ASSOCIATION OF GLUCOCEREBROSIDE HOMOLOG BIOSYNTHESIS WITH SCHWANN-CELL PROLIFERATION

The biosynthesis of myelin-associated glycolipids was studied in quies cent secondary cultures of Schwann cells and.in a rapidly proliferatin g population of transfected Schwann cells (TSC) by in vitro incorporat ion of [H-3]galactose. The TSC demonstrated a marked increase (>10-fol d) in [H-3]galactose incorporation when compared to quiescent Schwann cells. The level (or amount) of [H-3]galactose incorporation into lipi ds is dependent upon the number of TSC in culture. The majority of H-3 -labeled lipids were oligohexosylceramides (GL-2, GL-3, and GL-4). Sub strates that inhibit TSC proliferation, collagen type I and Matrigel(T M), an artificial basement membrane, decrease the [H-3]galactose incor poration by 25% and 80%, respectively. Our results indicate that the s ynthesis of glucocerebroside and its homologs is associated with Schwa nn cell proliferation.