ABSTRACT
There is a group of diseases of man, poorly explained and usually chronic, which have in common inflammation occurring in the mucosa. This chapter describes the mechanisms available for immune-mediated injury. It then discusses pathways for initiation of immune hypersensitivity, using as specific examples several major inflammatory diseases with manifestations at the mucosal surface. Contact of intraluminal antigen with selected epithelial cells which cover aggregates of nonprimed lymphocytes is the initial event for induction of a local immune response. Cells capable of carrying out effector functions of the immune response are principally located in the lamina propria, which is the area extending from the single cell epithelium at the lumen to the muscularis mucosa. With most viruses, a replication phase first occurs at the portal of entry on the surface of or within mucosal tissue. Immunopathologically, a lymphoplasmacytic infiltration, is present in the bronchial mucosa of autopsy specimens in patients dying of chronic bronchitis.
