%0 Journal Article
%T Evolution of the Macrophage CD163 Phenotype and Cytokine Profiles in a Human Model of Resolving Inflammation
%A Betsy J. Evans
%A Dorian O. Haskard
%A Gregory Sempowksi
%A R. Clive Landis
%J International Journal of Inflammation
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/780502
%X Cantharidin skin blisters were examined over two days to model the acute and resolving phases of inflammation in human skin. Four blisters were created by topical administration of cantharidin (0.1% v/v) to the forearm of healthy volunteers, with IRB approval. Duplicate skin blisters were aspirated at 16 and 40 hours to model the proinflammatory and resolving phases, respectively. There was a significant increase in leukocyte infiltrate at 40£¿h with appearance of a ¡°resolving macrophage¡± phenotype CD14+CD163+ by flow cytometry. Neutrophils acquired apoptotic markers at 40£¿h and were observed to be phagocytosed by macrophagic ¡°Reiter¡¯s¡± cells. Multiplex cytokine analysis demonstrated that monocyte chemoattractant protein (MCP-1/CCL2), interleukin- (IL-) 6, IL-8/CXCL8, macrophage inflammatory protein (MIP1¦Á/CCL3), MIP-1¦Â/CCL4, tumor necrosis factor- (TNF-) ¦Á, and eotaxin (CCL11) were all significantly upregulated at 16£¿h compared with 40£¿h. In contrast, immunoregulatory transforming growth factor- (TGF-) ¦Â, macrophage-derived chemokine (MDC/CCL22), and interferon-inducible protein (IP-10/CXCL10) were significantly elevated at 40£¿h. Our results demonstrate that the phases of inflammation and resolution can be discriminated in a two-day model of dermal wound healing. This confirms and extends our understanding of wound repair in humans and provides a powerful research tool for use in clinical settings and to track the molecular benefits of therapeutic intervention. 1. Introduction The wound healing process is balanced between an early cytodestructive inflammatory phase and a subsequent resolving phase supporting tissue regeneration [1, 2]. Cells of the monocyte/macrophage lineage have been recognized since the 1970s to participate actively in both of these phases [3]. A key switching point is the conversion of the proinflammatory monocyte into a macrophage phenotype capable of dampening the inflammatory response and moulding fibrosis [4, 5]. The prototypic marker of this conversion is CD163 (the haemoglobin scavenger receptor), first recognised as the ¡°resolving macrophage marker¡± in humans and as the ED2 antigen in rats [6, 7]. CD163 plays an everyday role in neutralising pro-oxidant free heme released during hemolysis in bruising or tissue injury. In a rat model of lung injury, it was expressed during inflammatory resolution at which macrophages engulfed apoptotic neutrophils [8]. In a model of gout involving monosodium urate crystal phagocytosis, the CD163+ phenotype evolves at the stage when monocytes/macrophages switch production from proinflammatory
%U http://www.hindawi.com/journals/iji/2013/780502/