Association of serum antibodies to heat-shock protein 65 with coronary calcification levels: suggestion of pathogen-triggered autoimmunity in early atherosclerosis.
BACKGROUND
Previous studies demonstrated an association between antibodies to mycobacterial heat-shock protein 65 (mHSP65) and carotid artery thickening. We examined whether mHSP65 antibodies are associated with levels of coronary calcification that appear to reflect preclinical coronary artery disease (CAD).


RESULTS
Serum specimens from 201 healthy asymptomatic subjects (52% male; mean age, 56.6 years) undergoing electron-beam computed tomographic imaging were used to measure levels of mHSP65 and human HSP60 antibodies and antibodies to several infectious pathogens. We found that 84% of the study subjects had anti-mHSP65 IgG antibodies. Mean titers of mHSP65 antibodies were higher (1:394 versus 1:267, P=0.012) in individuals with than in those without elevated levels of coronary calcium (calcium score > or =150). Increasing titers of mHSP65 antibodies were significantly associated, in a dose-response manner, with elevated levels of coronary calcification. Individuals with the highest titers of mHSP65 antibodies (> or =1:800) had an adjusted odds ratio (OR) of 14.3 for having elevated coronary calcium (P=0.004). Association of mHSP65 antibodies with elevated coronary calcification levels was independent of CAD risk factors after multivariate adjustment (P=0.037). Interestingly, mHSP65 antibody titers were correlated with Helicobacter pylori infection (P=0.004), which maintained significance after adjustment for CAD risk factors and seropositivities to other pathogens (adjusted OR, 3.1; 95% CI, 1.4 to 6.6). No association was found between antibodies to human HSP60 and levels of coronary calcification.


CONCLUSIONS
Antibodies to mHSP65 are associated with elevated levels of coronary calcification and correlated with H pylori infection, suggesting that pathogen-triggered autoimmunity plays a role in early atherosclerosis.
Zhu
Jianhui
J
Cardiovascular Research Institute, Washington Hospital Center, 108 Irving St, NW, GHRB Room 217, Washington, DC 20010, USA. jianhui.zhu@medstar.net
Katz
Richard J
RJ
Quyyumi
Arshed A
AA
Canos
Daniel A
DA
Rott
David
D
Csako
Gyorgy
G
Zalles-Ganley
Alexandra
A
Ogunmakinwa
Jibike
J
Wasserman
Alan G
AG
Epstein
Stephen E
SE
D000328:Adult; D000368:Aged; D000907:Antibodies, Bacterial / Q000097:blood*; D001323:Autoantibodies / Q000097:blood; D015551:Autoimmunity; D001426:Bacterial Proteins / Q000276:immunology*; D002114:Calcinosis / Q000276:immunology* / Q000382:microbiology; D018834:Chaperonin 60 / Q000276:immunology; D018833:Chaperonins / Q000276:immunology*; D003324:Coronary Artery Disease / Q000276:immunology* / Q000382:microbiology / Q000473:pathology; D005260:Female; D016481:Helicobacter Infections / Q000150:complications / Q000276:immunology; D016480:Helicobacter pylori; D006801:Humans; D007239:Infections / Q000276:immunology; D008297:Male; D008875:Middle Aged; D012307:Risk Factors
D000907:Antibodies, Bacterial; D001323:Autoantibodies; D001426:Bacterial Proteins; D018834:Chaperonin 60; C074119:heat-shock protein 65, Mycobacterium; D018833:Chaperonins