Expression of v-src arrests murine glial cell differentiation.

A replication-defective retroviral vector carrying the v-src oncogene and the gene for neomycin resistance was used to infect neurone- and fibroblast-depleted embryonic mouse brain cells in vitro. Cells resistant to the antibiotic G418 were obtained and continually passaged. Several cell lines were isolated which express high levels of v-src mRNA and v-src tyrosine kinase activity. The antigenic marker profile of either the pooled cells from an individual infection or sublines isolated from individual foci showed the cells to be immature glia: most cells expressed vimentin, A2B5 antigen and/or J1/tenascin glycoproteins, but not fibronectin. Sublines expressed different antigen profiles suggesting that the immortalised cells were derived from glial cells of different phenotypes. The cell lines expressed the 120 and 140 but not the 180 kd components of N-CAM as well as voltage-activated potassium channels, typical for glial cells. 01 antigen-positive oligodendrocytes were never observed in the lines or sublines after long term passage (over 1 year), but some cells expressed glial fibrillary acidic protein, a marker for mature astrocytes. Thus, expression of v-src in murine glial cells appears to arrest their development and prevent their differentiation.