Reduced Adhesion of Monocyte-Derived Macrophages from CD36-Deficient Patients to Type I Collagen

Abstract

CD36 is an 88-kDa glycoprotein expressed on platelets and monocyte/macrophages (Mφ). 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 (Mφ) adhesion to type I collagen in vitro. The Mφ 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 Mφ from CD36-deficient patients showed almost a ∼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 Mφ significantly inhibited the adhesion by ∼50% (P < 0.05). The addition of oxidized LDL (OxLDL) did not alter adhesion of Mφ from both CD36-deficient and controls. These data suggest that CD36 is involved in the adhesion of Mφ to type I collagen, especially in the early stage of adhesion.