[Effect of environmental factors on the defense system of the respiratory tract]

Respiratory system due to its enormous surface is particularly prone to be penetrated by various exogenous factors. Therefore, this system is equipped with numerous local, specific and unspecific, cellular and humoral immunological mechanisms. This system includes: BALT (bronchial ++adeno-lymphatic tissue) producing secretory immunoglobulins, ciliary system, mucus which provides an extracellular surface for immunoglobulins, lysozyne, interferon, lactoferrin, and complement system activities. Moreover, alveolar macrophages, surfactant, neuropeptides, and inflammatory processes constitute other components of the whole defense system. A complex interactions increasing its efficiency take place between particular components. Unfavourable environmental factors attack this system in several ways. The most important are: recurrent bacterial and viral respiratory infections, air pollution, tobacco smoke, and unfavourable climate and microclimate.