Studies on cell surface antigens of mouse leukemic and normal lymphocytes. II. Relationships between mammary leukemia, gross virus related and major histocompatibility antigens on L1210 leukemic lymphocytes.

The presence of ML antigen on leukemia L1210 cells was confirmed by different procedures. In addition, by applying appropriate absorptions and blocking techniques combined with ferritin labelled antibodies in electron microscopy (EM), the independent localization of ML antigen and murine leukemia virus Gross (MuLV-Gross) cellular antigen on L1210 cells was demonstrated. The ferritin labeled antigenic sites appeared to be free from budding viral particles. In further studies the 3M KCI extracts of L1210 leukemia cells purified by polyacrylamide gel electrophoresis (PAGE) and the antigenic material from leukemia L1210 cells purified by affinity chromatography were characterized. Their identity was verified by anti ML-sera. Using the modified lyso-strip method, the presence of ML antigen and H-2K and H-2D gene products on independent molecules on the surface of L1210 cells was shown. In addition, in preparative polyacrylamide gel electrophoresis (PAGE) of 3M KCL extracts of L1210 cells, ML and H-2d antigenic products were found in separate fractions.