title: P2Y(6) agonist uridine 5'-diphosphate promotes host defense against bacterial infection via monocyte chemoattractant protein-1-mediated monocytes/macrophages recruitment.
abstract: Extracellular nucleotides are important messengers involved in series crucial physiological functions through the activation of P2 purinergic receptors. The detailed function and mechanism of the P2Y family in regulating immune response against invaded pathogens still remains unknown. In this study, the activation of purinoreceptor P2Y(6) by UDP was found to play a crucial role in promoting host defense against invaded bacteria through monocytes/macrophages recruitment. The expression level of P2Y(6) was much higher than other purinoreceptors in RAW264.7 cells, bone marrow macrophages, and peritoneal macrophages determined by real-time PCR. The supernatant of UDP (P2Y(6)-specific agonist)-treated RAW264.7 cells exhibited direct chemotaxis to monocytes/macrophages in vitro through Boyden Chambers assay. Meanwhile, the releasing of MCP-1 (MCP-1/CCL2) was enhanced obviously by UDP both in mRNA and protein level. Furthermore, the activation of P2Y(6) receptor by UDP also promotes ERK phosphorylation and AP-1 activation in a concentration- and time-dependent manner in RAW264.7 cells. This UDP-induced activation could be inhibited by P2Y(6) selectivity antagonist (MRS2578), MEK inhibitor (U0126), and MCP-1 blocking Ab, respectively. Moreover, i.p. injection with UDP resulted in a more efficacious clearance of invaded Escherichia coli and lower mortality in peritonitis mouse model. Together, our studies demonstrate that P2Y(6) receptor could be a novel mediator in upregulating innate immune response against the invaded pathogens through recruiting monocytes/macrophages.
authors: Institute of Biomedical Sciences, School of Life Sciences, East China Normal University, Shanghai 200062, People's Republic of China.
authors: Zhi
authors: Z
authors: Zhang
authors: Ziqiang
authors: Z
authors: Wang
authors: Hua
authors: H
authors: Ren
authors: Miaomiao
authors: M
authors: Yue
authors: Kan
authors: K
authors: Huang
authors: Hongjie
authors: H
authors: Gu
authors: Mingyao
authors: M
authors: Liu
authors: Bing
authors: B
authors: Du
authors: Min
authors: M
authors: Qian
mesh_terms: D000818:Animals; D001424:Bacterial Infections / Q000276:immunology* / Q000378:metabolism; D015153:Blotting, Western; D018932:Chemokine CCL2 / Q000276:immunology*; D002634:Chemotaxis, Leukocyte / Q000276:immunology; D024202:Electrophoretic Mobility Shift Assay; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D008262:Macrophage Activation / Q000276:immunology; D008264:Macrophages / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D009000:Monocytes / Q000276:immunology*; D058910:Purinergic P2 Receptor Agonists / Q000276:immunology* / Q000378:metabolism; D018048:Receptors, Purinergic P2 / Q000276:immunology* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000276:immunology; D014530:Uridine Diphosphate / Q000276:immunology* / Q000378:metabolism
chemical_list: C491768:Ccl2 protein, mouse; D018932:Chemokine CCL2; D058910:Purinergic P2 Receptor Agonists; D018048:Receptors, Purinergic P2; C099845:purinoceptor P2Y6; D014530:Uridine Diphosphate