Abstract: A fusion protein including a fragment of an anti-mesothelin antibody, an anti-CD3 antibody or an anti-EGFR antibody; a bispecific antibody that is specific to mesothelin and CD3; a trispecific antibody that is specific to mesothelin, CD3 and EGFR are provided. The fusion protein is effective in treating cancer. The bispecific or trispecific antibody can be prepared in a high yield and with high purity, and has excellent tumor killing and growth inhibitory effects, and thus can be effectively used in cancer treatment.

Abstract: The present invention provides anti-CEACAM1 antibodies with improved binding abilities specific to CEACAM1, and a use thereof. Anti-CEACAM1 antibodies according to the present invention exhibit superior binding abilities specific to CEACAM1, and also activate the anti-cancer immune functions of cytotoxic T cells and natural killer cells, and thus, each one of them can be effectively used as an anti-cancer agent and a composition for treating cancer.

Abstract: The present invention provides anti-CEACAM1 antibodies with improved binding abilities specific to CEACAM1, and a use thereof. Anti-CEACAM1 antibodies according to the present invention exhibit superior binding abilities specific to CEACAM1, and also activate the anti-cancer immune functions of cytotoxic T cells and natural killer cells, and thus, each one of them can be effectively used as an anti-cancer agent and a composition for treating cancer.

Abstract: A framework fragment derived from a chicken antibody, in which an amino acid at a particular position is replaced by cysteine, a heavy chain variable region or a light chain variable region including the framework fragment, or an antibody including the heavy chain variable region or the light chain variable region does not induce or prevents formation of disulfide bonds between antibody molecules while maintaining activity and reactivity of the antibody. The antibody introduced with cysteine or an antigen-binding fragment thereof easily binds with a conjugation compound such as a chemotherapeutic drug, an enzyme, an aptamer, a toxin, an affinity ligand, or a detection label, thereby being applied to various fields for diagnosis or treatment of diseases.

Abstract: A framework fragment derived from a chicken antibody, in which an amino acid at a particular position is replaced by cysteine, a heavy chain variable region or a light chain variable region including the framework fragment, or an antibody including the heavy chain variable region or the light chain variable region does not induce or prevents formation of disulfide bonds between antibody molecules while maintaining activity and reactivity of the antibody. The antibody introduced with cysteine or an antigen-binding fragment thereof easily binds with a conjugation compound such as a chemotherapeutic drug, an enzyme, an aptamer, a toxin, an affinity ligand, or a detection label, thereby being applied to various fields for diagnosis or treatment of diseases.