. The isolates were characterized using restriction endonuclease analysis (REA) of the whole genome, PCR-RFLP Pof the MOMP genome, MAb comparisons, and growth in tissue culture. MAbs were produced to the human isolate (MP) and to the VS225 (psittacine) isolate. The MAB results show that the isolates represent 2 new avian serovars (serovar E and serovar F, respectively). PCR-RFLP of the MOMP genome demonstrated that the isolates are distinct. The whole genome REA data and the growth patterns in tissue culture indicate that the new serovars are similar to earlier recognized avian serovars. A sub-species MAB that reacted with serovar A and serovar B also reacted with serovar E, indicating that these serovars are closely related. The results prove tha these isolates represent 2 new avian serovars, making them the fifth and sixth avian serovars identified in North American birds.