De novo design of integrin α5β1 modulating proteins to enhance biomaterial properties

Integrin alpha5beta1 is crucial for cell attachment and migration in development and tissue regeneration, and alpha5beta1 binding proteins can have considerable utility in regenerative medicine and next-generation therapeutics. We use computational protein design to create de novo alpha5beta1-specific modulating miniprotein binders, called NeoNectins, that bind to and stabilize the open state of alpha5beta1. When immobilized onto titanium surfaces and throughout 3D hydrogels, the NeoNectins outperform native fibronectin (FN) and RGD peptides in enhancing cell attachment and spreading, and NeoNectin-grafted titanium implants outperformed FN- and RGD-grafted implants in animal models in promoting tissue integration and bone growth. NeoNectins should be broadly applicable for tissue engineering and biomedicine.