Adherence of Haemophilus influenzae to middle ear mucosa injured by killed H. influenzae.
Repetitive acute otitis media is due to recurrent bacterial infection of middle ear superimposed on chronic otitis media with effusion. Endotoxin, one of the constituents of Haemophilus influenzae, is present in some cases in the middle ear effusion of otitis media with effusion and has been demonstrated experimentally to damage the middle ear mucosa. The aim of this study was to determine the effect of killed H. influenzae on the adherence of H. influenzae and H. parainfluenzae to the middle ear epithelial cells. The numbers of adherent organisms per epithelial cell in ears inoculated previously with killed H. influenzae or with normal saline (0.9% NaCl) were compared. Prior middle ear inoculation of killed H. influenzae enhanced the adherence of H. influenzae to middle ear epithelial cells, but it had little effect on the adherence of H. parainfluenzae. H. influenzae adhered to middle ear epithelial cells in greater numbers than H. parainfluenzae. Results demonstrate that a middle ear pathogen adheres to middle ear epithelial cells presumably damaged by killed H. influenzae, whereas a non-pathogen does not. These findings might partly explain the increased susceptibility of an ear with chronic otitis media with effusion to recurrent infection with H. influenzae.
Hando
S
S
Department of Otolaryngology, Niigata University School of Medicine, Japan.
Nonomura
N
N
Niijima
H
H
Fujioka
O
O
Nakano
Y
Y
D000818:Animals; D002478:Cells, Cultured; D004432:Ear, Middle / Q000166:cytology* / Q000276:immunology; D004731:Endotoxins / Q000276:immunology; D004847:Epithelial Cells; D004848:Epithelium / Q000276:immunology; D006168:Guinea Pigs; D006192:Haemophilus Infections / Q000276:immunology*; D006193:Haemophilus influenzae / Q000166:cytology* / Q000276:immunology; D008297:Male; D008856:Microscopy, Fluorescence; D009092:Mucous Membrane / Q000166:cytology / Q000276:immunology; D010034:Otitis Media with Effusion / Q000276:immunology; D015164:Vaccines, Inactivated / Q000276:immunology
D004731:Endotoxins; D015164:Vaccines, Inactivated