title: The Wingless homolog Wnt5a stimulates phagocytosis but not bacterial killing.
abstract: Phagocytosis is a primary defense program orchestrated by monocytes/macrophages. Unregulated phagocytosis can lead to pathological conditions. In the current study we have demonstrated that Wnt5a stimulates phagocytosis through PI3 kinase-Rac1 and lipid-raft-dependent processes. Wnt5a-mediated augmentation in phagocytosis is suppressed by blocking expression of the putative Wnt5a receptor Frizzled 5. Enhanced phagocytosis of bacteria by Wnt5a-Fz5 signaling increases the secretion of proinflammatory cytokines, but not the bacterial killing rate. Furthermore, a small molecule inhibitor of Wnt production, IWP-2, which reduces secretion of functionally active Wnt5a, not only suppresses both phagocytosis and the secretion of proinflammatory cytokines but also accelerates the bacterial killing rate.
authors.affiliation: Division of Cancer Biology and Inflammatory Disorder, Indian Institute of Chemical Biology, Jadavpur, Kolkata, India.
authors.forename: George
authors.initials: G
authors.lastname: Maiti
authors.forename: Debdut
authors.initials: D
authors.lastname: Naskar
authors.forename: Malini
authors.initials: M
authors.lastname: Sen
mesh_terms: D000818:Animals; D002460:Cell Line; D016207:Cytokines / Q000276:immunology / Q000378:metabolism; D004926:Escherichia coli / Q000276:immunology* / Q000502:physiology; D004927:Escherichia coli Infections / Q000276:immunology* / Q000378:metabolism / Q000382:microbiology; D051157:Frizzled Receptors / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D054884:Host-Pathogen Interactions / Q000276:immunology; D015151:Immunoblotting; D018836:Inflammation Mediators / Q000276:immunology / Q000378:metabolism; D007739:L Cells; D008264:Macrophages / Q000276:immunology / Q000378:metabolism / Q000382:microbiology; D021962:Membrane Microdomains / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D018613:Microscopy, Confocal; D009479:Neuropeptides / Q000378:metabolism; D010587:Phagocytosis / Q000276:immunology*; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D034622:RNA Interference; D015398:Signal Transduction / Q000276:immunology; D051153:Wnt Proteins / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D000071818:Wnt-5a Protein; D020744:rac GTP-Binding Proteins / Q000378:metabolism; D020830:rac1 GTP-Binding Protein
chemical_list: D016207:Cytokines; D051157:Frizzled Receptors; D018836:Inflammation Mediators; D009479:Neuropeptides; D019869:Phosphatidylinositol 3-Kinases; D051153:Wnt Proteins; D000071818:Wnt-5a Protein; D020744:rac GTP-Binding Proteins; D020830:rac1 GTP-Binding Protein; C403211:Fzd5 protein, mouse; C484602:Rac1 protein, mouse; C438615:Wnt5a protein, mouse