Cultivation and characterisation of primary and subcultured equine keratinocytes.

We describe the establishment and characterisation of equine keratinocyte cultures with maintenance of a high proliferative capacity up to the second passage. Improved attachment and growth were obtained by seeding primary cells on equine feeder layers. Subcultured keratinocytes showed optimal growth when seeded on collagen type I. The proliferation rate of cells on this substrate exceeded that seen for cells seeded on equine feeder layers. By immunohistochemistry, epithelial origin and state of differentiation of the equine keratinocytes were determined. They expressed keratin and desmoplakin I/II, but lacked keratin 10. Electron microscopy revealed typical features of cultured keratinocytes. Purity of keratinocyte cultures was determined by vimentin staining. This is the first report on the establishment of equine keratinocytes derived from lip epithelium. It forms the basis to study equine keratinocyte biology and the pathogenesis of epidermal diseases. Since wound healing represents a severe problem in equine dermatology, our data may be essential for the establishment of new and improved therapy.