Cell proliferation and metabolism of Ehrlich ascites tumor cells grown in chemically defined albumin medium for several passages.

Cell proliferation, cell cycle distribution, viability, uptake of alpha-aminoisobutytic acid, cyclo leucine and 2-deoxyglucose as well as DNA, RNA and protein synthesis of Ehrlich ascites tumor cells grown in suspension culture over three passages in serum free nutrient medium supplemented with 1-2% bovine serum albumin) Cohn fraction V, Serva) were measured and compared to cells grown in medium supplemented with 15% horse serum. At the end of the fourth passage in vitro, that is the third passage in serum free albumin medium, the growth of the cells is reduced to about 10% of the controls, accumulation of the cells in G2 is delayed and the number of dead cells rises to 30%. The transport rates of alpha-aminoisobutyric acid and of 2-deoxyglucose slowly decrease while the uptake of cycloleucine shows a more complex behaviour in albumin medium. Incorporation of thymidine and leucine into the cells corresponds to the growth rate, while the incorporation of uridine in normal as well as in albumin medium exhibits different pattern. The present experiments demonstrate, that it may be possible to preserve this cells in a fairly "physiological" state during two passages in albumin medium.