Endothelial cell growth supplement: a cell cloning factor that promotes the growth of monoclonal antibody producing hybridoma cells

The efficiency of endothelial cell growth supplement (ECGS), a commercially marketed extract of bovine neural tissue, human endothelial cell supernatant (HECS) derived from freshly isolated endothelial cells, and feeder layers of murine peritoneal cells (PEC), were compared for their ability to support cell fusion, clonal growth, and monoclonal antibody production of murine hybridoma cells. ECGS at 25–100 μg/ml was similar to a 1:5 dilution of HECS in supporting the growth of hybridoma colonies; both ECGS and HECS were superior to PEC feeder cells. Furthermore, hybridomas cloned in ECGS produced anti-lymphotoxin antibodies. The commercial availability and stability of ECGS together with its ability to support hybridoma growth and monoclonal antibody secretion make ECGS a superior growth supplement for the fusion and growth of hybridoma cells in monoclonal antibody production.