Immunohistochemical Study of the Distribution of Transcriptional Factor Sox2 in the Lingual Epithelium of Human Embryos and Fetuses

Transcriptional factor Sox2 is one of the key factors in the development of mammal sensory system. Sox2 expression was revealed in rodent developing taste buds, while the role of this factor in morphogenesis of human taste system still remains unstudied.

The aim of investigation was to study the character of a transcriptional factor Sox2 distribution in the lingual epithelium of human embryos and fetuses.

Materials and Methods. We carried out an immunohistochemical study of lingual epithelium of 28 human fetuses and embryos from 6^th to 21^st week of prenatal development.

Results. Immunopositive reaction to Sox2 was revealed in lingual epithelial cells starting from the 10^th week of development and in all later stages. The greatest number of Sox2 immunopositive nuclei was localized in a basal layer of lingual epithelium and in epithelial evaginations associated with papillae morphogenesis. Since the 15^th week of prenatal development Sox2 expression level increased in apical parts of taste papillae and in taste bud cells. The comparison of immunopositive nuclei distribution with the main morphogenetic events in lingual epithelium of human fetus showed Sox2 to regulate the morphogenesis of human lingual papillae and at early stages (before the 10^th week) and not participate in differentiation of taste bud cells.

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Kurtova A.I. Immunohistochemical Study of the Distribution of Transcriptional Factor Sox2 in the Lingual Epithelium of Human Embryos and Fetuses. Sovremennye tehnologii v medicine 2014; 6(1): 23