Nanostructured biopolymer-microglial cell implants for spinal cord/CNS repair

Abstract

There are no clinically effective therapies for repair of spinal cord damage and other injuries to CNS tissues. More than 250,000 are affected, with 10,000 new injuries annually in the U.S. and about 50% are paraplegic or quadriplegic. Annual health care costs exceed $10 billion. Tissue engineering concepts using various polymer scaffolds and nerve tissue growth factors have been problematic clinically. Reported here are results from a unique multidisciplinary program at the University of Florida involving investigators from the College of Engineering and the College of Medicine. Research has encompassed the synthesis, characterization, and in vivo evaluation (including noninvasive high field MRI) of biodegradable implants comprising composite structures of microglial cells in a porous alginate and/or DNA matrix with phospholipid nanosurface modification. Microglia are the natural CNS repair cells. The strategy employed in this study was to develop composite cell-polymer structures designed to facilitate the complex sequencing of biosynthesis and regulation of natural neurotophic factors which enable the CNS repair processes and stimulate the growth of neural networks. In a rat spinal cord injury model, effective wound healing and neural regeneration was demonstrated without cystic cavity complications. Preclinical studies are aimed at optimizing cell-polymer compositions, implant design, and surgical protocols for such implants to minimize scarring and enhance functional neuromuscular recovery. © 2009 Springer Berlin Heidelberg.