Autoantibody response to chromatographic fractions from oxidized LDL in unstable angina patients and healthy controls

Levels of autoantibodies to oxidized low-density lipoprotein (oxLDL) have been correlated to atherosclerosis; however, contradictory results have been shown. To better understand the role of autoantibodies to oxLDL in atherogenesis, and their potential to predict risk of developing coronary artery disease we investigated the antibody response of unstable angina (UA) patients and healthy controls against chromatographic separated fractions of oxLDL. Five major peaks were detected after chromatographic separation of oxLDL and 10 fractions were collected. Surprisingly, when the response to high molecular weight fractions was analysed, we observed a significant increase in the levels of autoantibodies in controls compared to UA. In contrast, when the autoantibody response to intermediate and low molecular weight fractions was analysed, we observed that the UA group showed consistently higher levels compared with controls. Our data demonstrates that within oxLDL there are major fractions that can be recognized by autoantibodies from either UA patients or healthy individuals, and that the use of total oxLDL as an antigen pool may mask the presence of some antigenic molecules and their corresponding antibodies. Further studies are needed, but the analysis of antibody profiles may indeed open up a novel approach for evaluation and prevention against atherosclerosis.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundacao Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Laboratórios de Investigação Médica (LIM - HCFMUSP)Universidade de São Paulo - Laboratorio de Investigacao Medica 38 (LIM 38) - FM/USPConselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Instituto do Milenio de Fluidos ComplexosInstituto do Milenio de Fluidos ComplexosInstitute of Cardiology Dante PazzaneseInstitute of Cardiology Dante Pazzanes