CYTOKERATIN PROFILE OF THE JUNCTIONAL EPITHELIUM IN PARTIALLY ERUPTEDTEETH

This study uses cytokeratins (CK) as markers to investigate the phenot ype of the junctional epithelium (JE) in partially erupted human teeth . The gingival samples, which were clinically healthy, were carefully dissected from the teeth. Cryostat sections were cut for histological staining, immunofluorescence microscopy and gel electrophoresis. Cytok eratins were extracted after microdissection. The basal and suprabasal epithelial cell markers, cytokeratins 4, 5, 13, 14 and 19 were detect ed with specific monoclonal antibodies. They showed that the junctiona l epithelium in erupting teeth has a complex topography. The cytokerat in immunohistochemical profile distinguished between the primary junct ional epithelium (CK 5, 14 and 19 in basal and suprabasal cells and CK 13 faintly stained throughout the suprabasal layers) and the adjacent epithelium that had the same cytokeratin profile as the sulcular epit helium (CK 5, 14 and 19 in basal cells and CK 4 and 13 intensively sta ined in the suprabasal cells). Extraction, two-dimensional electrophor esis and western blotting showed that this transitional JE during erup tion also contained CK 6, 16 and perhaps CK 4. Thus, the JE in eruptin g teeth shows patterns of CK distribution that are very similar to tha t of developing oral epithelia.