Inhibition of proteolytic activity of a chlamydial proteasome/protease-like activity factor by antibodies from humans infected with Chlamydia trachomatis.
We have previously shown that individuals infected with Chlamydia trachomatis can develop a robust antibody response to a chlamydia-secreted protein (designated chlamydial proteasome/protease-like activity factor [CPAF]). We now report that sera collected from these infected individuals neutralized the proteolytic activity of CPAF. Depletion of the serum sample with CPAF proteins to remove the CPAF-specific antibodies effectively blocked the neutralization, whereas similar depletion with the HSP60 proteins failed to do so. We further demonstrated that the CPAF central region covering residues 200 to 338 was predominantly recognized by the human neutralization antibodies. The significance of the CPAF neutralization antibodies generated in chlamydia-infected individuals is discussed.
Department of Microbiology and Immunology, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Dr., San Antonio, Texas 78229, USA.
Jyotika
J
Sharma
Feng
F
Dong
Mustak
M
Pirbhai
Guangming
G
Zhong
D000907:Antibodies, Bacterial / Q000276:immunology*; D002692:Chlamydia trachomatis / Q000201:enzymology* / Q000276:immunology*; D004268:DNA-Binding Proteins / Q000378:metabolism; D006801:Humans; D046988:Proteasome Endopeptidase Complex / Q000276:immunology; D061988:Proteasome Inhibitors; D000071701:Regulatory Factor X Transcription Factors
D000907:Antibodies, Bacterial; D004268:DNA-Binding Proteins; D061988:Proteasome Inhibitors; C093524:RFX5 protein, human; D000071701:Regulatory Factor X Transcription Factors; D046988:Proteasome Endopeptidase Complex