GFAP and Parkinson disease: Immunologic profiling of colonic biopsies obtained from PD patients (n = 14) and matched healthy controls (n = 14) showed increased mRNA expression of TNF‐α, IFN‐λ, IL‐1β, and IL‐6 as well as the glial markers, glial fibrillary acidic protein (GFAP) and Sox‐10, particularly in the ascending colon of PD patients [75].