Nanotransfection-based Cell Reprogramming to Drive Bone Revascularization in a Novel Mouse Model of Autogenous Cranioplasty - Project Summary/ Abstract Traumatic brain injury (TBI) is a major cause of death and disability, with an estimated 1.5 million Americans receiving medical care each year for TBI. Patients with severe TBI require a decompressive craniectomy (DC), which is a lifesaving surgery to remove a large segment of the skull and relieve elevated pressure in the brain. The bone is then cryopreserved until brain swelling resolves (typically weeks to months), after which it is replaced in a cranioplasty surgery. Pathophysiological processes, including impaired revascularization of the cryopreserved bone, can lead to complete reconstruction failure, neurological deterioration, prolonged hospital stays, and increased economic burden. The foundation for this proposal is based on recent mouse model studies demonstrating that nonviral, nanotransfection based vasculogenic cell reprogramming can drive revascularization of the brain in ischemic stroke, as well as peripheral nerves in sciatic nerve injury, with improved functional outcomes in both instances. The current studies propose to utilize this technology for a new application: calvarial bone revascularization. Specifically, the aims of this proposal are to 1) Characterize and further develop a novel mouse model of autogenous cryopreserved cranioplasty after TBI and DC; and 2) Utilize fibroblasts nanotransfected with the transcription factors Etv2, Foxc2, and Fli1 (EFF-TNT) to induce vasculogenesis in autogenous cryopreserved calvarial bone in mice. Together, these studies will provide a mechanistic understanding of cryopreserved calvarial bone healing after decompressive craniectomy and explore an innovative approach to optimize healing. This proposal presents a five-year mentored career development program that will provide critical mentorship and position the candidate to transition from a primarily clinical role to an independent surgeon-scientist. The candidate is currently a tenure-track Assistant Professor at the Ohio State University. The outlined proposal builds on her previous clinical and research experience in calvarial reconstruction by integrating two new domains of expertise represented by her primary mentor Dr. Paco Herson and mentorship team: 1) Characterization of a novel animal model for studying pathophysiological processes in calvarial bone healing and testing therapeutic approaches (Dr. Ching-Chang Ko), and 2) utilizing an innovative, nanotransfection cell- based approach to revascularize bone and improve healing (Dr. Daniel Gallego-Perez). She is uniquely poised to carry out the proposed studies based on her training and background. She is firmly committed to a career as a translational surgeon-scientist and will have additional mentorship from Dr. Clara Lee to guide this aspect of her career trajectory. Completion of this comprehensive training plan will provide the candidate with the skills and experience necessary to become a leading independent investigator specializing in calvarial bone reconstruction after decompressive craniectomy.
