Effect of Inhibitor of TNF-alpha on Lipopolysaccharide-induced Otitis Media with Effusion / 대한이비인후과학회지

ABSTRACT

BACKGROUND AND OBJECTIVES: Tumor necrosis factor (TNF)-alpha, a potent inflammatory mediator, seems to be important in the pathogenesis of otitis media with effusion (OME). The purpose of this study is to determine the effect of TNF-alpha antagonist on the outcome of experimental OME induced by lipopolysaccharide (LPS) in rats. MATERIALS AND METHODS: Otitis media was induced by injecting 40 microliter (1 mg/ml) of Pseudomonas aeruginosa LPS transtympanically in one group of rats. Other groups were treated with LPS after transtympanic injection of TNF-alphaantagonist, soluble TNF receptor type I (sTNF RI), 10 microliter (0.1 microgram/ microliter), and with saline as controls. Twelve hours after inoculation of LPS, otoscopic examination and aspiration of middle ear effusion (MEE) were done. The temporal bones in each group were harvested and examined histopathologically and vascular permeability (VP) of middle ear (ME) mucosa was measured by Evans blue vital dye technique. RESULTS: The percentage of MEE developing in the LPS and LPS with sTNF RI (combination) groups were 90% and 0%, respectively. Histopathologic examination of ME revealed less inflammation and mucosal thickening, and a significant decrease in the middle ear VP in the combination group when compared with the LPS group. CONCLUSION: Transtympanic administration of TNF-alphaantagonist appears to suppress the development of LPS-induced OME. This study suggests that TNF-alpha antagonist along with antibiotics may have an adjunctive role in the future treatment of MEE.