TNF and chronic obstructive pulmonary disease: The noxious particles in biomass smoke induce an inflammatory response through: upregulation of pro-inflammatory cytokines such as interleukin 6 (IL-6), tumor necrosis factor alpha (TNFα), and granulocyte colony stimulatory factor (G-CSF); recruitment of immune cells, such as macrophages and neutrophils; upregulation of gelatinases (matrix metalloproteinase 2 and 9); and epithelial-mesenchymal transition (EMT), thereby reducing lung function and contributing to the onset/progression of COPD [25–27].