Molecular basis of a unique tumor antigen of radiation leukemia virus-induced leukemia B6RV2: its relation to MuLV gp70 of xenotropic class.
Hybridomas secreting monoclonal antibodies that reacted with the B6 radiation leukemia virus (RadLV)-induced leukemia B6RV2 were produced by fusion of BALB/c NS-1 myeloma cells with spleen cells from (BALB/c X B6)F1 mice immunized with B6RV2. By direct and absorption analyses with 28 B6 and BALB/c leukemias, the monoclonal antibodies NU7-4 and NU7-99 were shown to react only with B6RV2, indicating that they recognized an individually distinct antigen on B6RV2 that was identified previously with conventional (BALB/c X B6)F1 anti-B6RV2 serum. Another monoclonal antibody, NU1-132, showed relatively restricted reactivity with B6 RadLV leukemias. These three monoclonal antibodies all precipitated material of approximately 80,000 daltons, which is the same size as that precipitated by anti-xenotropic MuLV gp70 serum. Sequential immunoprecipitation analysis revealed that the molecules precipitated by NU7-4 were not removed by pretreatment of NU7-99 or NU1-132 and that the molecules precipitated by NU7-99 were not removed by NU7-4 or NU1-132. The molecules precipitated by NU1-132 were partially removed by pretreatment with NU7-4, but not with NU7-99. The molecules precipitated by these three monoclonal antibodies were removed by pretreatment with anti-xenotropic gp70. These results suggested heterogeneity of the xenotropic MuLV gp70-related molecules expressed on B6RV2 and a possible relation between serologically defined unique tumor antigens and gp70-related molecules.
D000818:Animals; D000911:Antibodies, Monoclonal / Q000032:analysis; D000918:Antibody Specificity; D000937:Antigen-Antibody Reactions; D000954:Antigens, Surface / Q000276:immunology; D000957:Antigens, Viral, Tumor / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D001666:Binding Sites, Antibody; D001667:Binding, Competitive; D004591:Electrophoresis, Polyacrylamide Gel; D009052:Leukemia Virus, Murine / Q000235:genetics / Q000276:immunology; D007953:Leukemia, Radiation-Induced / Q000276:immunology* / Q000382:microbiology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D011233:Precipitin Tests; D011817:Rabbits; D051381:Rats; D012190:Retroviridae / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000954:Antigens, Surface; D000957:Antigens, Viral, Tumor