Antibody response to a solubilized tumor-associated membrane antigen (TAMA) from the murine lewis lung tumor

A tumor-associated membrane antigen (TAMA) has been solubilized from the C57B1/6 murine Lewis lung tumor using the detergent Triton X100. Xenoantiserum prepared in rabbits was used to identify this tumor antigen in Triton extracts by double immunodiffusion in agar. The antigen was partially purified using a combination of DEAE and Sephadex G200 chromatography followed by sucrose gradient isoelectric focusing. Isoelectric focusing also showed the antigen to have a pI at pH 4.7. Sodium dodecylsulfate polyacrylamide gel electrophoresis indicated the antigen to be of 37,000 molecular weight. The ¹²⁵I protein A antibody-binding assay was used to further characterize the specificity of the antigen using rabbit antisera to the Triton extract. The same assay system also detected a specific antitumor humoral response in syngeneic mice immunized with the Triton extract.