LINES OF MURINE OLIGODENDROGLIAL PRECURSOR CELLS IMMORTALIZED BY AN ACTIVATED NEU TYROSINE KINASE SHOW DISTINCT DEGREES OF INTERACTION WITHAXONS IN-VITRO AND IN-VIVO

Replication-defective retroviruses expressing the t-neu oncogene, or a hybrid protein with the neu tyrosine kinase linked to the external re gion of the human epidermal growth factor receptor (egfr-neu), were us ed to establish lines of murine oligodendroglial precursor cells. Diff erentiation of the t-neu lines into myelin-associated glycoprotein (MA G)-positive oligodendrocytes was induced by dibutyryl cAMP, and the eg fr-neu line showed limited differentiation in vitro upon withdrawal of epidermal growth factor. Cerebellar granule cell neurons expressed mi togens for the cell lines. Upon transplantation into demyelinated lesi ons, t-neu line cells engaged with the demyelinated axons whereas the egfr-neu line cells differentiated further and ensheathed the axons. T hese cell lines thus interact with neurons in vitro and in vivo and ca n be used as tools to define the molecules involved in different stage s of neuron-glia interaction.