IL6 and infection: The innate immune system directly stimulates macrophages and epithelial cells to produce TNF-α, Transforming Growth Factor β1 (TGF-β1), IL-6, and IL-8, which lead to the loss of cell adhesion proteins, such as adherens and tight junctions [85,86], resulting in cell barrier damage, impaired bronchial mucociliary function, and an increased risk of infections [87].