Abnormalities of the tracheobronchial lymph nodes in smokers and subjects with chronic bronchitis: a necropsy study of the distribution of immunoglobulins.

, 397-405. The tracheobronchial lymph nodes obtained at necropsy from small groups of subjects (normal non-smokers, normal smokers, subjects with chronic bronchitis which was incidental to the cause of death, and subjects who had died from long-standing chronic bronchitis) have been examined by immunofluorescent methods to detect immunoglobulin. Cells containing immunoglobulin were seen scattered in the medullary cords and corticomedullary junctions, and also as conglomerates within active germinal centres. Sampling methods on multiple sections were used to count the numbers of single cells containing immunoglobulin (excluding those in germinal centres) and also the numbers of germinal centres containing immunoglobulin. This work has shown that there were fewer plasma cells containing IgA and IgM in fatal' bronchitics than in normal non-smokers, normal smokers, and incidental' bronchitics (IgA p<0·005; IgM p<0·01). These results indicate that the reported depletion of plasma cells found in the airways in a small group of subjects with fatal chronic bronchitis was accompanied by a similar depletion in the regional lymph nodes. It was also found that the numbers of active germinal centres containing immunoglobulin (mostly IgM) were increased in normal smokers, incidental' bronchitics, and fatal' bronchitics, although in these small numbers of subjects the significance of this difference (p<0·05) depends on grouping these subjects together. This suggests that cigarette smoking alters germinal centre activity even in subjects without chronic cough.