Studies on Fluid Media for the Cultivation of Mouse Ascites Tumour Cells In Vitro

ASCITES tumours in experimental animals are essentially almost pure populations of suspended tumour cells multiplying in peritoneal exudate. Amoebocytes and shed peritoneal cells are usually present in relatively low numbers. The suitability of these tumours for quantitative studies on malignant cells has long been realised. As a measure of chemotherapeutic activity, Lettre (1941, 1950) used differences in the survival times of control and treated mice injected with uniform volumes of ascites tumour fluid and reported that increases in body weight of inoculated mice were proportional to increases in numbers of the tumour cells. This latter relation was shown by Klein (1951) to be valid onlly for inoculations with certain numbers of tumour cells. The value of Ehrlich ascites tumour cells for quantitative studies on growth and biochemistry has been discussed in detail by Klein (1950, 1951). These particular advantages include ease of serial sampling, low incidence of necrotic cells, uniform nutritive conditions and distribution of cells in the exudate, and direct action of agents on the tumour cells. In vitro cultivation of ascites tumour cells in fluid media offers additional advantages. It affords more precise control of the extracellular medium and environment, and direct microscopic observation of the tumour cells in situ. A fluid medium supporting multiplication of Ehrlich ascites tumour cells in vitro has therefore been devised.