title: The Protectin PCTR1 Is Produced by Human M2 Macrophages and Enhances Resolution of Infectious Inflammation.
abstract: Inflammation and its natural resolution are host-protective responses triggered by infection or injury. The resolution phase of inflammation is regulated by enzymatically produced specialized pro-resolving mediators. We recently identified a new class of peptide-conjugated specialized pro-resolving mediators that carry potent tissue regenerative actions that belong to the protectin family and are coined protectin conjugates in tissue regeneration (PCTR). Herein, with the use of microbial-induced peritonitis in mice and liquid chromatography-tandem mass spectrometry-based lipid mediator metabololipidomics, we found that PCTR1 is temporally regulated during self-resolving infection. When administered at peak of inflammation, PCTR1 enhanced macrophage recruitment and phagocytosis of Escherichia coli, decreased polymorphonuclear leukocyte infiltration, and counter-regulated inflammation-initiating lipid mediators, including prostaglandins. In addition, biologically produced PCTR1 promoted human monocyte and macrophage migration in a dose-dependent manner (0.001 to 10.0 nmol/L). We prepared PCTR1 via organic synthesis and confirmed that synthetic PCTR1 increased macrophage and monocyte migration, enhanced macrophage efferocytosis, and accelerated tissue regeneration in planaria. With human macrophage subsets, PCTR1 levels were significantly higher in M2 macrophages than in M1 phenotype, along with members of the resolvin conjugates in tissue regeneration and maresin conjugate families. In contrast, M1 macrophages gave higher levels of cysteinyl leukotrienes. Together, these results demonstrate that PCTR1 is a potent monocyte/macrophage agonist, regulating key anti-inflammatory and pro-resolving processes during bacterial infection.
authors.affiliation: Center for Experimental Therapeutics and Reperfusion Injury, Harvard Institutes of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Sesquile
authors.initials: S
authors.lastname: Ramon
authors.affiliation: Center for Experimental Therapeutics and Reperfusion Injury, Harvard Institutes of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Jesmond
authors.initials: J
authors.lastname: Dalli
authors.affiliation: Center for Experimental Therapeutics and Reperfusion Injury, Harvard Institutes of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Julia M
authors.initials: JM
authors.lastname: Sanger
authors.affiliation: Center for Experimental Therapeutics and Reperfusion Injury, Harvard Institutes of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Jeremy W
authors.initials: JW
authors.lastname: Winkler
authors.affiliation: Department of Pharmaceutical Chemistry, University of Oslo, Oslo, Norway.
authors.forename: Marius
authors.initials: M
authors.lastname: Aursnes
authors.affiliation: Department of Pharmaceutical Chemistry, University of Oslo, Oslo, Norway.
authors.forename: Jørn E
authors.initials: JE
authors.lastname: Tungen
authors.affiliation: Department of Pharmaceutical Chemistry, University of Oslo, Oslo, Norway.
authors.forename: Trond V
authors.initials: TV
authors.lastname: Hansen
authors.affiliation: Center for Experimental Therapeutics and Reperfusion Injury, Harvard Institutes of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts. Electronic address: cnserhan@zeus.bwh.harvard.edu.
authors.forename: Charles N
authors.initials: CN
authors.lastname: Serhan
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D004281:Docosahexaenoic Acids / Q000494:pharmacology; D004926:Escherichia coli / Q000187:drug effects; D004927:Escherichia coli Infections / Q000382:microbiology*; D006801:Humans; D007249:Inflammation / Q000188:drug therapy; D008264:Macrophages / Q000166:cytology*; D008297:Male; D051379:Mice; D009000:Monocytes / Q000187:drug effects*; D010587:Phagocytosis / Q000187:drug effects / Q000502:physiology*
chemical_list: D004281:Docosahexaenoic Acids