Structural insights into the extracellular recognition of the human serotonin 2B receptor by an antibody.
Ishchenko, A., Wacker, D., Kapoor, M., Zhang, A., Han, G.W., Basu, S., Patel, N., Messerschmidt, M., Weierstall, U., Liu, W., Katritch, V., Roth, B.L., Stevens, R.C., Cherezov, V.(2017) Proc Natl Acad Sci U S A 114: 8223-8228
- PubMed: 28716900 
- DOI: https://doi.org/10.1073/pnas.1700891114
- Primary Citation of Related Structures:  
5TUD - PubMed Abstract: 
Monoclonal antibodies provide an attractive alternative to small-molecule therapies for a wide range of diseases. Given the importance of G protein-coupled receptors (GPCRs) as pharmaceutical targets, there has been an immense interest in developing therapeutic monoclonal antibodies that act on GPCRs. Here we present the 3.0-? resolution structure of a complex between the human 5-hydroxytryptamine 2B (5-HT 2B ) receptor and an antibody Fab fragment bound to the extracellular side of the receptor, determined by serial femtosecond crystallography with an X-ray free-electron laser. The antibody binds to a 3D epitope of the receptor that includes all three extracellular loops. The 5-HT 2B receptor is captured in a well-defined active-like state, most likely stabilized by the crystal lattice. The structure of the complex sheds light on the mechanism of selectivity in extracellular recognition of GPCRs by monoclonal antibodies.
Organizational Affiliation: 
Department of Chemistry, Bridge Institute, University of Southern California, Los Angeles, CA 90089.