Synthesis of sulfated glycoproteins by glial precursor cells.

Populations of enriched glial precursor cells and astrocytes isolated from primary cultures of newborn rat brain were used to study the synthesis of sulfated glycoproteins. Both cell types incorporated [3H]glucosamine and [35S]sulfate into carbohydrate side chains of proteoglycans and glycoproteins. The rate of incorporation of [3H]glucosamine into the oligosaccharides and the pattern of distribution of the label into high mannose and complex glycopeptides recovered from the glycoproteins appeared to be similar for the two glial cell types. However, clear differences were noted in the rate of oligosaccharide sulfation activities. Thus the cultures of precursor glia were about four times more active than cultures enriched in astroglia in their ability to incorporate [35S]sulfate into glycoproteins.