Single-cell transcriptome profiling reveals dynamic cell populations and immune infiltration in cerebral cavernous malformation.

Introduction: The cellular subpopulations and signaling pathways in the pathological tissues of cerebral cavernous malformation (CCM) remain incompletely understood. To gain a deeper understanding of the pathogenesis of CCM, we aimed to comprehensively map the cellular subpopulations and signaling pathway alterations in the pathological tissues of sporadic CCM patients. Methods: Lesional brain vascular tissues from CCM patients and normal brain vascular tissues from controls were collected. Multiplex fluorescent immunohistochemistry and single-cell RNA sequencing were performed on the lesional tissues. Differential gene expression, pathway enrichment analysis, and cell-cell communication analysis were conducted to investigate disease-related changes. Results: We identified 8 major cell types in the lesion tissues of CCM patients. We observed an increased proportion of monocytes, neutrophils, and NK cells in the lesion tissues of CCM patients. Twenty-eight significantly differentially expressed genes were identified, and pathways such as NK cell-mediated cytotoxicity showed alterations. Cell-cell communication analysis revealed an increase in both the types and strength of communication between cells in the CCM lesion tissues. Conclusion: This study provides the single-cell transcriptomic analysis of CCM lesions, revealing increased monocytes, neutrophils, and NK cells, along with dysregulated gene expression and signaling pathways. Enhanced intercellular communication, particularly via VEGF and ADGRE5 pathways, highlights potential therapeutic targets for CCM.