Human monocyte characteristics are altered in hypercholesterolaemia.
Peripheral blood monocytes are involved during atherogenesis in adhering to endothelium, migrating into the subendothelial space and taking-up lipoproteins to become macrophage/foam cells. We have assessed whether peripheral blood monocyte characteristics are altered in human hyperlipidaemia in age/sex/smoking status matched pairs of patients and controls. Monocytes from the hypercholesterolaemic patients, as opposed to the controls, were more sensitive to stimulation by the agonist, N-formyl-methionyl-leucyl-phenylalanine, with respect to chemokinesis (stimulation index 1.48 +/- 0.17 vs. 1.10 +/- 0.14), chemotaxis (4.05 +/- 0.55 vs. 2.72 +/- 0.24) and adhesion to porcine aortic endothelial monolayers (1.26 +/- 0.05 vs. 1.17 +/- 0.06). The patients' monocyte total surface expression of the adhesion glycoprotein CD11b/CD18 (37.5 +/- 7.1 vs. 36.0 +/- 7.1), but not CD11c/CD18 (31.6 +/- 7.2 vs. 31.4 +/- 6.8), was increased; however, the monocytes in hyperlipidaemia were larger (9.15 +/- 0.11 microns vs. 8.98 +/- 0.11 microns) such that the surface density of CD11b/CD18 was not altered (0.144 +/- 0.029 vs. 0.142 +/- 0.029). The data suggest that circulating monocytes are functionally different in hypercholesterolaemia. This may explain the increased involvement by monocytes in hypercholesterolaemia-related atherogenesis.
Bath
P M
PM
Department of Medicine, King's College School of Medicine and Dentistry, London, U.K.
Gladwin
A M
AM
Martin
J F
JF
D000818:Animals; D002448:Cell Adhesion; D002465:Cell Movement; D002478:Cells, Cultured; D002634:Chemotaxis, Leukocyte; D004730:Endothelium, Vascular / Q000502:physiology; D006801:Humans; D006937:Hypercholesterolemia / Q000097:blood*; D008562:Membrane Glycoproteins / Q000032:analysis; D008875:Middle Aged; D009000:Monocytes / Q000378:metabolism / Q000502:physiology*; D010969:Plastics; D013552:Swine
D008562:Membrane Glycoproteins; D010969:Plastics