Genetic construction and characterization of a fusion protein consisting of a chimeric F(ab') with specificity for carcinomas and human IL-2.
A genetic construct was created incorporating gene fragments encoding the H chain V region of the human carcinoma specific antibody L6, the CH1 domain of human IgG1, a linker region, and human IL-2. This construct was cotransfected with a chimeric L6 L chain construct into the murine myeloma cell line Ag8.653 for expression. First round clones produced the fusion protein at an estimated 5 to 10 micrograms/ml based on idiotypic reactivity. Dual binding activity was demonstrated through specific interaction with the L6 Ag on human tumor cells and the IL-2R on activated human T cells. The IL-2 portion of the molecule was shown to support the growth of the IL-2-dependent T cell line CTLL2, and the qualitative nature of the IL-2 signal was found to be the same as rIL-2 with respect to induction of tyrosine-phosphorylation of intracellular protein substrates. Tumor cells coated with the fusion protein were shown to cause T cell proliferation and the presence of the fusion protein was found to enhance cell-mediated destruction of human tumor cells.
Fell
H P
HP
Oncogen Division, Bristol-Myers Squibb Pharmaceutical Research Institute, Seattle, WA 98121.
Gayle
M A
MA
Grosmaire
L
L
Ledbetter
J A
JA
D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000235:genetics; D000912:Antibodies, Neoplasm / Q000235:genetics*; D001483:Base Sequence; D002277:Carcinoma / Q000276:immunology*; D003001:Cloning, Molecular; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000235:genetics; D007376:Interleukin-2 / Q000235:genetics*; D008213:Lymphocyte Activation; D008969:Molecular Sequence Data; D019000:Phosphotyrosine; D015375:Receptors, Interleukin-2 / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism*; D015183:Restriction Mapping; D015398:Signal Transduction; D013601:T-Lymphocytes / Q000378:metabolism; D014443:Tyrosine / Q000031:analogs & derivatives / Q000378:metabolism
D000911:Antibodies, Monoclonal; D000912:Antibodies, Neoplasm; D007140:Immunoglobulin Fab Fragments; D007376:Interleukin-2; D015375:Receptors, Interleukin-2; D011993:Recombinant Fusion Proteins; D019000:Phosphotyrosine; D014443:Tyrosine