title: Outcomes and DNA analysis of ex vivo expanded stem cell allograft for ocular surface reconstruction.
abstract: OBJECTIVE
  To investigate the outcome of a new technique of ex vivo expanded stem cell allograft for limbal stem cell deficiency (LSCD), and to characterize the ocular surface genotype after surgery.
  
  
  METHODS
  Retrospective noncomparative case series.
  
  
  METHODS
  Ten eyes of 10 patients with profound LSCD arising from ectodermal dysplasia (3 eyes), Stevens-Johnson syndrome (3 eyes), chemical injury (2 eyes), thermal injury (1 eye), and rosacea blepharoconjunctivitis (1 eye).
  
  
  METHODS
  Allogeneic corneal limbal stem cells were cultured on plastic and transplanted to the recipient eye after removal of conjunctival pannus. Amniotic membrane was applied in a bandage capacity. The procedure was combined with other reconstructive surgery in 2 cases. Nine patients received systemic cyclosporin A immunosuppression, and the DNA genotype was investigated with surface impression cytology.
  
  
  METHODS
  Parameters of LSCD, including vascularization, conjunctivalization, inflammation, epithelial defect, photophobia, and pain.
  
  
  RESULTS
  The mean follow-up period was 28 months (range, 12-50). Seven of 10 eyes (70%) had improved parameters of LSCD at final follow-up and were considered successes. Four (40%) had improved visual acuity, including 3 having had further procedures for visual rehabilitation. Three patients failed to improve-1 with a thermal burn and lid deformity, 1 with Stevens-Johnson syndrome and severe dry eye, and 1 with ectodermal dysplasia who developed an epithelial defect at 26 months. DNA analysis of the first 7 cases showed no ex vivo donor stem cell DNA present beyond 9 months.
  
  
  CONCLUSIONS
  Ex vivo expanded stem cell allograft is a useful technique for restoring the ocular surface in profound LSCD. The absence of donor DNA beyond 9 months suggests that ongoing immunosuppression may be unnecessary and raises questions regarding the origin of the host corneal epithelium.
authors.affiliation: Corneo-Plastic Unit, Queen Victoria Hospital, East Grinstead, West Sussex, United Kingdom. sdaya@centreforsight.com
authors.forename: Sheraz M
authors.initials: SM
authors.lastname: Daya
authors.forename: Adam
authors.initials: A
authors.lastname: Watson
authors.forename: Justin R
authors.initials: JR
authors.lastname: Sharpe
authors.forename: Osama
authors.initials: O
authors.lastname: Giledi
authors.forename: Andrea
authors.initials: A
authors.lastname: Rowe
authors.forename: Robin
authors.initials: R
authors.lastname: Martin
authors.forename: S Elizabeth
authors.initials: SE
authors.lastname: James
mesh_terms: D000293:Adolescent; D000328:Adult; D000650:Amnion / Q000637:transplantation; D002478:Cells, Cultured; D002675:Child, Preschool; D003316:Corneal Diseases / Q000473:pathology / Q000601:surgery*; D004247:DNA / Q000032:analysis*; D019573:Epithelium, Corneal / Q000637:transplantation*; D005260:Female; D005838:Genotype; D006801:Humans; D007165:Immunosuppression Therapy; D016850:Limbus Corneae / Q000166:cytology*; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D012189:Retrospective Studies; D033581:Stem Cell Transplantation; D013234:Stem Cells / Q000737:chemistry*; D014184:Transplantation, Homologous
chemical_list: D004247:DNA