Monocytes and oxidative stress are central in atherosclerosis. Monocyte attachment to laminin-1 derived from either healthy volunteers or patients with diabetes mellitus type II has been evaluated by three different assays: the myeloperoxidase assay, Hemacolor kit, and crystal violet staining. Monocytes derived from diabetic patients showed an increased ability to attach to native laminin-1 as compared with controls. In addition, monocytes derived from both healthy donors and diabetics attached at a higher degree to laminin-1 carbonylated by methylglyoxal in comparison with the native molecule. The results indicate an increased interaction between monocytes and laminin-1 in the case that the protein is carbonylated.