Demonstration of interleukin 6 in middle ear effusions.

In response to infection in the middle ear, inflammatory cells produce cytokines--potent regulators and mediators of the immune response. In an earlier study, we demonstrated that levels of the cytokine interleukin 1 were higher in middle-ear effusions from younger children, while levels of the cytokine tumor necrosis factor were higher in middle-ear effusions from older children and in those requiring tympanostomy on multiple occasions. In this study, we evaluated middle-ear effusions for levels of the cytokine interleukin 6. Activities of interleukin 6 include stimulation of bone erosion and production of antibodies and fever. Using an enzyme-linked immunosorbent assay system, significant levels of interleukin 6 (greater than 0.2 pg/mL) were found in 14 (36%) of 39 middle-ear effusions from 25 children with otitis media with effusion. The mean (+/- SE) level of interleukin 6 in middle-ear effusions was 173.9 +/- 74.7 pg/mg of total protein. Like interleukin 1, levels of interleukin 6 were higher in younger children. Tumor necrosis factor may be an important regulator of the local immune response in the middle-ear cleft during persistence of otitis media with effusion, while interleukin 1 and interleukin 6 may be important regulators during the early stages of otitis media with effusion.