Efficient and stable retroviral transfection of ovine endothelial cells with green fluorescent protein for cardiovascular tissue engineering

To determine whether cellular components of tissue-engineered cardiovascular structures are derived from cells harvested and seeded onto an acellular scaffold, or from cells originating from surrounding tissue (e.g., proximal and distal anastomosis), cellular retroviral transfection with green fluorescent protein (GFP) was used. Ovine endothelial cells (ECs) were transfected with a Moloney murine leukemia virus (Mo-MuLV)-based retroviral vector expressing GFP. Transfection was evaluated by fluorescence microscopy and fluorescence-activated cell sorting. The rate of transfection of the primary cells was 33.4% for ECs, 48 hours after transfection. Stable transfection could be observed for at least 25 subsequent passages. Retroviral transfection with GFP enables stable and reliable long-term labeling of ovine ECs. This approach might offer an attractive pathway to study tissue development, with emphasis on distinguishing between cellular components initially seeded onto a construct and those occurring as a result of cell ingrowth from surrounding tissue.