TNF and Keratoconjunctivitis sicca: For example, as a representative cytokine, IL-17 participates in the damage of the peripheral glands and is highly expressed in the peripheral blood of SS patients In addition to participating in peripheral gland inflammation, TNF-α also affects the expression of AQP5 in peripheral secreting glands through the NF-κB pathway and has been shown to influence the xerostomia and xerophthalmia symptoms in SS patients.[41]