TNF and Keratoconjunctivitis sicca: Long-term dry eye has been reported with increased expression of inflammation factors such as tumor necrosis factor-alpha (TNF-α), matrix metalloproteinase (MMP)-2, MMP-9, intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) in the ocular surface7, 8, 9, 10, 11.