Role of Transforming Growth Factor-β in Airway Remodeling in Asthma

TGF-beta is one of the main mediators involved in tissue remodeling in the asthmatic lung. This profibrotic cytokine is produced by a number of cells, including macrophages, epithelial cells, fibroblasts, and eosinophils. High expression of TGF-beta in patients with asthma was reported by many investigators. However, controversy remains whether the concentration of TGF-beta correlates with disease severity. TGF-beta is believed to play an important role in most of the cellular biological processes leading to airway remodeling. It was shown to be involved in epithelial changes, subepithelial fibrosis, airway smooth muscle remodeling, and microvascular changes. Here, sources of TGF-beta, as well as its role in the development of airway remodeling, will be reviewed. Therapeutic strategies that modulate TGF-beta will also be discussed.