title: Detection and antigenicity of chlamydial proteins that bind eukaryotic cell membrane proteins.
abstract: Chlamydia psittaci proteins capable of binding eukaryotic cell membranes were identified and antigenically characterized. Cell membrane proteins (CMP) of noninfected cells were labeled with biotin (B-CMP), then were extracted with 1% Triton X-100. Nitrocellulose membrane strips containing sodium dodecyl sulfate-polyacrylamide gel electrophoresis-resolved proteins of chlamydial elementary bodies (EB) were reacted with the B-CMP extract, followed by addition of streptavidin-conjugated horse radish peroxidase. Among the various strains of chlamydiae examined, a protein of approximately 16 to 18 kDa consistently bound B-CMP. A second larger protein, ranging in molecular mass from 24 to 32 kDa, also bound B-CMP. Immunoblotting techniques were used to analyze the reactions of antisera from immunized and experimentally infected animals to these proteins. A rabbit polyclonal antiserum produced against the 18-kDa adhesin of a serovar-1 strain of C psittaci (B577) reacted strongly with 18-kDa proteins of all C psittaci strains, but weakly with that of C trachomatis. Mouse antisera raised against the serovar-2 (FC-Stra) 28-kDa protein reacted only with proteins of the homologous serovar. Sera from experimentally infected animals did not react with the C trachomatis 18-kDa adhesion protein, but did react in 2 patterns with related and nonrelated C psittaci isolates. Two rabbits inoculated with infective serovar-1 EB and 1 rabbit inoculated with a serovar-2 strain reacted specifically with the 18-kDa proteins of their homologous serovars. In contrast, 2 other rabbits inoculated with the same serovar-2 strain produced antisera that reacted with all C psittaci 18-kDa proteins, as did serum from a similarly inoculated bull.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Veterinary Microbiology and Parasitology, School of Veterinary Medicine, Louisiana State University, Baton Rouge 70803.
authors.forename: A
authors.initials: A
authors.lastname: Baghian
authors.forename: K L
authors.initials: KL
authors.lastname: Schnorr
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000032:analysis* / Q000378:metabolism; D001422:Bacterial Adhesion; D001426:Bacterial Proteins / Q000032:analysis* / Q000276:immunology / Q000378:metabolism; D002417:Cattle; D002460:Cell Line; D002689:Chlamydia / Q000276:immunology* / Q000378:metabolism; D002692:Chlamydia trachomatis / Q000276:immunology / Q000378:metabolism; D002691:Chlamydophila psittaci / Q000276:immunology / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D000939:Epitopes / Q000032:analysis; D005057:Eukaryotic Cells / Q000378:metabolism*; D015151:Immunoblotting; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism*; D051379:Mice; D011817:Rabbits
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D000939:Epitopes; D008565:Membrane Proteins