Figure 4.

OPC cell fate decisions OPCs are multipotent and can differentiate into oligodendrocytes, astrocytes or SCs. OPC cell fate decisions are in part, dependent upon BMP signalling. When BMP signalling is blocked, such as when OPCs are in proximity to BMP suppressive astrocytes, OPCs predominantly differentiate into oligodendrocytes in vivo and in vitro. Conversely, when OPCs are exposed to high BMP signalling in culture, OPCs readily form astrocytes [76,77]; however, in vivo, few OPCs have been observed to produce astrocytes. Lineage tracing studies have demonstrated that following demyelinating injuries, adult OPCs can differentiate into SCs in astrocyte deficient areas [21]. Although BMP signalling is high within the lesion environment, BMP alone is not sufficient to produce OPC-derived SCs in vitro.