Chemotaxis Of Human Blood Monocytes Research Articles

FRI0002 Inhibition of chemokine receptors ccr1 and ccr6 as promising therapies for rheumatoid arthritis

BackgroundChemokines are key regulators of leukocyte activation and recruitment to sites of inflammation. Of particular relevance in rheumatoid arthritis (RA), the chemokine receptors CCR1 and CCR6 are thought to drive...

Chemotaxis of human blood monocytes toward endothelin-1 and the influence of calcium channel blockers

The adherence of monocytes to the arterial endothelium followed by its migration into the arterial intima is the earliest event in atherogenesis. The vasoconstrictive peptide, Endothelin-1 (ET-1), is elevated in patients with atherosclerosis. We were interested to know whether ET-1 was a chemoattractant for blood monocytes. Using the modified membrane filter technique for chemotaxsis assessment, ET-1 increased monocyte chemotaxis in a dose-dependent manner. Ca 2+ channel blockers, Nifedipine, Diltiazem and Verapamil (5 μM), reduced ET-1 chemotaxsis more than 60% ( P < 0.001). Aspirin and Indomethacin (1 mM and 100 μM, respectively) reduced migration by 23% ( P <0.05). α-Lipoic acid, Probucol and Neomycin (100 μM) were also migration inhibitory (37%, P<0.01). These results suggest that ET-1 is a strong chemoattractant for blood monocytes; Ca 2+ influx is probably the major stimulus for the accelerated migration induced by ET-1.

Possible chemotaxis of human monocytes by N-acetylmuramyl-L-alanyl-D-isoglutamine.

N-Acetylmuramyl-l-alanyl-d-isoglutamine (MDP) induced the chemotaxis of human blood monocytes without mediation of serum complement. Specificity (dependency on chemical structure) of the chemotactic activity of MDP was evidenced by a negligible activity of analogs lacking most of the immunomodulating activities of MDP.

Collagen-and collagen peptide-induced chemotaxis of human blood monocytes.

The ability of collagen and collagen-derived peptides to act as chemotactic stimuli was investigated by in vitro chemotaxis assays. Native human and chick skin collagen (type I) and alpha-chains obtained from purified chick skin collagen were each chemotactic for human peripheral blood monocytes. In addition, smaller peptides obtained either by digesting native collagen with bacterial collagenase or by degrading purified alpha-chains with cyanogen bromide or pepsin were also chemotactic for monocytes. In contrast, native collagen, alpha-chains, and smaller collagen-derived peptides were not chemotactic for human neutrophils. Since collagen is degraded at sites of tissue damage and inflammation, our findings suggest the possibility that such collagen-derived degradation products might directly serve as chemotactic stimuli for human peripheral blood monocytes in vivo.