GFAP and viral encephalitis: Indeed, most studies of biomarkers in CSF from patients with CNS neurological conditions show a pattern more suggestive of cytokine release syndrome than antibody-mediated encephalitis, with increased levels of soluble mediators produced by the innate immune system (IL-6, TNF-α) and glial markers (GFAP), but with absence of intrathecal IgG synthesis and normal levels of chemokines associated with B/T-cell recruitment (CXCL13) [21–23].