title: Combined treatment with platelet-rich plasma and brain-derived neurotrophic factor-overexpressing bone marrow stromal cells supports axonal remyelination in a rat spinal cord hemi-section model.
abstract: OBJECTIVE
  Combining biologic matrices is becoming a better choice to advance stem cell-based therapies. Platelet-rich plasma (PRP) is a biologic product of concentrated platelets and has been used to promote regeneration of peripheral nerves after injury. We examined whether PRP could induce rat bone marrow stromal cells (BMSCs) differentiation in vitro and whether a combination of BMSCs, PRP and brain-derived neurotrophic factor (BDNF) could provide additive therapeutic benefits in vivo after spinal cord injury (SCI).
  
  
  METHODS
  BMSCs and BDNF-secreting BMSCs (BDNF-BMSCs) were cultured with PRP for 7 days and 21 days, respectively, and neurofilament (NF)-200, glial fibrillary acidic protein (GFAP), microtubule-associated protein 2 (MAP2) and ribosomal protein S6 kinase (p70S6K) gene levels were assessed. After T10 hemi-section in 102 rats, 15-μL scaffolds (PRP alone, BMSCs, PRP/BMSCs, BDNF-BMSCs or PRP/BDNF-BMSCs) were transplanted into the lesion area, and real-time polymerase chain reaction, Western blot, immunohistochemistry and ultrastructural studies were performed.
  
  
  RESULTS
  The messenger RNA expression of NF-200, GFAP, MAP2 and p70S6K was promoted in BMSCs and BDNF-BMSCs after culture with PRP in vitro. BDNF levels were significantly higher in the injured spinal cord after implantation of BDNF-BMSCs. In the PRP/BDNF-BMSCs group at 8 weeks postoperatively, more GFAP was observed, with less accumulation of astrocytes at the graft-host interface. Rats that received PRP and BDNF-BMSC implants showed enhanced hind limb locomotor performance at 8 weeks postoperatively compared with control animals, with more axonal remyelination.
  
  
  CONCLUSIONS
  A combined treatment comprising PRP and BDNF-overexpressing BMSCs produced beneficial effects in rats with regard to functional recovery after SCI through enhancing migration of astrocytes into the transplants and axonal remyelination.
authors.affiliation: The Second Affiliated Hospital (Binjiang Branch) Zhejiang University School of Medicine, Hangzhou Binjiang Hospital, Hangzhou, China.
authors.forename: Tengfei
authors.initials: T
authors.lastname: Zhao
authors.forename: Weiqi
authors.initials: W
authors.lastname: Yan
authors.forename: Kan
authors.initials: K
authors.lastname: Xu
authors.forename: Yiying
authors.initials: Y
authors.lastname: Qi
authors.forename: Xuesong
authors.initials: X
authors.lastname: Dai
authors.forename: Zhongli
authors.initials: Z
authors.lastname: Shi
mesh_terms: D000818:Animals; D001369:Axons / Q000378:metabolism / Q000637:transplantation*; D016026:Bone Marrow Transplantation; D019208:Brain-Derived Neurotrophic Factor / Q000008:administration & dosage*; D002454:Cell Differentiation; D002478:Cells, Cultured; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D006801:Humans; D008297:Male; D059630:Mesenchymal Stem Cells; D009416:Nerve Regeneration; D053657:Platelet-Rich Plasma / Q000737:chemistry; D051381:Rats; D020127:Recovery of Function; D013119:Spinal Cord Injuries / Q000473:pathology / Q000503:physiopathology / Q000628:therapy*
chemical_list: D019208:Brain-Derived Neurotrophic Factor; D005904:Glial Fibrillary Acidic Protein