PMID: 28716900 , Related PDB id: 5TUD

Authors:

Ishchenko A, Wacker D, Kapoor M, Zhang A, Han GW, Basu S, Patel N, Messerschmidt M, Weierstall U, Liu W, Katritch V, Roth BL, Stevens RC, Cherezov V

Title:

Structural insights into the extracellular recognition of the human serotonin 2B receptor by an antibody.

Journal:

Proc Natl Acad Sci U S A. 2017 Aug 1;114(31):8223-8228. doi:, 10.1073/pnas.1700891114. Epub 2017 Jul 17.

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-A resolution structure of a complex between the human 5-hydroxytryptamine 2B (5-HT2B) 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-HT2B 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.