Aim： reducing immunogenicity, decrease MW, increase permeability

抗体药物常见作用机制包括：配体-受体相互作用的破坏；通过抗体依赖性细胞毒性、补体依赖性细胞毒性和抗体依赖性细胞吞噬，清除靶细胞；双特异性抗体T细胞接合器；通过增强内化和降解下调受体；靶向给药

Chimeric antibody

The gene of variable region of H and L chain of mouse antibody conjugated with the constant region of human Ig，

the recombinant gene is re--expressed on CHO or other cells to expressed on CHO or other cells to produce produce chimeric Antibody.

Reshaping antibody

small molecule antibody

(1) Fab antibody：VH+CH1

(2) FV Ab：VH+VL

(3)single chain Ab：VH-Linker-VL

(4)single domain Ab：VH or VL

Diabody structure

Antibody fusion protein

combining antigen-binding region with bioactive protein

CD4-Fcγ, G-CSF-Fc.