Indexed on: 01 Sep '89Published on: 01 Sep '89Published in: Clinical Reviews in Allergy & Immunology
The airways have a repertoire of defense mechanisms against stimuli entering the tracheobronchial tree. Bronchial asthma can be regarded as an exaggerated airway response to different exogenous stimuli. There is indirect evidence that asthmatics form a heterogeneous population characterized by an increased responsiveness in one or more of these airway defense mechanisms. Furthermore, human investigations and animal experiments suggest that both environmental and genetic factors operate at these different levels. The aim of the present paper is to review the evidence that genetic factors control the airway response to exogenous stimuli and correlate these observations with the evidence that genetic factors are involved in the pathogenesis of human bronchial asthma.Reflex bronchoconstriction either by local axon reflexes, or vagal reflexes via the central nervous system;Increase in mucus production and mucociliary clearance;Cough;Inflammation involving different cell types, such as the airway epithelial cells, macrophages, mast cells, and the influx of secondary cells such as neutrophils, eosinophils, and platelets; andImmunological response resulting in a more rapid and a more intense inflammatory and possibly also reflex response.