Glial cell lineage in the cerebral cortex: a review and synthesis.

The present review is focused on the cell lineage relationships underlying gliogenesis in the cerebral cortex. Studies conducted both in vivo and in vitro suggest that the process of cortical gliogenesis involves a hierarchy of progressively restricted progenitor cell pools. In the cerebral cortex, as well as other areas of the central nervous system, glial cells differentiate from one another through a series of steps that can be defined at molecular, structural, and functional levels. Although the precise timing, sequence, and diversity of the steps involved in cortical gliogenesis are still not fully defined, the emerging picture suggests that both cell lineage and cell-cell interactions play a synergetic role in the determination and maintenance of the proper blend of glial cells in the cerebrum.