De novo design of immunoglobulin-like domains

Antibodies, and antibody derivatives such as nanobodies, contain immunoglobulin-like (Ig) β-sandwich scaffolds which anchor the hypervariable antigen-binding loops and constitute the largest growing class of drugs. Current engineering strategies for this class of compounds rely on naturally existing Ig frameworks, which can be hard to modify and have limitations in manufacturability, designability and range of action. Here, we develop design rules for the central feature of the Ig fold architecture—the non-local cross-β structure connecting the two β-sheets—and use these to design highly stable Ig domains de novo, confirm their structures through X-ray crystallography, and show they can correctly scaffold functional loops. Our approach opens the door to the design of antibody-like scaffolds with tailored structures and superior biophysical properties.This research was supported by grants from the Spanish Ministry of Science and Innovation (RYC2018-025295-I, EUR2020-112164, and PID2020-120098GA-I00). This study was also supported in part by grants from Spanish and Catalan public and private bodies (grant/fellowship references MCIN/AEI/10.13039/501100011033/PID2019-107725RG-I00, 2017SGR3 and Fundació “La Marató de TV3” 201815). S.R.M. acknowledges grant BES2016-076877 from the Spanish State Agency for Research (MCIN/AEI/10.13039/501100011033) and the European Social Fund “ESF invests in your future”. U.E. was funded by a Beatriu de Pinós post-doctoral fellowship (AGAUR-MSCA COFUND 2018BP00163. J.R.T. was supported by an EMBO postdoctoral fellowship (under grant agreement ALTF 145-2021). J.C.K. was supported by a National Science Foundation Graduate Research Fellowship (grant DGE-1256082). D.B. and T.M.C. acknowledge the Howard Hughes Medical Institute. We thank the Princess Margaret Cancer Centre for funding of the NMR facility. The Structural Genomics Consortium is a registered charity (no: 1097737) that receives funds from Bayer AG, Boehringer Ingelheim, Bristol Myers Squibb, Genentech, Genome Canada through Ontario Genomics Institute [OGI-196], EU/EFPIA/OICR/McGill/KTH/Diamond Innovative Medicines Initiative 2 Joint Undertaking [EUbOPEN grant 875510], Janssen, Merck KGaA (aka EMD in Canada and US), Pfizer and Takeda