title: Use of inhibitory (anti-catalytic) antibodies to study extracellular proteolysis.
abstract: The specific role of proteolytic enzymes in the degradation by live cells of fibrillar model matrices (fibrin, collagen) was studied using monoclonal and polyclonal inhibitory (anti-catalytic) antibodies. Dissolution of fibrin by plasminogen-supplemented human HT-1080 cells was blocked by (1) omission of plasminogen, (2) inhibitory anti-plasmin antibody, and (3) inhibitory anti-u-PA antibody but not by non-inhibitory control antibodies. Using a similar approach, it was shown that the dissolution of reconstituted type I collagen fibrils by trypsin-supplemented live human skin fibroblasts was blocked by inhibitory antibodies to fibroblast-type procollagenase but not by noninhibitory control antibodies. These findings permit us to deduce that, at least in culture, the dissolution of fibrin by plasminogen-supplemented HT-1080 cells was mediated by plasminogen-assisted proteolysis which entailed the extracellular conversion of plasminogen to plasmin by cell-derived u-PA, and that the dissolution of collagen fibrils by trypsin-supplemented skin fibroblasts was mediated by a collagenase-dependent pathway.
authors.affiliation: Department of Oral Biology, University of Alabama School of Dentistry, Birmingham 35294.
authors.forename: H
authors.initials: H
authors.lastname: Birkedal-Hansen
authors.forename: B
authors.initials: B
authors.lastname: Birkedal-Hansen
authors.forename: L J
authors.initials: LJ
authors.lastname: Windsor
authors.forename: H Y
authors.initials: HY
authors.lastname: Lin
authors.forename: R E
authors.initials: RE
authors.lastname: Taylor
authors.forename: W G
authors.initials: WG
authors.lastname: Moore
mesh_terms: D000906:Antibodies; D002460:Cell Line; D003094:Collagen / Q000378:metabolism; D005109:Extracellular Matrix / Q000378:metabolism*; D005337:Fibrin / Q000378:metabolism; D005341:Fibrinolysin / Q000037:antagonists & inhibitors / Q000378:metabolism; D006801:Humans; D003012:Microbial Collagenase / Q000037:antagonists & inhibitors / Q000378:metabolism; D010447:Peptide Hydrolases / Q000276:immunology / Q000378:metabolism*; D010958:Plasminogen / Q000378:metabolism
chemical_list: D000906:Antibodies; D005337:Fibrin; D010958:Plasminogen; D003094:Collagen; D010447:Peptide Hydrolases; D005341:Fibrinolysin; D003012:Microbial Collagenase