George T Gallagher

Transforming growth factor-alpha (TGF-alpha) and TGF-beta 1 have been proposed as important regulators of processes critical to successful wound healing. Although various cells present in wounds represent potential sources of either TGF-alpha and/or TGF-beta, including macrophages, neutrophils, keratinocytes, fibroblasts, and endothelial cells, we recently identified eosinophils as an additional potential source of these cytokines. We therefore used in situ hybridization and ...

Transforming growth factor alpha (TGF-alpha) is a pleuripotential cytokine with diverse biological effects, including the ability to influence the proliferation of normal cells or neoplastic epithelial cells. Eosinophils are a subset of granulocytes that normally enter the peripheral tissues, particularly those beneath gastrointestinal, respiratory, and urogenital epithelium, where they reside in close proximity to the epithelial elements. In this study, we demonstrate that the great ...

Using hamster as an oral wound healing model, we examined eosinophils and their expression of transforming growth factor-alpha (TGF-alpha) and transforming growth factor-beta 1 (TGF-beta 1). Oral wounds healed approximately two times faster than their cutaneous counterparts. Eosinophils infiltrated prominently into oral wounds; however, unlike the dual expression of TGF-alpha and TGF-beta 1 in skin wounds, oral wound-associated eosinophils expressed TGF-beta 1, but not TGF-alpha. Because ...

Aberrant expression of TGF-alpha is associated with human malignant oral epithelium. Experiments were initiated to determine the cellular sources of transforming growth factor-alpha (TGF-alpha) in human oral cancer. Ten freshly resected human oral cancers and four specimens of normal human oral epithelium were studied by in situ hybridization and immunohistochemistry. Tissues were probed with 35S-labeled sense and antisense riboprobes to (i) human TGF-alpha (hTGF-alpha), (ii) human ...

Carcinoma associated fibroblasts (CAFs) form the main constituents of tumor stroma and play an important role in tumor growth and invasion. The presence of CAFs is a strong predictor of poor prognosis of head and neck squamous cell carcinoma. Despite significant progress in determining the role of CAFs in tumor progression, the mechanisms contributing to their activation remain poorly characterized, in part due to fibroblast heterogeneity and the scarcity of reliable fibroblast surface ...

Inflammatory mediators of periradicular lesions are poorly understood. Transforming growth factors-alpha and -beta 1 (TGF-alpha and TGF-beta 1) have been linked with the cellular processes for both soft and hard tissue wound healing. The purpose of this study is to demonstrate the cellular sources of TGF-alpha and TGF-beta 1 mRNA and protein in periapical lesions by in situ hybridization and immunohistochemistry. Nine periapical granulomas and nine periapical cysts were examined. ...

We recently demonstrated that eosinophils infiltrate prominently into cutaneous wounds in the Syrian hamster and represent a source of transforming growth factor-alpha and transforming growth factor-beta. In this study, we assessed the role of the eosinophil and eosinophil-derived transforming growth factors in human oral ulcers that exhibit delayed healing, descriptively termed traumatic ulcerative granuloma with stromal eosinophilia. Our aim was to determine whether eosinophils, which ...

Sclerosing polycystic adenosis (SPCA) of the salivary gland is a rarely encountered lesion of uncertain pathogenesis that shares histologic features with sclerosing adenosis and fibrocystic disease of the mammary gland. To date, fewer than 40 cases of SPCA have been reported in the literature; all but one have arisen in the major salivary glands. We report 3 cases of SPCA involving minor salivary glands and discuss the characteristic histopathologic features of SPCA , which include a ...

Large scale gene expression profiling was carried out on laser capture microdissected (LCM) tumor and normal oral epithelial cells and analysed on high-density oligonucleotide microarrays. About 600 genes were found to be oral cancer associated. These oral cancer associated genes include oncogenes, tumor suppressors, transcription factors, xenobiotic enzymes, metastatic proteins, differentiation markers, and genes that have not been implicated in oral cancer. The database created ...

Epidermal growth factor (EGF) and transforming growth factor-alpha (TGF-alpha) are known to promote the healing of epithelial wounds. Eosinophils are present in healing wounds and have recently been shown to be capable of producing TGF-alpha. This investigation was done to determine if eosinophils infiltrated into healing wounds are capable of expressing this cytokine. Using the rabbit cutaneous open wound model, the study found that the eosinophil is one of the predominant cell types in ...

Wound healing is critical to the survival of the species after injury. Using hamsters as an experimental model, we have shown that eosinophils infiltrate prominently into skin wounds and that they express transforming growth factor-alpha and -beta 1 mRNAs and proteins. We hypothesized that eosinophils are important in wound healing. As no animal model is genetically deficient in eosinophils, a suitable way to test the hypothesis is to selectively reduce and/or deplete the influx of ...