Lymphocyte circulation to the middle ear.

The movement of lymphocytes into the tympanic cavity was studied during an immune response in the middle ear. Sensitized lymphocytes obtained from peripheral blood, peripheral lymph nodes, spleen, mesenteric lymph nodes and Peyer's patches of strain-13 inbred guinea pigs were labelled with 51Cr and injected intravenously into strain-13 recipients undergoing a middle ear immune response. The middle ears and immune organs of the recipients were assayed for radioactivity to detect the infiltration of labelled cells. Lymphocytes from all sources entered the middle ear mucosa in response to immune stimulation at equal levels, suggesting that the middle ear is seeded non-specifically by circulating lymphocytes in response to antigenic stimulation. The infiltration of lymphocytes of mucosal origin into the middle ear cavity is consistent with the participation of the middle ear in a defense system in common with other mucosal organs.