Printed in Great Britain AMINO ACID METABOLISM OF MYELOMA CELLS IN CULTURE

The growth of myeloma cells in Leibovitz medium supplemented with 20 % serum was limited by the depletion of glutamine. A simple modification of the Leibovitz medium by increasing the concentrations of glutamine, lysine, isoleucine, leucine, sodium pyruvate, galactose, and vitamins resulted in over 100 % increase in cell growth yield. The total myeloma protein produced by the cells was increased by approximately 90 % in modified Leibovitz media. Analysis of spent culture media for 19 amino acids showed that the concentrations of 8 amino acids were reduced; those of 5 amino acids were increased and the other 6 did not change significantly