OMEC-II - A NEW OVINE MAMMARY EPITHELIAL-CELL LINE

We have established three independent ovine mammary epithelial cell li nes which arose from primary cultures of ovine mammary epithelial cell s by spontaneous immortalization. One of them, OMEC II, was characteri sed in greater detail. The cells grow rapidly on plastic dishes in med ium containing 10% FCS without any requirement for additional growth f actors or hormones. Immunofluorescence staining of this cell line show ed expression of cytokeratin (46 kDa) and ZO-1, a tight-junction assoc iated protein, but negative immunostaining for an anti-vimentin antibo dy. In confluent cell monolayers 'domes' became visible indicating the development of a polarised phenotype and the ability of directed secr etion. When grown in collagen gels typical ducts with end-buds were ob served. Treatment with lactogenic hormones increased the frequency of dome formation, but no expression of beta-lactoglobulin was found. To our knowledge this is the first report on an ovine mammary epithelial cell line. ((C) Elsevier, Paris).