Resistance against Ehrlich Ascites Tumor Induced by DEPC-treated Ehrlich Cells

Abstract

The proliferating activity of Ehrlich ascites tumor cells decreased with the increase of the concentration of DEPC per 3×10⁷ cells and disappeared at more than 200 μg. Sixty per cent of the mice immunized with 200 μg DEPC-treated Ehrlich cells twice survived the challenge inoculation. And employment of Freund's complete adjuvant on the immunization increased the survival ratio up to 90_??_100%.
Respiratory activity, trypan blue stainability and agglutination by concanavalin A were investigated. These results and the electronmicroscopical observation suggest that the specific structure of the cell surface must be maintained in the DEPC-treatment in order to display immunogenicity.