Failure of Schwann cells as supporting cells for adult neural progenitor cell grafts in the acutely injured spinal cord

Cell Tissue Res. 2007 Jan;327(1):1-13. doi: 10.1007/s00441-006-0252-y. Epub 2006 Aug 29.

Abstract

Adult neural progenitor cells (NPC) co-grafted with fibroblasts replace cystic lesion defects and promote cell-contact-mediated axonal regeneration in the acutely injured spinal cord. Fibroblasts are required as a platform to maintain NPC within the lesion; however, they are suspected to create an inhospitable milieu for regenerating central nervous system (CNS) axons. Therefore, we thought to replace fibroblasts by primary Schwann cells, which might serve as a superior scaffold to maintain NPC within the lesion and might further enhance axon regrowth and remyelination following spinal cord injury. Adult rats underwent a cervical dorsal column transection immediately followed by transplantation of either NPC/Schwann cell or NPC/Schwann cell/fibroblast co-grafts. Animals receiving Schwann cell or fibroblast grafts alone, or Schwann cell/fibroblast co-grafts served as controls. At 3 weeks after injury/transplantation, histological analysis revealed that only fibroblast-containing grafts were able to replace the cystic lesion defect. In both co-cultures and co-grafts, Schwann cells and NPC were segregated. Almost all NPC migrated out of the graft into the adjacent host spinal cord. As a consequence, only peripheral-type myelin, but no CNS-type myelin, was detected within co-grafts containing NPC/Schwann cells. Corticospinal axon regeneration into Schwann-cell-containing co-grafts was reduced. Taken together, Schwann cells within NPC grafts contribute to remyelination. However, Schwann cells fail as a supporting platform to maintain NPC within the graft and impair CNS axon regeneration; this makes them an unfavorable candidate to support/augment NPC grafts following spinal cord injury.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Axons / physiology
  • Cell Movement
  • Cell Survival
  • Coculture Techniques
  • Cysts / etiology
  • Cysts / pathology
  • Disease Models, Animal
  • Female
  • Fluorescent Antibody Technique, Indirect
  • Myelin Sheath / metabolism
  • Myelin Sheath / physiology
  • Nerve Regeneration
  • Neurons
  • Rats
  • Rats, Inbred F344
  • Schwann Cells / cytology*
  • Schwann Cells / physiology
  • Schwann Cells / transplantation*
  • Spinal Cord Injuries / complications
  • Spinal Cord Injuries / pathology
  • Spinal Cord Injuries / therapy*
  • Stem Cell Transplantation*
  • Stem Cells / cytology*
  • Stem Cells / physiology