TLR4 mediates the pathogen-induced activation of NF-κB in endothelial cells through the homologous structure of intracellular IL-1 receptor, which subsequently initiates the downstream MyD88 signaling pathway, resulting in the secretion of immune-inflammatory cytokines and the development of COPD [46]. Here, NFKB1 is linked to chronic obstructive pulmonary disease.