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E Dabelsteen

Publications and source records attributed to E Dabelsteen.

187 records · Page 11Linked to original sources

Thomsen-Friedenreich (T) antigen as marker of myoepithelial and basal cells in the parotid gland, pleomorphic adenomas and adenoid cystic carcinomas. An immunohistological comparison between T and sialosyl-T antigens, alpha-smooth muscle actin and cytokeratin 14.

Controversy centres on the role and identification of myoepithelial (MEC) and basal cells in salivary gland tumours, and recent studies suggest that both basal cells and myoepithelial cells participate in the formation of salivary gland tumours. We have correlated the expression of different well-known markers of normal MEC/basal cells (i.e. alpha-smooth muscle actin and cytokeratin 14) with T (Thomsen-Friedenreich) antigen and its sialylated derivative: sialosyl-T antigen,) in 17 normal parotid glands and in two tumour types with MEC participation (i.e pleomorphic adenomas (PA) and adenoid cystic carcinomas (ACC)) using immunohistology with well-defined monoclonal antibodies (MAbs). Paraffin-embedded/fresh frozen tissue sections were studied from 33/17 patients with PA and 15/7 patients with ACC. In normal parotid tissue coexpression of alpha-smooth muscle actin, cytokeratin 14, T and sialosyl-T antigens was found in all MEC and in some of the basal cells lining striated ducts. The remaining basal cells exclusively expressed cytokeratin 14, T and sialosyl-T antigens. In the tumours, cells believed to be modified myoepithelial cells showed two different staining patterns: 1) Coexpression of alpha-smooth muscle actin, cytokeratin 14, T and sialosyl-T antigens, and 2) Coexpression of cytokeratin 14, T and sialosyl-T antigens, but no alpha-smooth muscle actin. The epithelial ductular structures in the tumours showed aberrant expression of cytokeratin 14, T and sialosyl-T antigens, and cytokeratin 14 was the only marker of cells in solid undifferentiated areas of adenoid cystic carcinomas. Our study supports the view, that modified "myoepithelial" cells in the tumours consist of a mixture of basal cells and myoepithelial cells. None of the investigated structures was in itself an ideal marker in the identification of MEC/basal cells. The cells can be identified by a combination of markers (i.e. cytokeratin 14, alpha-smooth-muscle actin, T and sialosyl-T antigens).

Actins↗

Experimental studies of cholesteatomas. In vivo studies on epithelial-mesenchymal interaction and bone resorption in the immunodeficient "nude" mouse.

A model for studying different aspects of human cholesteatomas in vivo and in the immunodeficient "nude" mouse is described. Epithelial-mesenchymal interaction was studied in human cholesteatoma membranes, transplanted to the flank region. Findings of cystic lesions lined by stratified keratinizing epithelium were frequent, and the connective tissue reaction was weak. Furthermore, human cholesteatoma membranes were transplanted into the middle ear cavity of 'nude' mice. After 21-28 days, bone resorption was found in the labyrinthine capsule, but not always with signs of inflammation.

Adolescent↗

Simple mucins (T, sialosyl-T, Tn and sialosyl-Tn) are not diagnostic for malignant breast lesions.

Immunohistochemical study of the distribution of carbohydrate core-structures on O-linked glycoproteins (T, sialosyl-T, Tn and sialosyl-Tn) was performed using specific monoclonal antibodies on 148 primary breast lesions, including 10 normal breast tissues, 16 benign lesions and 122 invasive carcinomas (79 localized and 43 metastatic lesions). T antigen, not observed in normal breast tissue, was present in 31% of the benign lesions and in some cases of morphologically normal epithelium adjacent to tumor cells, compatible with altered glycosylation being an early event. Sialosyl-T (s-T) antigen was present in all cases of normal epithelium and in 81% of the benign lesions. Both Tn and sialosyl-Tn (s-Tn) antigen were present in normal breast lesions. Both Tn and sialosyl-Tn (s-Tn) antigen were present in normal breast tissue (30%) and benign lesions (31% and 19%). In the malignant lesions, 20% were positive for T antigen, 82% for s-T antigen, 66% for Tn antigen and 22% for s-Tn antigen. The staining pattern was nearly identical for carcinomas with and without lymph node metastases. In conclusion, immunostaining for simple mucins does not permit a clear distinction between benign and malignant breast lesions.

Antibodies, Monoclonal↗