Single-cell RNA-seq analysis identifies distinct myeloid cells in COVID19 vaccination- associated encephalitis (set 1)

Background and Objectives Recently accumulating evidence demonstrates the rare occurrence of COVID19 vaccination- induced inflammation in the central nervous system. However, the precise immune dysregulation related to the COVID19 vaccination-associated autoimmunity remains elusive. Here we report a case of COVID19 vaccination-associated encephalitis, where single-cell RNA sequencing (scRNA-seq) analysis identified a distinct myeloid cell population in the blood during the acute phase of the disease. Methods Peripheral blood mononuclear cells (PBMCs) were analyzed by scRNA-seq to clarify the cellular components of the patients at both the acute and remission phases of the disease. The data obtained were compared to those acquired from a healthy cohort. Results In this study, scRNA-seq analysis of PBMCs identified a distinct myeloid cell population observed at the acute phase of encephalitis. The specific myeloid population was not detected both at the remission phase of the disease and the samples fromof a healthy cohort. Discussion Our findings illustrate the induction of a unique myeloid subset in COVID19 vaccination-associated encephalitis. Further accumulation of reports investigating the dysregulated immune signature of COVID19 vaccination-associated autoimmunity is warranted to clarify the pathogenic role of the myeloid subset observed in our study. Overall design: Comparative gene expression profiling analysis of single cell RNA-seq data for PBMCs of COVID19 vaccination-associated encephalitis patient and healthy donors.