title: Restoring nervous system structure and function using tissue engineered living scaffolds.
abstract: Neural tissue engineering is premised on the integration of engineered living tissue with the host nervous system to directly restore lost function or to augment regenerative capacity following nervous system injury or neurodegenerative disease. Disconnection of axon pathways - the long-distance fibers connecting specialized regions of the central nervous system or relaying peripheral signals - is a common feature of many neurological disorders and injury. However, functional axonal regeneration rarely occurs due to extreme distances to targets, absence of directed guidance, and the presence of inhibitory factors in the central nervous system, resulting in devastating effects on cognitive and sensorimotor function. To address this need, we are pursuing multiple strategies using tissue engineered "living scaffolds", which are preformed three-dimensional constructs consisting of living neural cells in a defined, often anisotropic architecture. Living scaffolds are designed to restore function by serving as a living labeled pathway for targeted axonal regeneration - mimicking key developmental mechanisms- or by restoring lost neural circuitry via direct replacement of neurons and axonal tracts. We are currently utilizing preformed living scaffolds consisting of neuronal clusters spanned by long axonal tracts as regenerative bridges to facilitate long-distance axonal regeneration and for targeted neurosurgical reconstruction of local circuits in the brain. Although there are formidable challenges in preclinical and clinical advancement, these living tissue engineered constructs represent a promising strategy to facilitate nervous system repair and functional recovery.
authors.affiliation: Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA ; Center for Neurotrauma, Neurodegeneration, and Restoration, Philadelphia Veterans Affairs Medical Center, Philadelphia, PA, USA.
authors.forename: Laura A
authors.initials: LA
authors.lastname: Struzyna
authors.affiliation: Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA ; Center for Neurotrauma, Neurodegeneration, and Restoration, Philadelphia Veterans Affairs Medical Center, Philadelphia, PA, USA.
authors.forename: James P
authors.initials: JP
authors.lastname: Harris
authors.affiliation: Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA ; School of Biomedical Engineering, Drexel University, Philadelphia, PA, USA.
authors.forename: Kritika S
authors.initials: KS
authors.lastname: Katiyar
authors.affiliation: Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA ; Center for Neurotrauma, Neurodegeneration, and Restoration, Philadelphia Veterans Affairs Medical Center, Philadelphia, PA, USA.
authors.forename: H Isaac
authors.initials: HI
authors.lastname: Chen
authors.affiliation: Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA ; Center for Neurotrauma, Neurodegeneration, and Restoration, Philadelphia Veterans Affairs Medical Center, Philadelphia, PA, USA.
authors.forename: D Kacy
authors.initials: DK
authors.lastname: Cullen
keywords: axon pathfinding; biomaterials; cell migration; cell transplant; living scaffolds; neural tissue engineering; neurodegeneration; neurotrauma; regeneration