Single-cell RNA-sequencing implicates venous endothelial cells as a source of VEGF-A-mediated neo-angiogenesis in neuroinflammation

Abstract

Histopathological studies of multiple sclerosis (MS), a demyelinating disease of the central nervous system (CNS), and its animal model experimental autoimmune encephalomyelitis (EAE) have found newly formed leaky vessels in demyelinated acute and chronic plaques, in addition to blood-brain barrier damage in existing vessels, that exacerbate disease pathology by increasing CNS infiltration of immune cells. However, which vessel subtypes and signaling pathways generate these aberrant vessels is poorly understood. Using single-cell RNA sequencing and in vivo validation, we find that transcriptome signatures of neo-angiogenesis arise in venous endothelial cells in both acute and chronic EAE, and correlate with upregulation in VEGF-A signaling. These neo-angiogenic markers are also increased in human MS lesions. Treatment with a VEGF-A blocking antibody ameliorates EAE pathology by reducing neo-angiogenic transcriptomic signatures in vivo, suggesting that VEGF-A drives angiogenesis from vein ECs in EAE. Our findings suggest novel therapies targeting the vasculature that could benefit chronic MS.

Distinct Th17 effector cytokines differentially promote microglial and blood-brain barrier inflammatory responses during post-infectious encephalitis

“…The endothelial response to GAS shares commonalities with the transcriptomes of CNS ECs in other inflammation and disease models 32,57,58 , including our scRNAseq findings in EAE 36 , such as upregulating antigen presentation and inflammation genes, and downregulating BBB-associated transcripts 33 . This suggests the presence of a core CNS EC transcriptional response module to neuroinflammation.…”

“…Since BBB disruption occurs in other models of neuroinflammation (e.g. EAE), we investigated how the transcriptional shifts identified by scRNAseq in OB ECs from GAS versus PBS conditions compare to those identified by scRNAseq in spinal cord ECs isolated from either acute or chronic EAE versus Complete Freund Adjuvant controls (CFA) 36 . The correlation analysis performed on all EC genes revealed that log 2 fold changes seen in ECs between GAS and PBS correlated more closely with acute (r 2 = 0.302), than chronic (r 2 = 0.1401) EAE ( Figure 2G ).…”