Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 2 1 2003 03 15 25 29 A. Amirzargar S. Feghhi M.H. Nicknam N. Saki 2015 10 01 Otitis media with effusion (OME) is very common in pediatric patients. Immune reactions in serum and middle ear system play roles in the etiology, pathogenesis and prevention of otitis media. Immunologically active antigens interact with immunocompetent cells in the lamina propria of the middle ear to produce a local immune response. In this investigation, 32 sera and 50 middle ear fluid samples from children (ranged 1 to 10 years) with secretory otits media were analyzed for IgA, IgM, IgG, C3 and C4 by single radial immunodiffusion (SRID) and IgE by enzyme linked immunosurbent assay (ELISA) techniques. Our results indicated a highly significant increase in IgA and a decrease in IgM, IgG, IgE, C3 and C4 in secretion as compared to serum concentrations. The ratio of IgA/IgG, a valuable index of local immune response, was higher in the middle ear than in serum. These data support the hypothesis that there is an independent mucosal immune response in the middle ear mucosa to different stimuli. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/30 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/30/30