Immunologic and histologic observations in reovirus-induced otitis media in the mouse

The goals of this study were to develop a mouse model for virally induced o titis media, and to study the immune response to infection. Intranasal inoc ulation of mice by reovirus was used to induce otitis media. Immunohistoche mical evidence for the presence of reovirus in the nasopharynx, eustachian tubes, and middle ears and the amount of infiltrating B-cells and T-cells i n those sites were serially evaluated by painlessly sacrificing animals ove r a 21-day period. Reovirus antigen was detected in the middle ear mucosa b y day 4 in 75% of infected animals, and histologic evidence for otitis medi a was found in 54% of all infected animals. A significant increase in B-cel ls in the nasopharynx and eustachian tubes was noted 7 to 10 days following infection. The number of infiltrating T-cells did not vary significantly f rom that in the control animals at any of the sites. These results provide a basis for further investigations of the immune response in otitis media.