A NEURITE OUTGROWTH-INHIBITORY PROTEOGLYCAN EXPRESSED DURING DEVELOPMENT IS SIMILAR TO THAT ISOLATED FROM ADULT BRAIN AFTER ISOMORPHIC INJURY

The expression of proteoglycans (PGs) in the mammalian central nervous system (CNS) appears to be strictly regulated both during development and after damage to the mammalian CNS, Recently, we have isolated fro m membranes of injured adult brain a neurite outgrowth-inhibitory prot eoglycan (IMP), the activity of which could be specifically counteract ed by a monoclonal antibody (mAB) against the PG. We described in this report the characterization of perinatal membrane proteoglycan (PMP), a heparan-sulfate/chondroitin-sulfate-containing PG expressed during brain development. Its maximal expression was observed around postnata l day 3, decreasing strongly in normal adult tissue. This PG was purif ied and characterized using mABs generated against IMP, The comparison of PMP and IMP properties indicates that the two PGs are highly relat ed and share expression patterns, biochemical characteristics, and the ability to inhibit neurite initiation in culture. However, IMP and PM P displayed a distinct effect on neurite elongation, which may be expl ained by their differences in glycosilation pattern, The data presente d in this report support the idea that proteoglycans expressed during CNS development are re-expressed following injury. (C) 1998 John Wiley & Sons, Inc.