TNF and myasthenia gravis: To further investigate the molecular mechanism of MG-induced tracheal epithelial barrier damage, we analysed the expression of TNF-α-NF-κB/MLCK pathway-related proteins, including IκBα, p-IκBα, p65, p-p65, TNF-α, MLCK, MLC2, and P-MLC2, by protein blotting (p < 0.01).