title: Cell migration after synovium graft interposition at tendon repair site.
abstract: BACKGROUND
  We have recently reported that interpositional synovium grafts from tendon sheath have a potential to accelerate tendon healing when implanted at the repair site. The purpose of this study was to investigate the effect of orientation of the synovium after synovium graft transplantation, by comparing the ability of cells from the visceral and parietal surfaces to migrate into the tendon in a canine tissue culture model.
  
  
  METHODS
  The synovium graft was placed within a complete tendon laceration, with either the visceral or parietal surface facing the proximal end of the lacerated tendon. The number of migrating cells was quantified by a cell migration assay. Qualitative immunohistochemistry and confocal laser microscopy were also used at day 10.
  
  
  RESULTS
  Many labeled synovial cells were observed within the tendon to which the visceral surface of the synovium graft was facing. Migrated cells were also observed on the parietal side, but there were fewer cells compared to visceral surface cells. Migrating cells all expressed α-smooth muscle actin.
  
  
  CONCLUSIONS
  We found that graft orientation affected cell migration. Whether this finding has clinical significance awaits in vivo study.
authors.affiliation: Biomechanics Laboratory, Division of Orthopedic Research, Mayo Clinic, 200 1st Street S.W., Rochester, MN 55905 USA.
authors.forename: Masanori
authors.initials: M
authors.lastname: Hayashi
authors.forename: Chunfeng
authors.initials: C
authors.lastname: Zhao
authors.forename: Kai-Nan
authors.initials: KN
authors.lastname: An
authors.forename: Peter C
authors.initials: PC
authors.lastname: Amadio
keywords: Cell migration; Synovial cells; Synovium graft; Tendon healing