Viruses as biomaterials

Viruses lacking the capacity to infect mammals exhibit minimal toxicity, good biocompatibility, and well-defined structures. As self-organized biomolecular assemblies, they can be produced from standard biological techniques on a large scale at a low cost. Genetic, chemical, self-assembly, and mineralization techniques have been applied to allow them to display functional peptides or proteins, encapsulate therapeutic drugs and genes, assemble with other materials, and be conjugated with bioactive molecules, enabling them to bear different biochemical properties. So far, a variety of viruses (infecting bacteria, plants, or animals), as well as their particle variants, have been used as biomaterials to advance human disease prevention, diagnosis, and treatment. Specifically, the virus-based biomaterials can serve as multifunctional nanocarriers for targeted therapy, antimicrobial agents for infectious disease treatment, hierarchically structured scaffolds for guiding cellular differentiation and promoting tissue regeneration, versatile platforms for ultrasensitive disease detection, tissue-targeting probes for precision bioimaging, and effective vaccines and immunotherapeutic agents for tackling challenging diseases. This review provides an in-depth discussion of these exciting applications. It also gives an overview of the viruses from materials science perspectives and attempts to correlate the structures, properties, processing, and performance of virus-based biomaterials. It describes the use of virus-based biomaterials for preventing and treating COVID-19 and discusses the challenges and future directions of virus-based biomaterials research. It summarizes the progressive clinical trials of using viruses in humans. With the impressive progress made in the exciting field of virus-based biomaterials, it is clear that viruses are playing key roles in advancing important areas in biomedicine such as early detection and prevention, drug delivery, infectious disease treatment, cancer therapy, nanomedicine, and regenerative medicine.