Functional implication of secretory proteases derived from microglia in the central nervous system

We have demonstrated that microglia produce certain secretory proteases which have been found to be important determinants of microglial properties, in surrounding cells and regenerative processes. In recent years, it has become clear that secretory proteases, particularly PGn-PA (plasminogen-plasminogen activator) system, work not only on catalysis of proteins in the extracellular space but also on cell growth, cell function, differentiation, proliferation and remodeling. These diverse effects may be derived from the unique structures of these enzymes, including their accessary domains. In particular, kringle domains have been shown to be important for interactions with other proteins. The results of these studies indicate that microglial secretory proteases participate to a great extent in physiological processes involving the regulation of neuronal growth, neuronal function and regenerative stages in the CNS.