Single cell sequencing data supporting "IL-4/C1q activated astrocyte-derived extracellular vesicles promote stroke infarct recovery by recruiting peripheral leukocytes"

This study aims to engineer an injectable biomaterial platform to promote brain repair post-stroke. We used extracellular vesicles derived from reactive astrocytes and decorated them onto the surface of hydrogel microparticles. Then they were injected into stroke cavity and crosslinked into porous scaffold in situ, which enabled persistent and uniform distribution of astrocyte-derived extracellular vesicles. Extracellular vesicles from reactive astrocytes activated with different cytokines showed different brain regeneration outcomes. IL-4/C1q activated astrocyte extracellular vesicles promoted robust angiogenesis within the stroke infarct and improved functional recovery significantly. Single-cell RNA sequencing was performed to characterize cellular and transcriptional changes in the post-stroke brain following implantation of extracellular vesicle-functionalized hydrogel microparticles. Briefly, ischemic stroke was induced in mice, and different hydrogel microsphere formulations were implanted into the infarct cavity at 5 days post-stroke. Ipsilateral hemispheres were collected at day 14 and dissociated into single-cell suspensions for transcriptomic profiling. The dataset was used to evaluate treatment-associated differences in cell composition, immune infiltration, vascular remodeling, and regenerative responses in the injured brain. From these data, we showed that IL-4/C1q extracellular vesicle group recruited reparative macrophages and neutrophils to promote brain repair post-stroke.