Identification of SARS-CoV-2-specific cytotoxic lymphocytes in cerebrospinal fluid of a patient with cerebral demyelination Post mRNA vaccination

This is the authors' abstract. We don't add key points for this paper.

Introduction Some cerebral demyelinating lesions occur after vaccination. We aimed to elucidate the precise roles of vaccine-activated immune cells and antigen-specific lymphocytes in the central nervous system of a patient who developed cerebral demyelination after vaccination. Methods Using comprehensive single-cell RNA sequencing and immune repertoire analysis combined with a lymphocyte stimulation assay, we characterized the immunological landscape of a patient who developed right-hand clumsiness after receiving an mRNA vaccine against SARS-CoV-2 and was subsequently diagnosed with tumefactive cerebral demyelination. Results Natural killer cells and effector CD8+ T cells in the cerebrospinal fluid were more cytotoxic and activated than those in healthy controls. Effector CD8+ T cells specific to SARS-CoV-2 spike peptides were identified in the cerebrospinal fluid. The proportion of these cells in peripheral blood decreased after corticosteroid therapy, in parallel with clinical improvement and a reduction in lesion size. Discussion Although a direct causal relationship between vaccination and demyelination remains uncertain, our findings suggest that vaccine-activated cytotoxic lymphocytes contribute to immune-mediated demyelinating events in the central nervous system.