Stress-induced changes in the expression of monocytic β₂-integrins: The impact of arousal of negative affect and adrenergic responses to the Anger Recall Interview

Adhesion of circulating monocytes to the vascular endothelium is one of the earliest steps in the development of atherosclerosis. This leukocyte-to-endothelium interaction is mediated in part by β₂-integrins, a group of cell adhesion molecules that bind to endothelial ligands. Given the significance of this interaction to atherogenesis, we examined the effects of stress, operationalized as the arousal of negative affect (NA) and cardiovascular and catecholamine responses to the Anger Recall Interview (ARI), on the expression of LFA-1 (CD11a), Mac-1 (CD11b) and p150/95 (CD11c) on circulating monocytes (CD14+). Subjects were 173 healthy, nonsmoking men and women (60% men, 40% minorities, aged 18-49 year). Arousal of NA, cardiovascular responses (heart rate [HR], systolic blood pressure [SBP], diastolic blood pressure [DBP]), circulating catecholamines (epinephrine [Epi], norepinephrine [Ne]) and β₂-integrin (CD11/CD18) expression were determined prior to and following the ARI. The principal findings were that the ARI, on average, induced a decrease in monocyte expression of β₂-integrins. However, after adjusting for age, sex, body mass index, exercise status, and baseline level of β₂-integrin expression, those individuals who showed the largest increases in NA, Ne and DBP during the ARI showed an increase in monocyte β₂-integrin expression. Thus, heightened psychological and physiological stress responses induced phenotypic changes in monocytic expression of β₂-integrins that are consistent with the role of monocytes/macrophages in vascular inflammation and increased risk of atherosclerotic cardiovascular disease.