Specific dual-targeting antibody for resisting EGFRvIII and CD3, minicircle DNA containing dual-targeting antibody expression cassette and applications

Abstract

The invention provides a specific dual-targeting antibody, a method thereof and applications. The specific dual-targeting antibody has a first antigen binding domain which binds to human CD3 specifically and a second antigen binding domain which binds to an EGFRvIII antigen specifically, can recognize and bind to the EGFRvIII antigen and EGFRvIII over-expressed cancer cells specifically, and can bind to a T cell receptor (TCR), wherein cancers comprise a liver cancer, other EGFRvIII positive tumor diseases and the like; and the specific dual-targeting antibody mediates a T cell to play a killing role, thus EGFRvIII infection is removed, and the specific dual-targeting antibody has great application value in diagnosis and treatment, prevention, and detection of EGFRvIII related diseases. The invention also provides a minicircle DNA which has a nucleotide sequence for coding the specific dual-targeting antibody. The invention provides the specific dual-targeting antibody and the minicircle DNA, wherein the specific dual-targeting antibody and the minicircle DNA can be used for preparing an antibody pharmaceutical composition or preparing an EGFRvIII positive tumor cell diagnostic reagent.

Description

technical field [0001] The invention relates to the fields of biomedicine and diagnosis and treatment, in particular to an anti-EGFRvIII and CD3 specific dual-targeting antibody, a microcircle DNA containing an expression cassette of the dual-targeting antibody, and applications thereof. Background technique [0002] The epidermal growth factor receptor type III mutant (EGFRvIII) is the deletion of exons 2-7 of the extracellular region of EGFR (801bp, 267aa), resulting in the fusion of exons 1 and 8, and a new glycine is produced at the fusion site, Therefore, a new antigenic determinant is formed outside the membrane, and its expression rate is very high in malignant tumors such as glioma, breast cancer, non-small cell lung cancer, prostate cancer, and ovarian cancer, and this mutant is a tumor process products, only appear in tumor cells. EGFRvIII lacks most of the ligand-binding regions of the extracellular region of EGFR, and can undergo autophosphorylation, constitutiv...

AI Technical Summary

Problems solved by technology

The antibody can only bind to EGFRvIII antigen and EGFRvIII-positive cells, but cannot bind to T cells and cannot mediate T cell killing; it can only be targeted and killed by ADCC (antibody-dependent cell-mediated cytotoxicity) or CDC (complement-dependent cytotoxicity) EGFRvIII antigen-positive tumor cells also have host-versus-graft reaction when they are used for human therapy, the main related papers (Cancer Res. 61.)

[0006] (2) Recombinant monoclonal antibody recombinant antibody anti-EGFRvIII (Rab DMvIII), developed by Stanford University, connects the antibody variable region with amino acid chains, and then connects it with the Fc segment of human IgG, and passes through Knobs-into-holes Transformation, increased affinity and improved humanization, eliminated most of the mouse sequence, the antibody can bind EGFRvIII antigen and EGFRvIII positive cells, but still can not bind T cells, can not mediate T cell killing; only through ADCC Or CDC can target and kill EGFRvIII antigen-positive tumor cells, but the clinical efficacy is not yet clear, the main related papers (BMC Biotechnol.2010Oct 7; 10:72.)

[0007] (3) Mouse-derived monoclonal antibody CH12 (anti-EGFRvIII), an antibody developed in China, developed by Shanghai Cancer Inst, Shanghai Yijie Biotech Company, is currently in phase II clinical trials, and can only bind to EGFRvIII antigen and express positive EGFRvIII cells, cannot bind T cells, and cannot mediate T cell killing; can only target and kill EGFRvIII antigen-positive tumor cells through ADCC or CDC

[0008] There is currently no approved EGFRvIII×CD3 dual-targeting antibody on the market

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