Single-cell RNA-sequencing-based dissection of peripheral-blood immune-cell heterogeneity and differential gene-expression signatures in neuromyelitis optica spectrum disorder

ObjectiveIn this study, single-cell RNA sequencing technology was used to characterize the differences in the cellular composition, differentially expressed genes and cellular pathways in the peripheral blood from neuromyelitis optica spectrum disorder (NMOSD) patients and healthy controls thereby revealing the role of key cells and signaling pathways in the NMOSD microenvironment.MethodsPeripheral blood samples were collected from 5 NMOSD patients and 5 healthy volunteers. Single cell sequencing technology was used to sequence peripheral blood mononuclear cells of the subjects, and the clinical data were analyzed to identify the differential genes between NMOSD patients and healthy people. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were used to analyze the biological functions and pathways of differential genes.ResultsWe identified 143 up-regulated degs and 129 down-regulated degs. Functional enrichment results showed that these genes were significantly enriched in pathways such as immune response, inflammatory response, cell cycle and metabolism. In peripheral blood of the NMOSD group, the percentages of B cells, CD4+ T cells and CD8+ T cells were relatively decreased, while the percentages of CD14+ monocytes, CD16+ monocytes, natural killer (NK) cells and neutrophils were relatively increased. Three up-regulated genes (S100A9, MNDA, S100A8) and down-regulated genes (RPL13A, RPS2, RPS4X) were selected from the differential genes of immune cells, and these genes may play an important role in neuroinflammation.ConclusionsThis study provides a new perspective for the future research and treatment of NMOSD by analyzing and identifying specific immune cell subsets in the peripheral blood of NMOSD and healthy people.