A soluble single-chain T-cell receptor IL-2 fusion protein retains MHC-restricted peptide specificity and IL-2 bioactivity.
Antibody-based targeted immunotherapy has shown promise as an approach to treat cancer. However, many known tumor-associated antigens are not expressed as integral membrane proteins and cannot be utilized as targets for antibody-based therapeutics. In order to expand the limited target range of antibodies, we have constructed a soluble single-chain T-cell receptor (TCR) fusion protein designated 264scTCR/IL-2. This fusion protein is comprised of a three-domain HLA-A2-restricted TCR specific for a peptide epitope of the human p53 tumor suppressor protein, which is overexpressed in a broad range of human malignancies. The 264scTCR/IL-2 fusion protein has been expressed at high levels in mammalian cells, and milligram quantities have been purified. MHC-restricted antigen-specific binding properties are maintained in the single-chain, three-domain TCR portion of the fusion protein, and the IL-2 portion retains bioactivity similar to that of free recombinant IL-2. Moreover, this fusion protein is capable of conjugating target and effector cells, remains intact in the blood and substantially increases the half life of the IL-2 portion of the molecule. Finally, the 264scTCR/IL-2 fusion protein can be used to stain tumor cells and is capable of reducing lung metastases in an experimental model of metastasis. Thus, TCR-based fusion proteins may provide a novel class of targeted immunotherapeutics for cancer.
Card
Kimberlyn F
KF
Altor BioScience Corporation, 2810 N. Commerce Parkway, Miramar, FL 33025, USA.
Price-Schiavi
Shari A
SA
Liu
Bai
B
Thomson
Elizabeth
E
Nieves
Esperanza
E
Belmont
Heather
H
Builes
Janette
J
Jiao
Jin-an
JA
Hernandez
Javier
J
Weidanz
Jon
J
Sherman
Linda
L
Francis
John L
JL
Amirkhosravi
Ali
A
Wong
Hing C
HC
D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000938:Antigen-Presenting Cells / Q000276:immunology; D005260:Female; D015789:HLA-A2 Antigen / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D007376:Interleukin-2 / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D008175:Lung Neoplasms / Q000276:immunology / Q000517:prevention & control* / Q000556:secondary; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000276:immunology / Q000378:metabolism*; D011948:Receptors, Antigen, T-Cell / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000276:immunology / Q000378:metabolism*; D014407:Tumor Cells, Cultured; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000276:immunology / Q000378:metabolism
D000911:Antibodies, Monoclonal; D015789:HLA-A2 Antigen; D007376:Interleukin-2; D010446:Peptide Fragments; D011948:Receptors, Antigen, T-Cell; D011993:Recombinant Fusion Proteins; D016159:Tumor Suppressor Protein p53