title: Anterior cruciate ligament regeneration using mesenchymal stem cells and collagen type I scaffold in a rabbit model.
abstract: OBJECTIVE
  The objective of this study was to determine whether using mesenchymal stem cells (MSC) seeded in a collagen type I scaffold would be sufficient to regenerate the torn anterior cruciate ligament (ACL).
  
  
  METHODS
  Anterior cruciate ligament transection was performed on both knees in 10 New Zealand rabbits and then repaired with as follows: suture alone (suture-treated group, n = 6), suture associated with collagen type I scaffold (collagen type I scaffold-treated group, n = 8) or suture associated with autologous MSC seeded on collagen type I scaffold (MSC/collagen type I scaffold-treated group, n = 6). At 12-week post-intervention, the animals were killed and the ACLs were characterised macroscopically and histologically. Data of the 3 groups were against normal ACL (normal group, n = 10).
  
  
  RESULTS
  Macroscopic observation found that in MSC/collagen type I scaffold group, 33% of specimens showed a complete ACL regeneration, with a tissue similar to the normal ACL. Regeneration was not observed in the group treated with suture alone or associated with collagen type I scaffold without cells. In the latter, only a reparative attempt at the ends was observed. Histological analysis of the regenerated ACL showed a tissue with organised collagen and peripheric vessels.
  
  
  CONCLUSIONS
  These results provide evidence that the use of MSC seeded in a collagen type I scaffold in the treatment of ACL injuries is associated with an enhancement of ligament regeneration. This MSC-based technique is a potentially attractive tool for improving the treatment of ACL ruptures.
authors.affiliation: Orthopedic Surgery Department, Clínica Alemana de Santiago, Avda Vitacura 5951, Santiago, Chile, dhfigueroa@gmail.com.
authors.forename: David
authors.initials: D
authors.lastname: Figueroa
authors.forename: Maximiliano
authors.initials: M
authors.lastname: Espinosa
authors.forename: Rafael
authors.initials: R
authors.lastname: Calvo
authors.forename: Maximiliano
authors.initials: M
authors.lastname: Scheu
authors.forename: Alex
authors.initials: A
authors.lastname: Vaisman
authors.forename: Marcela
authors.initials: M
authors.lastname: Gallegos
authors.forename: Paulette
authors.initials: P
authors.lastname: Conget
mesh_terms: D000818:Animals; D016118:Anterior Cruciate Ligament / Q000503:physiopathology* / Q000601:surgery; D000070598:Anterior Cruciate Ligament Injuries; D001672:Biocompatible Materials; D024042:Collagen Type I; D004195:Disease Models, Animal; D007718:Knee Injuries / Q000503:physiopathology* / Q000601:surgery; D045164:Mesenchymal Stem Cell Transplantation; D059630:Mesenchymal Stem Cells; D011817:Rabbits; D012038:Regeneration; D054457:Tissue Scaffolds
chemical_list: D001672:Biocompatible Materials; D024042:Collagen Type I