Immunological Defense Mechanisms of the Respiratory System

Abstract

The respiratory system has an enormous epithelial surface exposed to the environment and is in permanent contact with a wide variety of environmental antigens and microorganisms that threaten its performance. The immune system in the lungs and airways must be finely tuned to prevent severe infections and avoid serious inflammation processes that affect gas exchange. Among the defense mechanisms of the respiratory system are innate immunity and adaptive immunity, consisting of cellular and humoral responses that protect and regulate the defenses of the lung parenchyma and the airways. Recent research has shown that there is a bacterial population in the airway mucosa, known as the “respiratory microbiome,” but its behavior in immune homeostasis is unknown.