Stool Glial Fibrillary Acidic Protein Is Elevated in Progressive Multiple Sclerosis

Area of Science:

• Neuroimmunology
• Gastroenterology
• Microbiome research

Background:

• Multiple sclerosis (MS) is linked to gut microbiota and intestinal changes.
• Enteric glial cells, expressing GFAP and S100β, influence gut nervous and immune systems.
• Current serum markers like GFAP and neurofilament light chain predict worsening but don't distinguish MS subtypes.

Purpose of the Study:

• To investigate enteric glial cell function in MS.
• To assess stool GFAP (st-GFAP) as a potential biomarker differentiating MS disease courses.

Main Methods:

• Enzyme-linked immunosorbent assay (ELISA) measured st-GFAP in healthy controls (HCs), relapsing-remitting MS (RRMS), and progressive MS (ProgMS) patients.
• Clinical follow-up at 2 and 5 years assessed disease progression.
• Enteric glial hyperplasia was examined via GFAP and S100β immunoreactivity in colonic and duodenal tissue.

Main Results:

• st-GFAP levels were significantly higher in ProgMS compared to RRMS and HCs.
• st-GFAP correlated positively with baseline and longitudinal Expanded Disability Status Scale (EDSS) scores and 25-foot walk time.
• Enteric glial hyperplasia was observed in a primary progressive MS patient's colonic mucosa.
• st-GFAP showed a negative association with *Eubacterium hallii* in ProgMS patients.

Conclusions:

• Exploratory findings suggest an altered enteric glial phenotype in progressive MS.
• st-GFAP may serve as a prognostic biomarker for MS disease progression.