Table 1.

Mechanisms of cell surface binding of proteinases

Binding mechanism	Proteinases bound	Cell types	Proteolytic Activities
Transmembrane Domain	MT1-MMP MT2-MMP MT3-MMP MT5-MMP	Epithelial cells Tumor cells Fibroblasts Macrophages	ECM degradation, tumor invasiveness Pro-MMP-2 &-13 binding and activation, TNF-α activation, proteinase inhibitor degradation
	ADAMs	Epithelial cells Endothelial cells Fibroblasts Smooth muscle cells Inflammatory cells Tumor cells	Shedding of membrane- associated cytokines, apoptosis ligands, growth factors and receptors for these molecules Pro-urokinase activation
	Type II serine proteases(matriptase)	Monocytes, B lymphocytes
GPI anchor	uPAR and urokinase	PMN mononuclear phagocytes Fibroblasts Epithelial cells Smooth muscle cells	Fibrinolysis Activation of latent growth factors & proMMPs
	MT4-MMP	CNS eosinophils	ECM degradation proMMP-2 activation
	MT6-MMP	PMN	ECM degradation
Proteoglycans	Pro- and active MMP-2, -7, -9, and -13	Uterine epithelial cells	ECM degradation Host defense
	NE, CG, PR3	PMN, macrophages	Wound healing Inflammation
Integrins	β2: Pro-MMP-9 & -8, NE, CG	PMN	Unknown
	α2β1: MMP-1	Keratinocytes	Cell migration
	αvβ3: MMP-2	Endothelial cells & melanoma cells	Tumor invasiveness and neovascularization
TIMP-2	Pro-MMP-2 and proMMP-13	Fibroblasts Endothelium Tumor cells	ECM degradation Tumor invasiveness
CD44	MMP -2 & MMP-9	Tumor cells & keratinocytes	ECM degradation, activation of latent TGF-β
	MMP-7	Tumor cells & epithelial cells	Post partum uterine involution, and lactation through HB-EGF shedding
Tissue factor	Factor VII	Monocytes/macrophages	Activation of actor VII and other serine proteases involved in thrombosis
High-molecular- weight Kininogen	Prekallirein	Endothelial cells	Factor XI activation leading to thrombosis Bradykinin generation Pro-urokinase activation
P11	Cathepsin B	Tumor cells	Tumor growth and metastasis
Unknown	Cathepsin B	Macrophages, CTLs	Elastin degradation, degradation of perforins

Legend for Table 1. ECM, extracellular matrix; PMN, polymorphonuclear neutrophils; TNF-α, tumor necrosis factor- α; GPI, glycosyl phosphatidyl inositol; CNS, central nervous system; NE, neutrophil elastase; CG, cathepsin G; PR3, proteinase 3; TGF-β, transforming growth factor- β, HB-EGF, heparin binding epidermal growth factor; CTLs, cytotoxic T lymphocytes