Various methodologic aspects should, however, be taken into account when studying these effects.
For example, some agents could possibly be more effective at preventing than reversing airway remodeling, and the duration of treatment and doses of the agents should be considered, as well as the type and duration of the disease. Research on gene therapy in lung diseases is currently under scrutiny. Other than CF or a1-antitrypsin deficiency, it is highly unlikely that a single vector will be therapeutic, as multiple genes are implicated in asthma and COPD diseases. Gene therapy has been studied mostly in relation to CF. Vectors and incorporating techniques need to be optimized to prove helpful in treatment of CF patients. Overall, primary prevention of airway disease is likely to be the most effective tool and can be achieved by allergen avoidance, smoking avoidance, control of infections, or prenatal diagnosis. Treatment of other allergic diseases might possibly prevent the development of asthma, especially in allergic rhinitic subjects and in subjects with asymptomatic AHR and has to be further studied.
Although this is still controversial, we have evidence that the airway remodeling process may have untoward consequences in obstructive diseases, in the clinical expression of the disease, in its development, and in the decline in pulmonary function. The common factor underlying all the structural changes in airway diseases is an injury/repair process. In asthma, the damage follows an allergenic or nonal-lergenic Th2 inflammation and mechanical stress. In COPD, the initial trigger is cigarette smoke inducing direct cell toxicity and inflammatory response. An infectious process is both at the origin of the inflammation observed in CF and bronchiectasis patients. More research should be done to identify key changes, effective treatments, and proper interventional timing to counteract these changes. The prevention of the development of asthma, COPD, or other airway diseases through early interventions on structural changes is an exciting avenue. The potential of novel therapeutic agents to reverse or prevent airway remodeling warrants further evaluation.