Phagocytosis in the nasopharyngeal secretion by cells from the adenoid

The aim of this study was to elucidate whether granulocytes and macrophages in surface secretion on the adenoid emanate from the adenoid and whether t hese cells participate in the control of the nasopharyngeal bacterial flora . Samples of the adenoid and its surface secretion were obtained during ade noidectomy from 12 children with recurrent acute otitis media, secretory ot itis media or enlarged adenoids causing obstruction. Immunochemistry was us ed to examine the location of granulocytes and macrophages in the adenoid a s well as the presence of IgA, IgM, IgG and plasma cells in the secretion. Phagocytosis in the secretion was examined in imprints stained with May-Gru nwald Giemsa. Acridine Orange and Gram staining were used to demonstrate th e presence and location of bacteria in the secretion and mucosa. As a contr ol, surface secretions were obtained from 12 children without any history o f recurrent airway problems. Granulocytes and macrophages were observed in the epithelium of the adenoid and some of these cells penetrated the epithe lial surface. Positive staining for IgA, IgM and IgG was observed in all se cretions. In 10 of 12 children plasma cells were present in the secretion. Bacteria were observed in all imprints. With the exception of I child in ea ch group phagocytosis of bacteria in the surface secretion was demonstrated from imprints in all children. We conclude that granulocytes and macrophag es leave the adenoid and enter the surface secretion, where constant phagoc ytic activity takes place. The spatial relations between mononuclear and po lymorphonuclear cells imply a possible cooperation between these cells in t he overall control of the nasopharyngeal bacterial flora.