Journal
JOURNAL OF PATHOLOGY
Volume 205, Issue 1, Pages 102-111Publisher
WILEY
DOI: 10.1002/path.1690
Keywords
mast cell; infarction; myocardial ischaemia/reperfusion; macrophage; chemokine; tryptase; chymase; inflammation
Funding
- NATIONAL HEART, LUNG, AND BLOOD INSTITUTE [P01HL024136, P01HL042550] Funding Source: NIH RePORTER
- NHLBI NIH HHS [P01 HL024136-250014, P01 HL024136-25, P01 HL024136-240014, P01 HL024136-260002, P01 HL024136-24, P01 HL024136-23, P01 HL042550, P01 HL024136-26, HL-42550, P01 HL024136-230014, P01 HL024136] Funding Source: Medline
Ask authors/readers for more resources
Mast cells and macrophages infiltrate healing myocardial infarcts and may play an important role in regulating fibrous tissue deposition and extracellullar matrix remodelling. This study examined the time-course of macrophage and mast cell accumulation in healing infarcts and studied the histological characteristics and protease expression profile of mast cells in a canine model of experimental infarction. Although macrophages were more numerous than mast cells in infarct granulation tissue, macrophage density decreased during maturation of the scar, whereas mast cell numbers remained persistently elevated. During the inflammatory phase of infarction, newly recruited leucocytes infiltrated the injured myocardium and appeared to be clustered in close proximity to degranulating cardiac mast cells. During the proliferative phase of healing, mast cells had decreased granular content and were localized close to infarct neovessels. In contrast, macrophages showed no selective localization. Mast cells in healing canine infarcts were alcian blue/safranin-positive cells that expressed both tryptase and chymase. In order to explain the pro-inflammatory and angiogenic actions of tryptase - the major secretory protein of mast cells - its effects on endothelial chemokine expression were examined. Chemokines are chernotactic cytokines that play an important role in leucocyte trafficking and angiogenesis and are highly induced in infarcts. Tryptase, a proteinase-activated receptor (PAR)-2 agonist, induced endothelial expression of the angiogenic chemokines CCL2/MCP-1 and CXCL8/IL-8, but not the angiostatic chemokine CXCL10/IP-10. Endothelial PAR-2 stimulation with the agonist peptide SLIGKV induced a similar chemokine expression profile. Mast cell tryptase may exert its angiogenic effects in part through selective stimulation of angiogenic chemokines. Copyright (C) 2004 Pathological Society of Great Britain and Ireland. Published by John Wiley Sons, Ltd.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available