Circulating Microparticles Are Elevated in Treated HIV‐1 Infection and Are Deleterious to Endothelial Cell Function

Background Circulating microparticles have emerged as biomarkers and effectors of vascular disease. Elevated rates of cardiovascular disease are seen in HIV‐1–seropositive individuals. The aims of this study were to determine: (1) if circulating microparticles are elevated in antiretroviral therapy–treated HIV‐1–seropositive adults; and (2) the effects of microparticles isolated from antiretroviral therapy–treated HIV‐1–seropositive adults on endothelial cell function, in vitro. Methods and Results Circulating levels of endothelial‐, platelet‐, monocyte‐, and leukocyte‐derived microparticles were determined by flow cytometry in plasma from 15 healthy and 15 antiretroviral therapy–treated, virologically suppressed HIV‐1–seropositive men. Human umbilical vein endothelial cells were treated with microparticles from individual subjects for 24 hours; thereafter, endothelial cell inflammation, oxidative stress, senescence, and apoptosis were assessed. Circulating concentrations of endothelial‐, platelet‐, monoc...