Crystal structures of immunoglobulin Fc heterodimers reveal the molecular basis for heterodimer formation.
Choi, H.J., Seok, S.H., Kim, Y.J., Seo, M.D., Kim, Y.S.(2015) Mol Immunol 65: 377-383
- PubMed: 25743157 
- DOI: https://doi.org/10.1016/j.molimm.2015.02.017
- Primary Citation of Related Structures:  
4X98, 4X99 - PubMed Abstract: 
We determined the X-ray crystal structure of an immunoglobulin fragment crystallizable (Fc) heterodimer, EW-RVT, at a resolution of 2.5Å and found that the designed asymmetric interaction residues located in the heterodimeric CH3 interface favor Fc heterodimer formation. We further generated an inter-CH3 disulfide-bonded heterodimeric Fc variant, EW-RVT(S-S), which exhibited improved heterodimer formation and thermodynamic stability compared with the parent EW-RVT variant. The crystal structure of EW-RVTS-S superimposed very closely with the wild-type Fc structure. Our results provide the detailed structure of heterodimeric Fc scaffolds, which will be useful for the generation of immunoglobulin G (IgG)-like bispecific antibodies.
Organizational Affiliation: 
Department of Molecular Science and Technology, Ajou University, Suwon 443-749, Republic of Korea.