title: The injured brain interacts reciprocally with neural stem cells supported by scaffolds to reconstitute lost tissue.
abstract: Hypoxic-ischemic injury is a prototype for insults characterized by extensive tissue loss. Seeding neural stem cells (NSCs) onto a polymer scaffold that was subsequently implanted into the infarction cavities of mouse brains injured by hypoxia-ischemia allowed us to observe the multiple reciprocal interactions that spontaneously ensue between NSCs and the extensively damaged brain: parenchymal loss was dramatically reduced, an intricate meshwork of many highly arborized neurites of both host- and donor-derived neurons emerged, and some anatomical connections appeared to be reconstituted. The NSC-scaffold complex altered the trajectory and complexity of host cortical neurites. Reciprocally, donor-derived neurons were seemingly capable of directed, target-appropriate neurite outgrowth (extending axons to the opposite hemisphere) without specific external instruction, induction, or genetic manipulation of host brain or donor cells. These "biobridges" appeared to unveil or augment a constitutive reparative response by facilitating a series of reciprocal interactions between NSC and host, including promoting neuronal differentiation, enhancing the elaboration of neural processes, fostering the re-formation of cortical tissue, and promoting connectivity. Inflammation and scarring were also reduced, facilitating reconstitution.
authors.affiliation: Department of Pediatrics, Pharmacology, and Brain, Korea 21 Project for Medical Sciences, Yonsei University College of Medicine, Seoul, 120-752, Korea.
authors.forename: Kook In
authors.initials: KI
authors.lastname: Park
authors.forename: Yang D
authors.initials: YD
authors.lastname: Teng
authors.forename: Evan Y
authors.initials: EY
authors.lastname: Snyder
mesh_terms: D000818:Animals; D001672:Biocompatible Materials; D001921:Brain / Q000473:pathology / Q000601:surgery; D002999:Clone Cells; D020925:Hypoxia-Ischemia, Brain / Q000150:complications / Q000473:pathology* / Q000628:therapy*; D051379:Mice; D009410:Nerve Degeneration / Q000209:etiology / Q000473:pathology / Q000601:surgery; D009416:Nerve Regeneration; D009434:Neural Pathways / Q000473:pathology; D009474:Neurons / Q000473:pathology*; D011100:Polyglycolic Acid; D019736:Prostheses and Implants; D033581:Stem Cell Transplantation; D013234:Stem Cells / Q000473:pathology*; D013784:Textiles
chemical_list: D001672:Biocompatible Materials; D011100:Polyglycolic Acid