MONOCLONAL ANTIBODIES AGAINST MURINE LEUKEMIA VIRUSES - IDENTIFICATION OF 6 ANTIGENIC DETERMINANTS ON THE P15(E) AND GP70 ENVELOPE PROTEINS

Hybrid cells that produced monoclonal antibodies against the envelope proteins of murine leukemia virus (MuLV) were prepared by the polyethylene glycol-mediated fusion of a mouse myeloma cell line with lymphocytes from mice immunized with allogeneic MuLV-producing leukemia cells. Twenty-three independent cell lines were cloned and inoculated into syngeneic mice for the production of ascites fluids that contained high-titered (20-75 mg/ml) monoclonal antibodies. Six serologically distinct specificities were detected when these ascites fluids were tested on a broad panel of MuLV and non-murine retra iruses. Prototype cell lines producing monoclonal antibodies that were representative of each pattern of reaction were selected for further study. In immune precipitation assays each of the prototype antibodies reacted with viral envelope proteins; three of these identified antigenic determinants on p15(E), while three others identified antigenic determinants on gp70. The p15(E) antigenic determinants were shared by a diverse panel of MuLV. One of these p15(E) antigenic determinants was also found in feline leukemia virus. The gp70 antigenic determinants, on the other hand, had a more restricted distribution and were found in only selected isolates of MuLV. © 1979.