Tales of biomaterials, molecules, and cells for repairing and treating brain dysfunction

Current therapies have limited or no capacity to restore lost function, slow ongoing neurodegeneration, or promote regeneration following damage to the brain. Biomaterials are playing an increasingly important role in the development of novel, potentially efficacious approaches to brain treatment and repair. Programmable biomaterials enable and augment the targeted delivery of drugs into the brain and allow cell/tissue transplants to be effectively delivered and integrate into the brain, to serve as delivery vehicles for therapeutic proteins, and rebuild damaged circuits. Similarly, biomaterials are being increasingly used to recapitulate specific aspects of brain niches to promote regeneration and/or repair damaged neuronal pathways with stem cell therapies. Many of these approaches are gaining momentum because nanotechnology allows greater control over material-cell interactions that induce specific developmental processes and cellular responses including differentiation, migration, and outgrowth. This review discusses the state of the art and new directions in the convergence of biomaterial science, drug delivery, and stem cell biology in the treatment of degenerative and malignant brain diseases.