Interaction of bacteria with the immune system of Waldeyer's ring in otitis media with effusion

An in vitro assay was used to study the adherence of Haemophilus influenzae (HI) to human nasal, nasopharyngeal, and buccal mucosal cells from patients with otitis media with effusion (OME). Adherence of unencapsulated HI was stronger than that of type b HI. HI adherence to both nasal and nasopharyngeal mucosal cells is stronger than that of buccal ones, indicating the presence of an important route of HI infection from the nose to the nasopharynx in OME. Specific antibodies against outer membrane vesicles (OMV) of HI were also examined using enzyme-linked immunosorbent assay. No significant correlation could be observed between specific secretory IgA or IgG titers and HI adherence to the nasopharyngeal mucosal cells, which suggests that HI adherence to the mucosal cells seems to depend on various factors including the local immunological defense system in OME patients. Anti-OMV IgA antibody producing cells were identified in the adenoid using the three-step immunoperoxidase method. These results suggest that non-typable strains of HI adhere more readily to epithelial cells and consequently are better suited to colonize the nasopharynx or to cause local infections.