Gel-sol transition can describe the proteolysis of extracellular matrix gels

We monitored the cell-free solubilization of extracellular matrix and fibro nectin gels, catalyzed by exogenous proteinases. The corresponding measurem ents could not be interpreted according to usual proteinase kinetics. The o bservation that this experimental system did not consist in surface but in bulk degradation and appeared specific to gel substrates, incited us to use gelation-related approaches to describe these kinetics. We show that the g el-sol transition theory adequately describes the enzyme reactions. This al lowed formulation and experimental confirmation of a power law relating mac roscopic changes of the gel to enzyme kinetics. This approach could also be used for other power laws predicted by the gel-sol transition theory, allo wing a better understanding of macroscopic modification of the extracellula r matrix during proteolysis, which is implied in many biological situations , especially tumor dissemination. (C) 2000 Elsevier Science B.V. All rights reserved.