Reduced adhesion of monocyte-derived macrophages from CD36-deficient patients to type I collagen

CD36 is an 88-kDa glycoprotein expressed on platelets and monocyte/macrophages (Mphi). CD36 is a multifunctional receptor for collagen, thrombospondin, oxidized low density lipoproteins (LDL), and long-chain fatty acids. The present study was performed to investigate whether CD36 can function as an adhesion molecule which is involved in mediating human macrophages (Mphi) adhesion to type I collagen in vitro. The Mphi of human CD36-deficient as well as normal control subjects were isolated and cultured on the multi-well plates coated with type I collagen, a natural ligand for CD36. Up to 2 h of incubation, the Mphi from CD36-deficient patients showed almost a approximately 55% decrease in adhesion to type I collagen in comparison to those from controls (P < 0.01). However, there was no significant difference in the adhesion thereafter. Furthermore, the addition of antibody against CD36 into the media of control Mphi significantly inhibited the adhesion by approximately 50% (P < 0.05). The addition of oxidized LDL (OxLDL) did not alter adhesion of Mphi from both CD36-deficient and controls. These data suggest that CD36 is involved in the adhesion of Mphi to type I collagen, especially in the early stage of adhesion.