HIV-Infected Naïve Patients Exhibit Endothelial Dysfunction Concomitant with Decreased Natural Antibodies Against Defined Apolipoprotein B Autoantigens.

Backgorund: Traditional and HIV-defined risk factors may be associated with an increase in cardiovascular events. Recent studies have suggested that the humoral immune response to modified LDL may be associated with the process of atherosclerosis.

Objectives: To evaluate the presence of anti-oxLDL and apolipoprotein B-derived peptides in the blood, and their association with the endothelial function in HIV-infection.

Methods: This study consecutively included subjects matched for age, gender, and demographic data in two groups: (1) HIV-infected and naïve for antiviral therapy and (2) uninfected individuals. Subclinical atherosclerosis was assessed by intimal-media thickness, using ultrasonography of the carotid arteries. Endothelial function was determined by flow-mediated dilatation (FMD) of the brachial artery by ultrasonography. Autoantibodies (IgM, IgG) anti-oxidized low-density lipoprotein (oxLDL), anti-apolipoprotein B-peptide fragments (ApoB-D and 0033G-Cys peptides), and cytokine levels were evaluated by ELISA.

Results: This study's results showed no difference in subclinical atherosclerosis between groups; however, HIV-infected subjects showed a lower FMD, when compared to non-infected subjects. Therefore, HIV-infected subjects showed higher levels of inflammatory cytokines, titers of IgG anti-oxLDL, and IgG anti-ApoB-D. In contrast, titers of IgM anti-ApoB-D were lower in HIV-infected individuals and associated with reduced endothelial functions.

Conclusions: This study's results show that HIV infection, in naïve subjects, is associated with endothelial dysfunction and a decline of natural antibodies to apo-B antigens.