title: High circulating autoantibodies against human oxidized low-density lipoprotein are related to stable and lower titers to unstable clinical situation.
abstract: BACKGROUND
  Oxidized lipoproteins and antibodies anti-oxidized low-density lipoprotein (anti-oxLDL) have been detected in human plasma and in atherosclerotic lesions. However, the role of these autoantibodies in the maintenance of vascular health or in the pathogenesis of acute vascular insults remains unclear. We examined the relationship of human immunoglobulin G (IgG) anti-oxLDL antibodies with cardiovascular disease risk markers in stable subjects and in patients after an acute coronary syndrome (ACS).
  
  
  METHODS
  Titers of human anti-oxLDL antibodies were measured in hypertensive subjects in primary prevention (n=94), without other risk factors, and in individuals after a recent ACS event who also had metabolic syndrome (n=116). Autoantibodies against copper ion oxidized LDL were measured by enzyme-linked-immunosorbent assay.
  
  
  RESULTS
  Anti-oxLDL titers were higher in hypertensive patients and these subjects presented lower high sensitivity C-reactive protein (hs-CRP) than those with ACS (p<0.0001). We found significant correlations between anti-oxLDL and hs-CRP (r=-0.284), body mass index (r=-0.256), waist circumference (r=-0.368), apolipoprotein B (r=-0.191), glucose (r=-0.303), systolic blood pressure (r=0.319), diastolic blood pressure (r=0.167), high-density lipoprotein cholesterol (r=0.224) and apolipoprotein A1 (r=0.257) (p<0.02 for all). After multiple linear regression hs-CRP, fasting glucose and waist circumference remained independently and inversely associated with anti-oxLDL.
  
  
  CONCLUSIONS
  Acute inflammatory and metabolic conditions decrease titers of human antibodies of IgG class against oxidized LDL, and that circulating anti-oxLDL antibodies could be associated with a protective role in atherosclerosis.
authors.affiliation: Cardiology Division, Department of Medicine, Federal University of Sao Paulo, Sao Paulo, SP, Brazil.
authors.forename: Andreza O
authors.initials: AO
authors.lastname: Santos
authors.forename: Francisco A H
authors.initials: FA
authors.lastname: Fonseca
authors.forename: Simone M
authors.initials: SM
authors.lastname: Fischer
authors.forename: Carlos M C
authors.initials: CM
authors.lastname: Monteiro
authors.forename: Sergio A B
authors.initials: SA
authors.lastname: Brandão
authors.forename: Rui M S
authors.initials: RM
authors.lastname: Póvoa
authors.forename: Maria T N
authors.initials: MT
authors.lastname: Bombig
authors.forename: Antonio C
authors.initials: AC
authors.lastname: Carvalho
authors.forename: Andréa M
authors.initials: AM
authors.lastname: Monteiro
authors.forename: Eduardo
authors.initials: E
authors.lastname: Ramos
authors.forename: Magnus
authors.initials: M
authors.lastname: Gidlund
authors.forename: Antonio M
authors.initials: AM
authors.lastname: Figueiredo Neto
authors.forename: Maria C O
authors.initials: MC
authors.lastname: Izar
mesh_terms: D054058:Acute Coronary Syndrome / Q000097:blood / Q000150:complications / Q000276:immunology; D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D001323:Autoantibodies / Q000097:blood* / Q000276:immunology*; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000378:metabolism; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000150:complications / Q000276:immunology; D016014:Linear Models; D008077:Lipoproteins, LDL / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D012307:Risk Factors
chemical_list: D001323:Autoantibodies; D015415:Biomarkers; D008077:Lipoproteins, LDL; C099252:oxidized low density lipoprotein; D002097:C-Reactive Protein