Epidermal growth factor and transforming growth factor-alpha in middle eareffusion

Epidermal growth factor (EGF) and transforming growth factor-alpha (TGF-alp ha) promote the differentiation and proliferation of epithelia as well as t he proliferation and chemotaxis of fibroblasts. Additionally, EGF promotes wound healing in tissues composed largely of epithelial cells and fibroblas ts. We hypothesized that EGF and TGF-alpha regulate the differentiation and proliferation of the epithelial lining and the migration and proliferation of fibroblasts in the subepithelial space of the middle ear mucosa in chil dren with otitis media. As an initial test of this hypothesis, EGF and TGF- alpha concentrations were measured in 82 middle ear effusions of children u ndergoing tympanostomy tube placement. EGF was present in 45% of these effu sions, and TGF-alpha was present in 6%. The mean concentration +/- SEM valu es for EGF and TGF-alpha were 19 +/- 7.6 and 3.7 +/- 7.9 pg/ml, respectivel y. In addition, neutrophils, macrophages, and lymphocytes in middle ear eff usions stained for EGF by immunocytochemistry. We conclude that growth fact ors are frequently present in middle ear effusions of children with otitis media.