Down regulation of CD11b and CD18 expression in children with hypercholesterolemia: A preliminary report.

BACKGROUND AND AIM: Cell adhesion molecules play an important role in the development of atherosclerosis mediating the attachment of monocytes to the endothelium. The aim of our study was to assess the cell surface expression of CD11b/CD18 integrin on the phagocytes of children affected by hypercholesterolemia. METHODS AND RESULTS: Twenty-six children with hypercholesterolemia (15 males, mean age 8.3, range 2-18) with a family history of early cardiovascular disease, as well as 26 children with normocholesterolemia matched for gender and age (15 males, mean age 8.3) were studied. Cell surface expression of CD11b/CD18 on peripheral blood mononuclear cells (PBMC) were analyzed by flow cytometry. The geometric mean percentages of CD11b and CD18 expression were significantly lower in the hypercholesterolemic group [52 (95% confidence intervals, 40-68) and 88 (84-93)] than in the control group [87 (83-91), P<0.0001 and 93 (89-96), P<0.05], respectively. After correction for age, gender, and pubertal status, CD11b cell surface expression on PBMC was inversely and independently correlated with total cholesterol concentrations (r=-0.395; P<0.01) and LDL (r=-0.307; P<0.05), as well as with triglycerides (r=-0.406; P<0.01). CONCLUSIONS: In children with hypercholesterolemia, cell surface expression of CD11b and CD18 on PBMC was significantly decreased. Follow-up studies are necessary to determine the clinical implications of these findings in the context of the natural course and progression of atherosclerosis in high risk children.