Longitudinal in vivo imaging of dynamic immune-vascular responses to meningeal cerebrovascular injury.

Meningeal cerebrovascular injuries (mCVI) trigger prolonged bleeding and inflammation that contribute to long-term neurological dysfunction, yet the immune–vascular dynamics governing meningeal repair remain poorly understood. Existing animal models limit direct observation of these processes due to invasive procedures and restricted optical access through opaque skulls. With a thin, translucent skull, the zebrafish provides an idea model for longitudinal imaging of mCVI sequelae in intact, unmanipulated animals. We have established an adult zebrafish model to investigate mCVI using precisely calibrated sonication to rupture meningeal blood vessels without breaching the skull or damaging the underlying brain. Using longitudinal live imaging of intubated adult zebrafish, we directly visualize vascular disruption, blood flow dynamics and preservation, angiogenic regrowth and pruning, and immune cell population dynamics over time in the same animal with unprecedented resolution. Together, these studies unveil the meninges as a dynamic immune–vascular niche and demonstrate that our newly developed zebrafish mCVI model provides a powerful platform for longitudinal live imaging, opening the door to new insights into chronic neuroinflammatory disease at CNS borders.