The development of myelin-forming glia: studies with primary cell cultures and immortalized cell lines.

The myelin-forming glial cells, oligodendrocytes and Schwann cells, undergo a sequence of maturation steps from precursor cell to mature myelinating cell. This includes migration from their site of generation to the axons they will myelinate. The recognition and interaction with the axons prior to the formation of compact myelin involve the interplay of a range of cell surface receptors and adhesion molecules, some of which have been defined. Signal transduction by such adhesion molecules may play a role in the recognition event. The generation of a range of immortalized cell lines and clones of oligodendroglial precursor cells and the analysis of their in vitro and in vivo properties have demonstrated the ability of these lines to recognize axons. They are providing useful tools to investigate the molecular basis of glia-neuron interactions.