Genetically engineered liquid-crystalline viral films for directing neural cell growth

Designing biomimetic matrices with precisely controlled structural organization that provides biochemical and physical cues to regulate cell behavior is critical for the development of tissue-regenerating materials. We have developed novel liquid-crystalline film matrices made from genetically engineered M13 bacteriophages (viruses) that exhibit the ability to control and guide cell behavior for tissue-regenerating applications. To facilitate adhesion between the viruses and cells, 2700 copies of the M13 major coat protein were genetically engineered to display integrin-binding peptides (RGD). The resulting nanofiber-like viruses displaying RGD motifs were biocompatible with neuronal cells and could be self-assembled to form long-range-ordered liquid-crystalline matrices by a simple shearing method. The resulting aligned structures were able to dictate the direction of cell growth. Future use of these virus-based materials for regenerating target tissues in vivo would provide great opportunities for various tissue therapies.