EGFR-CD3 bifunctional antibody and application thereof

The invention provides an EGFR-CD3 bifunctional antibody. The bifunctional antibody comprises two same light chains and two same recombinant heavy chains, wherein the amino acid sequence of each lightchain is as shown in SEQ ID NO. 8, each recombinant heavy chain is formed by connecting an EGFR antibody heavy chain and a single-chain antibody scFv of CD3 protein through a linker sequence; the amino acid sequence of the EGFR antibody heavy chain is as shown in SEQ ID NO. 7; the amino acid sequence of the linker sequence linker is as shown in SEQ ID NO. 9; the amino acid sequence of the single-chain antibody scFv of the CD3 protein is shown as any one of SEQ ID NO.1, SEQ ID NO.2, SEQ ID NO.3, SEQ ID NO.4, SEQ ID NO.5 or SEQ ID NO.6. The EGFR-CD3 bifunctional antibody can be specifically combined with human CD3 protein and EGFR, the immunogenicity of the murine antibody can be reduced, T cells can be effectively activated, the binding of human EGFR and EGFR can be blocked, the bifunctional antibody can be anchor