Activación de polimorfonucleares neutrófilos por UDPGlucosa extracelular

Abstract

Extracellular purinergic nucleotides play important roles in cell signalling by activating their specific receptors expressed in most cells. The P2Y14 receptor responds to extracellular signalling by UDP-glucose but not to other free purinergic nucleotides / nucleosides. Normal polymorphonuclear neutrophils have high levels of P2Y14-R transcripts. However, the function of these receptors in these cells has been poorly investigated. The aim of this study was to demonstrate whether UDP-glucose induces chemotaxis and adhesion of neutrophils. For this purpose, we measured chemotaxis in: a) polymorphonuclear neutrophils of patients with leukocytosis and neutrophilia (n=10); b) polymorphonuclear neutrophils of healthy individuals (n=10); c) normal polymorphonuclear neutrophils pre-incubated with serum from normal individuals (n = 20); and d) normal polymorphonuclear neutrophils pre-incubated with serum from patients with rheumatoid arthritis (n=17). The baseline control was performed with polymorphonuclear neutrophils pre-incubated with RPMI. The adhesiveness to glass of polymorphonuclear neutrophils was also tested. UDP-glucose and fMLP were used as agonists in both procedures. In a and b, the values of chemotaxis induced with fMLP were similar, whereas those induced with UDP-glucose were higher in group a. In group c, fMLP showed greater stimulation than UDP-glucose, whereas in group d chemotaxis was similar with both agonists. UDP-glucose showed higher chemotactic activity in cells pre-incubated with serum from patients with rheumatoid artritis than in cells pre-incubated with normal serum. Adhesiveness to glass of normal neutrophils was higher when induced with UDP-glucose than when induced with fMLP.