Respiratory epithelial imbalances in asthma pathophysiology.

: The pathophysiology of asthma is complex and involves a number of factors including atopy and bronchial hyperreactivity. A strong body of evidence suggests that structural and functional respiratory epithelial alterations play a crucial role in both development and persistence of this condition. From the onset of symptoms the airways epithelium of asthmatic patients seems to be altered and unable to repair. The interactions between the epithelium and the underlying mesenchyma, which are jointly referred to as the epithelial-mesenchymal trophic unit (EMTU), are thought to result in a self-sustaining damage of the airways and, ultimately, in a chronic inflammatory scenario. A better understanding of the relationship occurring across EMTU, environmental noxae, and factors of susceptibility to epithelial damage is likely to pave the way to future new preventive and therapeutic strategies for this condition.