Transfection with bacterial genes as a marker for cells seeded on vascular flow surfaces

Autologous seeding of vascular grafts has been in use since 1972; however, the fate of seeded cells has never been determined. While short-term retention has been determined by radioactively labeling cells, long-term studies of seeded cells have not been possible due to the lack of an appropriate marker system. We have developed a long-term marker system for endothelial cells by transfecting the cells with bacterial genes that can be detected by fluorescentally-labeled antibodies to these markers. Two bacterial genes, neo and cat both carried by a pSV2 plasmid construct were used to co-transfect cells. Transfects were selected by growth in the presence of G418. Transfected clones were expanded into monolayers that stained positive for cat by fluorescence, and retained the normal cobblestone morphology and factor VIII staining of endothelial cells. By stably transfecting cells with bacterial genes these cells can now be used to seed vascular grafts and follow the long-term fate of seeded cells.