Redirecting NK cells mediated tumor cell lysis by a new recombinant bifunctional protein

• Published in: Protein engineering, design and selection Vol. 21; no. 11; pp. 665 - 672
• Main Authors: Germain, Claire, Campigna, Emmanuelle, Salhi, Imed, Morisseau, Sébastien, Navarro-Teulon, Isabelle, Mach, Jean-Pierre, Pèlegrin, André, Robert, Bruno
• Format: Journal Article
• Language: English
• Published: England Oxford University Press 01.11.2008; Oxford Publishing Limited (England); Oxford University Press (OUP)
• Subjects: Animals; bifunctional proteins; Biochemistry, Molecular Biology; Biotechnology; Blotting, Western; Cancer; Cell Death; Cell Death - immunology; Cell Line, Tumor; Computer Science; Cytotoxicity, Immunologic; Electrophoresis, Gel, Two-Dimensional; GPI-Linked Proteins; Humans; Immunology; Intercellular Signaling Peptides and Proteins; Intercellular Signaling Peptides and Proteins - immunology; Killer Cells, Lymphokine-Activated; Killer Cells, Lymphokine-Activated - immunology; Killer Cells, Natural; Killer Cells, Natural - immunology; Killer Cells, Natural - metabolism; Life Sciences; Mice; Minor Histocompatibility Antigens; Minor Histocompatibility Antigens - immunology; natural killer cells; NKG2D; Recombinant Proteins; Recombinant Proteins - immunology; Tumor Cells, Cultured; Tumor Cells, Cultured - metabolism; tumor targeting; ‘knob into hole’ strategy; natural killer cells; bifunctional proteins; NKG2D; tumor targeting; ‘knob into hole’ strategy; Bifunctional proteins/« Knob into hole » strategy/Natural Killer cells/NKG2D/Tumor targeting
• ISSN: 1741-0126; 1741-0134
• DOI: 10.1093/protein/gzn047

Natural killer (NK) cells are at the crossroad between innate and adaptive immunity and play a major role in cancer immunosurveillance. NK cell stimulation depends on a balance between inhibitory and activating receptors, such as the stimulatory lectin-like receptor NKG2D. To redirect NK cells against tumor cells, we designed bifunctional proteins able to specifically bind tumor cells and to induce their lysis by NK cells, after NKG2D engagement. To this aim, we used the ‘knob into hole’ heterodimerization strategy, in which ‘knob’ and ‘hole’ variants were generated by directed mutagenesis within the CH3 domain of human IgG1 Fc fragments fused to an anti-CEA or anti-HER2 scFv or to the H60 murine ligand of NKG2D, respectively. We demonstrated the capacity of the bifunctional proteins produced to specifically coat tumor cells surface with H60 ligand. Most importantly, we demonstrated that these bifunctional proteins were able to induce an NKG2D-dependent and antibody-specific tumor cell lysis by murine NK cells. Overall, the results show the possibility to redirect NK cytotoxicity to tumor cells by a new format of recombinant bispecific antibody, opening the way of potential NK cell-based cancer immunotherapies by specific activation of the NKG2D receptor at the tumor site.