Expression of immunoglobulin heavy chain-ricin A chain fusions in mammalian cells.
Mammalian cell lines were transfected with antibody heavy (H) chain-ricin A chain gene fusions in attempts to assemble a recombinant immunotoxin. We found that a light chain-secreting mouse plasmacytoma cell line can be transfected stably with such a chimaeric gene, but only if the ricin A chain portion is disarmed by genetic means prior to transfection; if not, stable transfection appears to select for genetic inactivation of the transfected gene. Co-expression of an antibody heavy chain-ricin A chain fusion with light chain in non-lymphoid cells results in cell death. We conclude that the ricin A chain moiety retains biological activity precluding the expression of biologically active antibody-ricin A chain fusion proteins in mammalian cells.
Spooner
R A
RA
Department of Clinical Oncology, Royal Postgraduate Medical School, Hammersmith Hospital, London, U.K.
Allen
D J
DJ
Epenetos
A A
AA
Lord
J M
JM
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015139:Blotting, Southern; D002460:Cell Line; D003001:Cloning, Molecular; D004247:DNA; D007143:Immunoglobulin Heavy Chains / Q000096:biosynthesis* / Q000276:immunology; D000922:Immunotoxins / Q000096:biosynthesis* / Q000276:immunology; D008322:Mammals; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D010957:Plasmids; D016133:Polymerase Chain Reaction; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000276:immunology; D012276:Ricin / Q000096:biosynthesis* / Q000276:immunology; D014162:Transfection; D014407:Tumor Cells, Cultured
D007143:Immunoglobulin Heavy Chains; D000922:Immunotoxins; D011994:Recombinant Proteins; D004247:DNA; D012276:Ricin