title: Prostaglandin E2 promotes degranulation-independent release of MCP-1 from mast cells.
abstract: Mast cells (MCs) are common components of inflammatory infiltrates and a source of proangiogenic factors. Inflammation is often accompanied by vascular changes. However, little is known about modulation of MC-derived proangiogenic factors during inflammation. In this study, we evaluated the effects of the proinflammatory mediator prostaglandin E2 (PGE2) on MC expression and release of proangiogenic factors. We report that PGE2 dose-dependently induces primary MCs to release the proangiogenic chemokine monocyte chemoattractant protein-1 (MCP-1). This release of MCP-1 is complete by 2 h after PGE2 exposure, reaches levels of MCP-1 at least 15-fold higher than background, and is not accompanied by degranulation or increased MCP-1 gene expression. By immunoelectron microscopy, MCP-1 is detected within MCs at a cytoplasmic location distinct from the secretory granules. Dexamethasone and cyclosporine A inhibit PGE2-induced MCP-1 secretion by approximately 60%. Agonists of PGE2 receptor subtypes revealed that the EP1 and EP3 receptors can independently mediate MCP-1 release from MCs. These observations identify PGE2-induced MCP-1 release from MCs as a pathway underlying inflammation-associated angiogenesis and extend current understanding of the activities of PGE2.
authors.affiliation: Experimental Transplantation and Immunology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland 20892, USA. Nakayamt@mail.nih.gov
authors.forename: Takayuki
authors.initials: T
authors.lastname: Nakayama
authors.forename: Noriko
authors.initials: N
authors.lastname: Mutsuga
authors.forename: Lei
authors.initials: L
authors.lastname: Yao
authors.forename: Giovanna
authors.initials: G
authors.lastname: Tosato
mesh_terms: D043925:Angiogenesis Inducing Agents / Q000276:immunology / Q000378:metabolism*; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology; D015550:Cell Degranulation / Q000187:drug effects* / Q000276:immunology; D002478:Cells, Cultured; D018932:Chemokine CCL2 / Q000276:immunology / Q000378:metabolism*; D016572:Cyclosporine / Q000494:pharmacology; D003907:Dexamethasone / Q000494:pharmacology; D015232:Dinoprostone / Q000276:immunology / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004336:Drug Antagonism; D007166:Immunosuppressive Agents / Q000494:pharmacology; D007249:Inflammation / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D008407:Mast Cells / Q000276:immunology / Q000378:metabolism* / Q000648:ultrastructure; D051379:Mice; D009389:Neovascularization, Pathologic / Q000276:immunology / Q000473:pathology; D010120:Oxytocics / Q000276:immunology / Q000494:pharmacology*; D022142:Secretory Vesicles / Q000276:immunology / Q000378:metabolism / Q000648:ultrastructure
chemical_list: D043925:Angiogenesis Inducing Agents; D000893:Anti-Inflammatory Agents; C491768:Ccl2 protein, mouse; D018932:Chemokine CCL2; D007166:Immunosuppressive Agents; D010120:Oxytocics; D003907:Dexamethasone; D016572:Cyclosporine; D015232:Dinoprostone