Targeting gamma interferon to tumor cells by a genetically engineered fusion protein secreted from myeloma cells.
The construction, synthesis and expression of a genetically engineered bifunctional antibody/cytokine fusion protein is described. To target IFN-tau to tumor cells, recombinant antibody techniques were used to construct a RM4/IFN-tau fusion protein containing the chimeric anti-tumor F(ab')2 (RM4) and the IFN-tau moiety. The recombinant cDNA of IFN-tau was linked to 3 prime end of the chimeric heavy-chain gene fragment (M4) containing the VH, the CH1 and the hinge region to form the fused heavy-chain gene fragment M4-IFN-tau. Transfection of the M4-IFN-tau gene fragment into a myeloma derived cell line VKCK which produced the chimeric light-chain of the same antibody, allowed the transfectant secreting the bifunctional fusion protein RM4/IFN-tau. The RM4/IFN-tau was purified by the affinity chromatography. Our data showed that the RM4/IFN-tau retained the TAG72 antigen-binding reactivity as well as the IFN-tau activity as measured in ELISA, FACS analysis of cell-surface TAG72 expression, immunohistochemical study, and up-regulation of cell-surface expression of CEA, HLA class I and class II antigens. Therefore, the bifunctional fusion protein RM4/IFN-tau may prove to be useful in targeting biological effects of the IFN-tau to tumor cells and in this way to stimulate the immune destruction of tumor cells.
Xiang
J
J
Saskatoon Cancer Center, Department of Microbiology, University of Saskatchewan, Canada.
Qi
Y
Y
Cook
D
D
Moyana
T
T
D000230:Adenocarcinoma / Q000276:immunology; D000595:Amino Acid Sequence; D000912:Antibodies, Neoplasm / Q000235:genetics / Q000276:immunology*; D000951:Antigens, Neoplasm / Q000276:immunology; D003001:Cloning, Molecular; D003110:Colonic Neoplasms / Q000276:immunology; D016889:Endometrial Neoplasms / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005822:Genetic Vectors; D006023:Glycoproteins / Q000276:immunology; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000235:genetics / Q000276:immunology*; D007150:Immunohistochemistry; D007371:Interferon-gamma / Q000235:genetics / Q000276:immunology*; D008969:Molecular Sequence Data; D009101:Multiple Myeloma / Q000235:genetics / Q000276:immunology; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology*; D014407:Tumor Cells, Cultured / Q000276:immunology
D000912:Antibodies, Neoplasm; D000951:Antigens, Neoplasm; D006023:Glycoproteins; D007140:Immunoglobulin Fab Fragments; D011993:Recombinant Fusion Proteins; C047052:tumor-associated antigen 72; D007371:Interferon-gamma