Eosinophil-derived transforming growth factors (TGF-alpha and TGF-beta(1))in human periradicular lesions

Inflammatory mediators of periradicular lesions ave poorly understood. Tran sforming growth factors-alpha and -beta(1), (TGF-alpha and TGF-beta(1)) hav e been linked with the cellular processes for both soft and hard tissue wou nd healing. The purpose of this study is to demonstrate the cellular source s of TGF-alpha and TGF-beta(1) mRNA and protein in periapical lesions by in situ hybridization and immunohistochemistry. Nine periapical granulomas an d nine periapical cysts were examined. TGF-alpha mRNA and protein were not detectable in the granulomas examined. However, eosinophils surrounding the periapical cysts demonstrated both TGF-alpha mRNA and protein. The vast ma jority of eosinophils present in the periapical granulomas and cysts also d emonstrated TGF-beta(1) mRNA and protein. Other cells producing TGF-beta(1) were lymphocytes, fibroblasts, and monocytes. The presence of wound repair cytokines, such as TGF-alpha and TGF-beta(1), suggests a mechanism by whic h the host inflammatory response may participate in the repair and remodeli ng of periapical tissues.