Phage Display Of Fab Antibody And Study On The Rational Design Of Antibody CDR-H3

Monoclonal antibodies(MAbs)are Y-type immunoglobulins produced by B cells under the stimulation of specific target antigens,and protect the body by interacting with specific antigens.Antibody drugs have a broad therapeutic field and can be used for the treatment of cancer,autoimmune diseases,infectious diseases and metabolic abnormalities,etc.There are more than 80 kinds of antibodies that can be used to treat diseases so far.The first monoclonal antibody approved by the FDA was produced in 1986 through hybridoma technology.Subsequently,a series of monoclonal antibody discovery technologies were developed,mainly include in vitro display,single B cell and transgenic mouse technology.Among them,the in vitro display technology can achieve 100%coverage of the immune repertoire,which provides the possibility for the discovery of antibodies to difficult targets,and has been widely studied by people.Based on the powerful functions of in vitro display technology,this research relies on the phage display platform:1.Established the F(ab’)2 antibody phage display system,and combined with transgenic mouse technology,four humanized F(ab’)2 antibodies against the B7H3 target were screened out.2.Optimized the F(ab’)2 antibody phage display system,established a monovalent F(ab)antibody phage display method,and screened out 52 humanized F(ab)antibodies to the B7H3 target,which greatly improved the Fab type antibody Phage display efficiency.3.Analyze and derive the length-dependent usage rule of DH and JH germline genes when the CDR-H3 region of the antibody is rearranged,and find several major factors that affect the surface area of antibody solvent binding.In summary,this study established a phage display system in the form of antibody F(ab’)2 and F(ab),which provides a standardized method for the phage discovery of other target Fab antibodies.And the antibody CDR-H3 recombination rules summarized in this study provide important theoretical guidance for the design and synthesis of artificial antibody libraries.