TNF and pneumonia: The severity of the pneumonia is caused by the great accumulation of neutrophils, increased reactive oxygen species (ROS) production, and enhanced proinflammatory cytokines production, such as tumor necrosis factor (TNF-α), interleukin-1β (IL-1β) and IL-6, which exacerbate the inflammation, leading to secondary diffuse lung parenchymal damage in the alveoli [3].