Influence of amino acids on hybridoma cell viability and antibody secretion

It is generally accepted that the phase of cell decline observed in batch culture of mammalian cells is related to exhaustion of medium nutrients (principally glucose and glutamine) and/or to waste products accumulation. In the present paper, we have studied the influence of glutamine on the proliferation of mouse hybridoma cells. We showed that repeated addition of glutamine prolonged the life span of the culture and significantly increased the secretion of monoclonal antibody. Flow cytometry analysis suggests that this effect of glutamine is related to a delay in cell death rather than to a stimulation of proliferation.Addition of glutamine and glucose failed however to prevent the death of the culture. Determinations of amino acid consumption in glutamine-supplemented samples and experiments carried out with complementary sources of amino acids (e.g. tryptose phosphate) strongly suggest that amino acid supply is a critical factor governing cell growth and productivity.