TNF and Bell's palsy: We also know that cell-mediated autoimmune mechanisms may be relevant in the pathogenesis of Bell’s palsy, as demonstrated by the elevated concentrations of the cytokines interleukin-1 (IL-1), IL-6, and tumor necrosis factor-alpha (TNF-alpha) in patients with Bell’s palsy, compared with control populations, suggesting an activation of cell-mediated effectors [40].