Angiogenesis Factors as Emerging Circulating Biomarkers in Asthma.

Angiogenesis is an important event in the development of allergic inflammation as well as in the pathophysiology of tissue remodeling in asthma. Increased angiogenesis is a well-documented feature of airway remodeling in asthma. Angiogenesis refers to the formation of new blood vessels from pre-existing endothelium. Angiogenesis can be initiated by endogenous angiogenic factors released from mesenchymal cells or inflammatory cells. Under physiological conditions, angiogenesis is controlled by an equilibrium between pro-endogenous and anti-endogenous angiogenic factors released from the extracellular matrix to become bioavailable. The presence of increased size and number of bronchial blood vessels indicates that angiogenesis plays a crucial role in tissue growth and remodeling in asthma. However, the diagnostic significance of circulating angiogenic factors in asthma remains unclear. This review summarizes the role of angiogenesis in airway remodeling in asthma, and the potential diagnostic implications of circulating angiogenetic factors.