Short- and long-term elevation of autoantibody titers against oxidized LDL in patients with acute coronary syndromes. Role of the lipoprotein-associated phospholipase A2 and the effect of atorvastatin treatment

Atherosclerosis. 2008 Jan;196(1):289-297. doi: 10.1016/j.atherosclerosis.2006.10.033. Epub 2006 Nov 30.

Abstract

Oxidized low-density lipoprotein (oxLDL) is immunogenic while oxidized phospholipids (oxPL) formed on oxLDL and lysophosphatidylcholine (lyso-PC) generated during LDL oxidation through the hydrolysis of oxPL by the lipoprotein-associated phospholipase A(2) (Lp-PLA(2)), significantly contribute to oxLDL immunogenicity. We determined the autoantibody titers against various forms of mildly oxLDL in patients with acute coronary syndromes without persistent elevation of the ST segment (NSTE-ACS) and with undetectable serum levels of lipoprotein (a). Moreover, the effect of early atorvastatin administration on these autoantibody titers was evaluated. From the 133 consecutive NSTE-ACS patients, 55 were eligible for the study. Thirty-four received atorvastatin (group A), whereas 21 did not received any hypolipidemic therapy (group B). Two forms of copper-oxidized LDL were prepared at the end of propagation or decomposition phase (oxLDL(P) or oxLDL(D), respectively). Similar types of oxLDL were prepared after previous inactivation of the endogenous Lp-PLA(2) [oxLDL(-)]. In group B, autoantibody titers of IgG class against oxLDL(P) and oxLDL(D) were elevated at 1 month of follow-up to reach the baseline values 3 months afterwards. By contrast the titers against oxLDL(-)(P) and oxLDL(-)(D) increased at 1 month of follow-up and remained elevated for up to 6 months of follow-up. Atorvastatin treatment prevented the elevation of autoantibody titers against all forms of oxidized LDL. We conclude that a short-term immune response against oxLDL(P) and oxLDL(D) (enriched in lyso-PC) and a chronic immune response against oxLDL(-)(P) and oxLDL(-)(D) (enriched in oxPL) are observed after an NSTE-ACS, suggesting an important role of the LDL-associated Lp-PLA(2) in modulating these immune responses. Early atorvastatin treatment prevents both immune responses; however, the clinical significance of this effect remains to be established.

Publication types

  • Clinical Trial

MeSH terms

  • 1-Alkyl-2-acetylglycerophosphocholine Esterase / drug effects
  • Acute Coronary Syndrome / blood
  • Acute Coronary Syndrome / immunology*
  • Aged
  • Atorvastatin
  • Autoantibodies / drug effects*
  • Female
  • Heptanoic Acids / pharmacology*
  • Humans
  • Hydroxymethylglutaryl-CoA Reductase Inhibitors / pharmacology*
  • Immunoglobulin G / drug effects*
  • Lipoproteins, LDL / immunology*
  • Male
  • Middle Aged
  • Pyrroles / pharmacology*

Substances

  • Autoantibodies
  • Heptanoic Acids
  • Hydroxymethylglutaryl-CoA Reductase Inhibitors
  • Immunoglobulin G
  • Lipoproteins, LDL
  • Pyrroles
  • oxidized low density lipoprotein
  • Atorvastatin
  • 1-Alkyl-2-acetylglycerophosphocholine Esterase