Asthma--something old, something new ...

Abstract

Asthma is an inflammatory disease characterized by infiltration of the airways by eosinophils and ensuing bronchial hyperresponsiveness. The activation of eosinophils and their recruitment to the airways are strongly influenced by T-lymphocytes and their products. There is now evidence that successful therapy of asthma results in changes in the ratios of helper and suppressor T-lymphocytes both in the circulation and in bronchoalveolar lavage fluid. Theophylline, a drug which has been used in asthma therapy for many years, provides additional benefit for patients already treated with effective doses of beta-agonists and/or corticosteroids. The effects of theophylline on lymphocyte traffic and function have not been studied extensively. However, there is evidence from studies conducted in renal transplant recipients and patients with asthma that theophylline increases the numbers and activity of suppressor T-lymphocytes in the peripheral circulation. This property of theophylline may provide a therapeutic benefit in the treatment of asthma, one that is distinct from its activity as a bronchodilator.