We investigated whether plasma neurofilament light chain (pNfL) and glial fibrillary acidic protein (pGFAP) serve as sensitive biomarkers of neurological involvement and response to immunosuppressive therapy.<h4>Methods</h4>Plasma samples from 55 patients with genetically confirmed AGS and 55 age- and sex-matched healthy controls were analyzed using single molecule array assays. The gene discussed is GFAP; the disease is Aicardi-Goutieres syndrome.