Activation of matrix-degrading metalloproteinases by mast cell proteases in atherosclerotic plaques

Jason L. Johnson*, Christopher L. Jackson, Gianni D. Angelini, Sarah J. George

*Corresponding author for this work

    Research output: Contribution to journalArticle (Academic Journal)peer-review

    213 Citations (Scopus)


    Recent studies suggest that mast cell-derived neutral proteases can activate matrix-degrading metalloproteinases (MMPs). We have investigated the role of the mast cell proteases tryptase and chymase in the activation of MMPs in human carotid endarterectomy specimens (atherosclerotic, n=32) and postmortem carotid arteries (control, n= 17). In vitro degranulation of mast cells in atherosclerotic carotid arteries by compound 48/80 caused a significant increase in MMP activity. Addition of the nonselective tryptase inhibitor antipain, the specific trypsin-like protease inhibitor 4- amidinophenylmethanesulfonyl fluoride, and the chymase inhibitor chymostatin reduced this increase in MMP activity by 30 ± 6%, 23 ± 6%, and 9 ± 2%, respectively. Immunocytochemistry identified significantly higher numbers of tryptase-containing cells (mast cells) and cells expressing MMP-1 and MMP-3 in the 'shoulder' regions of atherosclerotic artery lesions compared with the tunica media of control arteries. Dual immunocytochemistry showed collocation of MMP-1 and MMP-3 with mast cells in the shoulder regions. Degranulation was observed in 78±5% (mean±SEM) of mast cells in this area, whereas nonactivated mast cells were observed in all other areas. In situ zymography revealed caseinolytic and gelatinolytic activity in these areas. In conclusion, in vitro mast cell degranulation, which releases mast cell proteases, in carotid arteries increases MMP activity. Furthermore, elevated MMP-1 and MMP-3 expression is collocated with increased numbers of degranulated mast cells and with greater MMP activity in the shoulder regions of atherosclerotic plaques. Activation of MMPs by mast cell-derived proteases may be an important mechanism in atherosclerotic plaque destabilization.

    Translated title of the contributionActivation of matrix degrading metalloproteinases by mast cell proteases in atherosclerotic plaques
    Original languageEnglish
    Pages (from-to)1707-1715
    Number of pages9
    JournalArteriosclerosis, Thrombosis, and Vascular Biology
    Issue number11
    Publication statusPublished - 1 Jan 1998


    • Atherosclerosis
    • Mast cells
    • Matrix metalloproteinase
    • Plaque rupture
    • Tryptase


    Dive into the research topics of 'Activation of matrix-degrading metalloproteinases by mast cell proteases in atherosclerotic plaques'. Together they form a unique fingerprint.

    Cite this