Cytokeratin (CK) comprises the intermediate filament cytoskeleton of epithelial cells. Patterns of CK expression can be regarded as a specific marker for epithelial differentiation status. The aim of this study was to identify CK expression on tongues of Korean native goats ranging from 60-day-old fetuses to newborns during prenatal development using immunohistochemistry. The tongues of fetuses were removed from 2- to 4-year-old female Korean native goats by caesarean section performed under general anesthesia. Immunohistochemistry was performed to assess CK expression patterns on developing goat tongues using serial paraffin-embedded sections. Light zones signifying CK immunoreactivity in dorsal lingual epithelia were weakly positive in 60-day-old fetuses. In 90-day-old fetuses, deep areas in dorsal lingual epithelia were strongly positive for CK expression and superficial areas were moderately positive. In 120-day-old fetuses, light zones of lingual epithelia in the vallate papilla were strongly positive for CK expression, whereas ducts of von Ebner’s glands were moderately positive. In neonates, taste buds were positive for CK expression, whereas non-taste epithelial cells and von Ebner’s glands were negative. These findings indicate that goat tongues have different patterns of CK expression during development and provide a morphological basis for studies on the biological mechanism of epithelial differentiation.

Ameloblastomas are benign odontogenic tumor and the most common neoplasm in jaws and they have locally invasive property and high recurrence rate. Four typical subtypes ameloblastomas are plexiform, follicular, granular cell and acanthomatous type, but their developmental states during tumorigenesis are uncertain. And thus authors studied about developing states of four types of ameloblastomas by immunohistochemical staining for cytokeratin 8/18 which was an intermediate filament of epithelial cell origin and for vimentin which was an intermediate filament of mesenchymal cell origin, and then by comparative analyses of the results. Authors selected seven cases for every four types of ameloblastomas, and then performed immunohistochemcial staining for cytkeratin 8/18 and vimentin to all selected specimen by using monoclonal antibodies about cytoleratin 8/18 and vimentin, LSAB(Labelled StreptoAvidin Biotin) reactant and HRP(Horse Radish Peroxidase) system. Labelling indices of cytokeratin 8/18 of plexiform and follicular types of ameloblastomas were significantly high values in the group of ameloblast-like cells and labelling indices of cytokeratin 8/18 of all types of ameloblastoma were high values in the group of transformed cells, but their differences were not significant. Labelling index of vimentin of plexiform ameloblastoma was significantly high value in the group of ameloblast-like cells and others showed comparatively lower values. Labelling index of vimentin of granular cell type of ameloblastoma in the group of transformed cells was significantly high value and others showed comparatively lower values. Consequently the most primitive form of ameloblastoma was plexiform, and more differenciated form was follicular type and granular cell type and acanthomatous type were most differenciated form of ameloblastomas

Glandular odontogenic cyst (GOC) is a rare odontogenic cyst, which shows cystic structures lined by stratified squamous epithelium with various thickness. Glandular duct-like spaces lined by eosinophilic cuboidal or columnar cells constitute the epithelial surface. The purpose of this study was to present 7 cases of GOC retrieved from the files of the Department of Oral Pathology, Seoul National University Dental Hospital and to investigate the immunohistochemical expression of cytokeratins (CKs) in the epithelial components. A total of 7 GOCs were reviewed clinically and radiographically and immunostainning for CK 5, 7, 14, 18 and CK-pan were performed. There were five males and two females aged from 36 to 53 years (mean 45 years). Maxilla was more affected than mandibles (6:1). Radiographically, all cases showed multilocular radiolucencies with well-defined borders. Histologically, lining epithelium of GOC was composed of nonkeratinized stratified epithelial cells with focal plaque-like or whirl pool-like thickenings. Surface epithelial layer contained eosinophilic cuboidal cells or mucous cells. Mucin pools of microcystic areas was also detected in the epithelium. Immunohistochemical study demonstrated that epithelium of GOCs was positively reactive for CK 5 7, 14 and CK-pan with a slight variation in their patterns and there was no reaction for CK 18.