Local immune system of nasal nucosa in inflammation. IgA distribution and secretory activity

The local immune system of human mucosa (inferior turbinates and nasal polyps) from 53 humans with chronic inflammation was studied by examining the distribution and secretory activity of IgA using an immunofluorescent technique. Diffuse fluorescence for IgA was observed throughout the connective tissue ground substance in every nasal turbinate and nasal polyp. In mucosa with mild inflammatory changes, most IgA seemed to be produced locally by IgA-producing plasma cells. However, in severely inflamed nasal mucosa, including nasal polyps, plasma cells were relatively fewer in number and the distribution of IgA generally corresponded to the pattern of fibrin deposition. Secretory activity of IgA in the glandular cells of nasal turbinates was well retained. Only in dilated glandular ductules in nasal polyps was the secretory activity impaired.