Abstract
Purpose :
To describe and analyze allogeneic limbal stem cell transplantation expanded in vitro on de-epithelized cryopreserved human amniotic membrane (d-HAM) for corneal surface reconstruction in patients with limbal stem cell deficiency
Methods :
Patients with bilateral limbal stem cell deficiency of any etiology were invited to participate in this interventional study. Allogeneic tissues were constructed with expanded cells derived from cadaveric corneo-scleral rims using de-epithelized human amniotic membrane as a scaffold during 3 weeks. Presence and expression of corneal specific stem cell markers such as ABCB5 and deltaNp63-alpha were studied by means of immunofluorescence and RT-PCR on the expanded cells. Patients underwent pannus dissection from the corneal surface and allogeneic constructed tissues were transplanted. All patients received immunosuppression. The primary outcome was an objective clinical evaluation for the degree of corneal transparency and superficial vascularization.
Results :
All the constructed tissues stratified at least in three layers and expressed mRNA for both deltaNp63-alpha and ABCB5 in equal amounts. The presence of ABCB5+ cells were confined to the cell membrane and the staining was stronger in the basal cells in comparison to those in the more superficial cells. The staining pattern for deltaNp63-alpha was identified into the nucleus. Both markers were positive in all the cells. Four eyes of four patients were included, with a mean age of 56 years. The limbal stem cell deficiency was attributed to diverse etiologies. At seven months of follow-up, no improvement in corneal transparency and superficial vascularization was evident in the four patients, with recurrence of the limbal stem cell deficiency in all of them. The corneal cells morphology remained with the presence of both epithelial and conjunctival cells, and no changes in the modified National Eye Institute Visual Function Questionnaire-25 and visual acuity were evident.
Conclusions :
Allogeneic cultivated limbal stem cell transplantation must be used on other non-immunologic etiologies of limbal stem cell deficiency, as no benefit was shown in this initial report of the first cases, with no improvement in the ocular surface, no change in corneal cell morphology and vision. ABCB5 must be correlated with p63 to determine prognosis in this patients.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.