B3(Fv)-PE38KDEL, a single-chain immunotoxin that causes complete regression of a human carcinoma in mice.
The genes encoding the heavy- and light-chain Fv regions of the monoclonal murine antibody B3, which recognizes a carbohydrate antigen on the surface of many human carcinomas, were cloned by PCR techniques and used to generate single-chain immunotoxins containing Pseudomonas exotoxin (PE). The light and heavy chains were connected by a flexible linker to form a single-chain antigen-binding protein, B3(Fv), which was in turn fused to truncated forms of PE lacking the cell-binding domain. The single-chain Fv and two different B3(Fv) immunotoxins, B3(Fv)-PE40 and B3(Fv)-PE38KDEL, were expressed in Escherichia coli and the single-chain immunotoxins were purified to near homogeneity. Both recombinant immunotoxins were shown to be cytotoxic specifically to carcinoma cell lines that express the B3 antigen on their surface; B3(Fv)-PE38KDEL was significantly more active. Furthermore, intravenous administration of B3(Fv)-PE38KDEL caused complete regression of human epidermoid carcinomas growing subcutaneously in immunodeficient mice.
Laboratory of Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892.
U
U
Brinkmann
L H
LH
Pai
D J
DJ
FitzGerald
M
M
Willingham
I
I
Pastan
D036002:ADP Ribose Transferases; D000595:Amino Acid Sequence; D000818:Animals; D000912:Antibodies, Neoplasm / Q000235:genetics*; D000951:Antigens, Neoplasm / Q000276:immunology*; D001427:Bacterial Toxins; D001483:Base Sequence; D002294:Carcinoma, Squamous Cell / Q000628:therapy*; D002470:Cell Survival; D003001:Cloning, Molecular; D005098:Exotoxins / Q000008:administration & dosage* / Q000235:genetics; D005803:Genes, Immunoglobulin; D007135:Immunoglobulin Variable Region / Q000235:genetics; D000922:Immunotoxins / Q000378:metabolism / Q000633:toxicity; D051379:Mice; D008819:Mice, Nude; D008969:Molecular Sequence Data; D009368:Neoplasm Transplantation; D009841:Oligonucleotides / Q000737:chemistry; D016133:Polymerase Chain Reaction; D014176:Protein Biosynthesis; D011550:Pseudomonas aeruginosa; D011993:Recombinant Fusion Proteins; D013329:Structure-Activity Relationship; D037521:Virulence Factors; D000097668:Pseudomonas aeruginosa Exotoxin A
D036002:ADP Ribose Transferases; D000912:Antibodies, Neoplasm; D000951:Antigens, Neoplasm; D001427:Bacterial Toxins; D005098:Exotoxins; D007135:Immunoglobulin Variable Region; D000922:Immunotoxins; D009841:Oligonucleotides; D011993:Recombinant Fusion Proteins; D037521:Virulence Factors; D000097668:Pseudomonas aeruginosa Exotoxin A