Outcomes and DNA analysis of ex vivo expanded stem cell allograft for ocular surface reconstruction
Received 9 December 2003; accepted 8 September 2004. published online 07 January 2005.
Purpose
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.
Design
Retrospective noncomparative case series.
Participants
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).
Intervention
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.
Main outcome measures
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.
1Corneo-Plastic Unit, Queen Victoria Hospital, East Grinstead, United Kingdom
2Blond McIndoe Centre, Queen Victoria Hospital, East Grinstead, United Kingdom
3East Grinstead Eye Bank, Queen Victoria Hospital, East Grinstead, United Kingdom
Correspondence to Sheraz M. Daya, MD, FACP, FACS, Director, Corneo-Plastic Unit and Eye Bank, Queen Victoria Hospital, East Grinstead, West Sussex, RH19 3DZ, United Kingdom
Manuscript no. 230850.
Dr Martin's current affiliation is Smith and Nephew, York, United Kingdom.
Funded by the East Grinstead Medical Research Trust, East Grinstead, United Kingdom; the John Ellerman Foundation, London, United Kingdom; the Band Trust, London, United Kingdom; and the Eye Bank Association of America, Washington, DC.
Presented in part at: American Academy of Ophthalmology meeting, November, 2003; Anaheim, California.
ABSTRACT