In Vitro Models of Infection IHuman Respiratory Tissue Organ Culture

The interaction of bacteria with mucosal surfaces of the respiratory tract is thought to be critical in their pathogenesis. Bacteria must overcome local defenses that include physical barriers such as mucus, beating cilia, and an intact epithelial surface; antibacterial substances such as defensins, secretory immunoglobulin A, and lysozyme; and resident phagocytes. Organ cultures can be used to study the initial interaction of bacteria with the mucosal surface and subsequent events, in particular the effects of bacteria on the structure and function of the respiratory epithelium. Organ cultures have a near-normal ratio of differentiated cell types that maintain their three-dimensional relationships with the extracellular matrix and submucosal tissues, and by incorporating an air interface they closely simulate in vitro the physiological conditions of the respiratory mucosa found in vivo.