[Isolation and detection of murine transplantable breast tumor antigen by McAb F36/22]

A transplantable murine breast tumor antigen (called JC tumor) has been recognized by the detection of McAb F36/22 with the method of immunoblotting. JC tumor antigen was isolated by Sepharose-CL-4B, then was purified by McAb F36/22 affinity chromatography. Solid phase RIA detection demonstrated that the specific activity of the antigen which was purified by 188.4 times was 148,000 cpm/mg protein. SDS-PAGE and immunoblot analysis revealed that the tumor antigen possessed a molecular weight of 60kd. Competitive binding RIA indicated that JC tumor antigen inhibited the combining of ductal carcinoma antigen with McAb F36/22. It implied that some groups (antigen determinant) on JC tumor antigen were the same as or similar to those on ductal cancer antigen.