OLFACTORY ENSHEATHING GLIA AND PLATELET-DERIVED GROWTH-FACTOR B-CHAINREACTIVITY IN THE TRANSPLANTED RAT OLFACTORY-BULB

Using a monoclonal antibody against the B-chain of platelet-derived gr owth factor as a marker, we have examined the behavior of olfactory en sheathing glia in the normal and transplanted rat olfactory bulb. In t he normal postnatal olfactory bulb, these glia are found to ensheath t he bundles of incoming primary olfactory nerve fibers as well as those in the olfactory nerve layer. Olfactory marker protein antibody was u sed to identify the olfactory nerve proper. Within the transplant, the same glia: (1) ensheath bundles of both primary olfactory and non-pri mary olfactory axons, (2) ensheath axonal bundles deep within the dono r tissue, and (3) eventually permit radiation of individual axons from bundles to surrounding neuropil. We believe that ensheathing glia (be ing rich in growth-related factors and extracellular matrix molecules) may be useful in providing trophic support and guidance for the recon struction of developmentally or traumatically damaged neuronal pathway s not directly related to the olfactory system. The evidence presented here indicates that ensheathing glia are capable of existing in deep brain areas and ensheathing other than primary olfactory axons. The sp ecial molecular characteristics of these glia along with the morpholog ical findings presented here provide a foundation for further studies of these unique glia and their potential utility in the restoration of damaged neural pathways.