- Oligodendrocyte progenitor cells (OPCs) are a distinct population of neural precursor cells in the central nervous system (CNS) that serve as the primary source of oligodendrocytes—the myelin-producing cells that insulate neuronal axons and enable rapid signal conduction.
- OPCs are characterized by their ability to proliferate, migrate, and differentiate into mature oligodendrocytes, particularly during development and in response to injury or demyelination. They play a critical role in both CNS development and repair, making them essential for maintaining white matter integrity throughout life.
- During embryogenesis, OPCs originate from specific regions of the neural tube, including the ventral forebrain, spinal cord, and other germinal zones. These cells undergo extensive proliferation and migration to populate the developing CNS. Once in their proper locations, OPCs begin to differentiate into pre-oligodendrocytes and eventually mature oligodendrocytes, which extend processes to wrap axons with compact myelin sheaths. Myelination, driven by this process, is vital for efficient action potential propagation and overall neurological function.
- In the adult CNS, OPCs persist as a widespread and dynamic cell population, comprising approximately 5–8% of all glial cells. They retain the capacity to divide and are continuously surveying their local environment. Importantly, adult OPCs are crucial for remyelination—the regeneration of myelin sheaths following damage due to trauma, inflammation, or demyelinating diseases like multiple sclerosis (MS). In MS, for example, OPCs are recruited to demyelinated lesions where they attempt to differentiate and restore lost myelin. However, this process can be impaired due to inflammatory signals, extracellular matrix changes, or age-related decline in OPC function.
- OPCs are identified by a combination of molecular markers, including NG2 (nerve/glial antigen 2) and PDGFRα (platelet-derived growth factor receptor alpha). These markers distinguish OPCs from other glial cells and highlight their proliferative and migratory capabilities. NG2-glia (another name for OPCs) are also recognized for their unique electrophysiological properties, including the ability to receive synaptic input from neurons—an unusual feature among glial cells. This suggests that OPCs not only respond to local damage or demyelination but also integrate signals from neural activity, potentially influencing their behavior in an activity-dependent manner.
- Recent research has expanded the understanding of OPCs beyond their role in oligodendrogenesis. Studies suggest that OPCs may also contribute to neuronal circuit modulation, axonal support, and immune responses within the CNS. Additionally, their dysfunction has been implicated in various neurological disorders beyond MS, including schizophrenia, Alzheimer’s disease, and cerebral palsy, where abnormal OPC development or maturation may lead to insufficient myelination or disrupted neural connectivity.
