RESUMO
The expression of cytokeratin and vimentin is described in 10 pleomorphic adenomas and in normal salivary gland tissue using an immunoperoxidase method. From our observations we can conclude the following 1] In tumour tissue the basal layer of tubulo - ductal structures and the spindle cells in masses showed positive staining with monoclonal cytokeratin [KG 8.13] and vimentin antibodies. The luminal cell layer was positive to cytokeratin antibody. 2] The distribution of cytokeratin and vimentin in pleomorphic adenoma was similar to that present in normal salivary gland tissue. 3] The basal cell in tubulo-ductal structures expressing both epithelial and mesenchymal cell markers seem to represent a population of stem cells capable of differentiation along epithelial and mesenchymal lines of differentiation. These cells can have an important role in the histogenesis of pleomorphic adenoma