TTFFLUOR HUVEC are Green fluorescent primary HUVEC dells which have been developed through transient transfection with a tGFP expression vector expressing the green fluorescent protein gene sequences as free cytoplasmid protein. TTFFLOUR HUVEC are intended to be used in cell-based assay applications and provide consistent levels of tGFP expression during two passages, simplifying the interpretation of results. Endothelial cell processes such as tube formation, can be studied in vitro using the TTFLOUR HUVEC cells.