Project description:The enormous cellular diversity and complex tissue organization of the brain have hindered systematic characterization of its age-related changes in cellular and molecular architecture and mechanistic understanding of its functional decline and degeneration during aging. Here we generated a high-resolution cell atlas of brain aging within the frontal cortex and striatum using spatially resolved single-cell transcriptomics and quantified the changes in gene expression and spatial organization of major cell types in these regions over the lifespan of mice. We observed more pronounced changes in the composition, gene expression and spatial organization of non-neuronal cells over neurons. Our data revealed molecular and spatial signatures of glial and immune cell activation during aging, particularly within the white matter of the corpus callosum, and identified both similarities and differences in cell activation patterns induced by aging and systemic inflammatory challenge. These results provide critical insights into age-related decline and inflammation in the brain.
Project description:The glycocalyx is a critical but often underappreciated modulator of cellular behavior. Its diversity across cell types within tissues remains poorly understood, but recent advances in single-cell profiling now enable more precise analysis of cell surface composition. Here, we applied single-cell glycan and RNA sequencing to profile glycocalyx diversity across human and mouse ocular surface cell types. Glycocalyx patterns effectively distinguished epithelial subtypes, with corneal epithelial cells enriched in complex and high-mannose N-glycans, conjunctival cells in fucosylated structures, and goblet cells in O-glycans. We also observed dynamic changes during epithelial maturation, marked by regulated shifts in sialic acid structures. In the mouse ocular surface, glycocalyx patterns distinguished major cell types, but the glycan profiles differed from those in humans, pointing to species-specific features. These findings demonstrate that glycocalyx composition is closely linked to cell identity and maturation and provide a foundation for exploring its roles in tissue organization and disease.