C: Keratins as markers of differentiated taste cells of the rat. Differentiation 1995, 58:341–349. doi:10.1186/1749-8104-9-21 Cite this article as: Koudelka et al.: Genetic dissection of TrkB activated signalling pathways required for specific aspects of

Abstract. Cytokeratins in taste buds were immunocyto-chemically evaluated with monoclonal antibodies. In each of six different epithelial sites in the rat oral cavity, intragemmal cells of taste buds were immunoreactive for keratin polypeptides 8, 18, and 19, as well as for keratin 7, which has not been previously reported in taste buds. Keratin- 18-like immunoreactivity was present in fewer than half of the intragemmal cells, whereas all intragem-ma1 cells were immunopositive for keratins 7, 8, and 19. Apart from some salivary duct cells, no other cells in the tongue were immunoreactive for any of these four kera-tins. Morphological and immunocytochemical profiles indicate that taste buds are islets of simple epithelium embedded in an expanse of stratified squamous epitheli-um. These simple epithelial cells and their keratins are nerve-dependent, since denervatiorf eliminated all four keratins and replaced elongated taste cells of the vallate papilla with stratified squamous epithelium. We con-clude that antibodies against keratins 7, 8, or 19 are use-ful markers for intragemmal cells in studies of taste bud development, degeneration, regeneration, turnover and tissue culture