Abstract
Several homologous connective tissue matrix degrading metalloproteinases, termed matrix metalloproteinase(MMPs), are secreted by resident tissue cells, infiltrating inflammatory cells, and tumor cells as inactive proenzymes that, upon activation, can degrade many of the connective tissue components. cDNA sequence analysis has revealed that these proteinases are composed of several modules, some of which appear to have been derived from matrix proteins. A family of specific tissue inhibitors of MMP(TIMPs) regulates the extracellular activity of MMPs. MMPs and TIMPs are differentially regulated in cells by growth factors, hormones and cell shape changes. Recent work has shown that lectins also stimulate MMP expression and suppresses TIMP levels in human fibroblasts indicating that naturally present lectins may also participate in regulating MW and TIMP gene expression in vivo.
