The structure of dual-variable-domain immunoglobulin molecules alone and bound to antigen

Abstract

A dual-specific, tetravalent immunoglobulin G-like molecule, termed dual variable domain immunoglobulin (DVD-Ig™), is engineered to block two targets. Flexibility modulates Fc receptor and complement binding, but could result in undesirable cross-linking of surface antigens and downstream signaling. Understanding the flexibility of parental mAbs is important for designing and retaining functionality of DVD-Ig™ molecules. The architecture and dynamics of a DVD-Ig™ molecule and its parental mAbs was examined using single particle electron microscopy. Hinge angles measured for the DVD-Ig™ molecule were similar to the inner antigen parental mAb. The outer binding domain of the DVD-Ig™ molecule was highly mobile and three-dimensional (3D) analysis showed binding of inner antigen caused the outer domain to fold out of the plane with a major morphological change. Docking high-resolution X-ray structures into the 3D electron microscopy map supports the extraordinary domain flexibility observed in the DVD-Ig™ molecule allowing antigen binding with minimal steric hindrance.

Keywords: :

• immunoglobulin
• bispecific antibodies
• transmission electron microscopy
• dual variable domain molecules
• structure
• crystallography

Disclosure of Potential Conflicts of Interest

The design, study conduct and financial support for the study were provided by AbbVie (formerly Abbott) and from NIH NCATS grant 5R44TR000182 to Joyce Sung and Bridget Carragher. AbbVie participated in the interpretation of data, review and approval of the publication; all authors contributed to the development of the publication and maintained control over the final content. Bridget Carragher and Joyce Sung received funding support from AbbVie. Ivan Correia, Randall Burton, Czeslaw Radziejewski, Tariq Ghayur and Clarissa Jakob are AbbVie employees and may hold AbbVie stock and/or options

Acknowledgments

The authors are grateful to Gary Welch, George Avgerinos and Jochen Salfeld for their support.

Supplemental Material

Supplemental materials may be found here:

http://www.landesbioscience.com/journals/mabs/article/24258