Chapter 10 - Progenitor Cells of the Adult Human Subcortical White Matter

Abstract

Oligodendrocyte progenitor cells (OPCs) seem to be extraordinarily widespread in the adult mammalian brain. The principal class of OPCs in adult rodents is a bipotential astrocyte-oligodendrocyte progenitor cell designated the O-2A progenitor, by virtue of its generation in vitro of oligodendrocytes and type 2 astrocytes, the latter comprising the traditionally recognized fibrous astrocytes of the white matter. OPCs may be specifically targeted and isolated from the white matter. This chapter outlines basic strategies for isolating OPCs from the adult white matter, using either fluorescence-activated cell sorting (FACS) or a higher-yield, less-specific alternative immunomagnetic isolation (MACS). Adult-human white-matter progenitor cells (WMPCs) give rise to multipotential neurospheres. Nonetheless, the very existence of multipotential progenitors scattered throughout the white-matter parenchyma forces one to reconsider understanding of both the nature and incidence of neural stem cells in the adult brain, and challenges the conception of the supposed rarity of adult neural progenitor and stem cells. In doing so, they point to an abundant and widespread source of cells that may be used both as a target for pharmacological induction and as a cell type appropriate for therapeutic engraftment to the diseased adult brain.