Neuroimmune–oligovascular signaling shapes oligodendrocyte precursor cell fate and repair after ischemic stroke

BACKGROUND: Ischemic stroke causes neuronal and oligodendroglial injury, axonal and myelin damage, and neurovascular unit dysfunction. Oligodendrocyte precursor cells (OPCs) are lifelong progenitors that generate oligodendrocytes while receiving and transmitting signals within neural, immune, and vascular microenvironments. This review examines how neuroimmune-oligovascular communication and intracellular signaling shape OPC survival, recruitment, state transitions, differentiation, and remyelination after ischemic stroke. MAIN BODY: We first define OPC lineage identity, functional heterogeneity, and signaling interfaces with neurons, microglia/macrophages, astrocytes, endothelial cells, and pericytes. We then examine how excitotoxic, metabolic, redox, inflammatory, vascular, extracellular-matrix, and regulated cell-death signals converge on OPCs across lesion compartments and disease phases. Severe core ischemia depletes the progenitor pool, whereas partially perfused peri-infarct tissue permits reactive proliferation and migration. During the subacute phase, intercellular signals within the post-ischemic niche influence whether recruited OPCs adopt inflammatory, angiogenic, differentiation-competent, or arrested states. Long-term repair ultimately depends on lineage completion and stable myelin formation rather than OPC accumulation alone. The strongest causal evidence supports signaling from the surrounding niche as a regulator of OPC differentiation and demonstrates that OPC-derived myelin repair contributes to neuronal preservation and functional recovery. By contrast, evidence that endogenous OPCs themselves substantially regulate post-stroke inflammation, angiogenesis, blood-brain barrier integrity, or synaptic reconstruction remains less complete and often derives from culture, conditioned-medium, pharmacological, or transplantation paradigms. Therapeutic strategies are therefore organized according to the signaling and lineage bottleneck they target, including acute OPC preservation, niche remodeling, lineage completion, oligovascular reconstruction, and cell-based interventions. CONCLUSIONS: OPC fate after ischemic stroke is determined by the interaction of cell-intrinsic signaling competence with temporally and spatially changing neuroimmune-oligovascular cues. Translation will require lineage-resolved causal studies, human spatial and longitudinal validation, signaling-linked target-engagement measures, and treatment strategies matched to lesion phase, compartment, and repair bottleneck. A cell-communication framework may therefore provide a more mechanistically testable basis for OPC-centered white-matter repair after stroke.