IL17A and Guillain-Barre syndrome: Although the mechanism of action of IL17 in GBS and EAN remains unclear, it mainly acts as a proinflammatory cytokine that upregulates the expression of inflammatory genes including proinflammatory chemokines, hematopoietic cytokines, acute phase response genes, and antimicrobial substances [33] in neutrophils, macrophages, and endothelial cells [34].