Immunohistochemical study on cytokeratin expression on developing tongue in Korean native goats (Capra hircus)

Abstract

Cytokeratin (CK) comprises the intermediate filament cytoskeleton of epithelial cells. Patterns of CK expression can be regarded as a specific marker for epithelial differ- entiation 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 develop- ment using immunohistochemistry. The tongues of fetuses were removed from 2- to 4-year-old female Korean native goats by caesarean section performed under general anes- thesia. 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 posi- tive. 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 posi- tive. 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 develop- ment and provide a morphological basis for studies on the biological mechanism of epithelial differentiation.