title: A functional antibody mutant with an insertion in the framework region 3 loop of the VH domain: implications for antibody engineering.
abstract: We have studied the effects of a four residue insertion into the FR3 loop of the heavy chain variable region from the anti-NP antibody B1-8. The insertion mutant is obtained as secreted antibody without major defects in biosynthesis, indicating that antibody variable domains can accommodate length variation not only in complementarity determining regions (CDRs), but also in framework region (FR) loops. The B1-8 antigen binding site is not affected by the change in a neighbouring loop. FR3 insertions represent a new method of antibody engineering with a potential to obtain strong antigen binding by designing additional antigen contacting residues.
authors.affiliation: Institut für Genetik, Universität zu Köln, Cologne, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Simon
authors.forename: K
authors.initials: K
authors.lastname: Rajewsky
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D001666:Binding Sites, Antibody; D006241:Haptens / Q000276:immunology; D007143:Immunoglobulin Heavy Chains / Q000737:chemistry* / Q000235:genetics; D007135:Immunoglobulin Variable Region / Q000737:chemistry* / Q000235:genetics; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D009596:Nitrophenols / Q000276:immunology; D010648:Phenylacetates; D011487:Protein Conformation; D015202:Protein Engineering
chemical_list: D006241:Haptens; D007143:Immunoglobulin Heavy Chains; D007135:Immunoglobulin Variable Region; D009596:Nitrophenols; D010648:Phenylacetates; C026242:4-hydroxy-5-nitrophenyl acetic acid