Epidermal Growth Factor and Transforming Growth Factor-α in Middle Ear Effusion

Abstract

Epidermal growth factor (EGF) and transforming growth factor-α (TGF-α) promote the differentiation and proliferation of epithelia as well as the proliferation and chemotaxis of fibroblasts. Additionally, EGF promotes wound healing in tissues composed largely of epithelial cells and fibroblasts. We hypothesized that EGF and TGF-α 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 children with otitis media. As an initial test of this hypothesis, EGF and TGF-α concentrations were measured in 82 middle ear effusions of children undergoing tympanostomy tube placement. EGF was present in 45% of these effusions, and TGF-α was present in 6%. The mean concentration ± SEM values for EGF and TGF-α were 19 ± 7.6 and 3.7 ± 7.9 pg/mL, respectively. In addition, neutrophils, macrophages, and lymphocytes in middle ear effusions stained for EGF by immunocytochemistry. We conclude that growth factors are frequently present in middle ear effusions of children with otitis media