Genetic analysis of allogenic donor cells after successful allo-limbal epithelial transplantation in simple and cultivated limbal epithelial transplantation procedures.

This non-comparative cohort study investigated long-term donor cell survival after allogenic simple/cultivated limbal epithelial transplantations (allo-SLET/allo-CLET, respectively) by genetic analysis. Transplanted corneal epithelial cells, which underwent impression cytology and/or corneal-button biopsy, were examined for personal identities of autosomal short-tandem repeats; the percentages of donor cells were calculated based on matching recipient or donor buccal-DNA references. Twelve patients were included; 4 underwent allo-CLET, 8 underwent allo-SLET. Eight patients (67%) had total limbal stem cell deficiency (LSCD). Genetic analysis was performed postoperatively (mean, 55.3 months). Donor cells were detected in 4 of 12 patients (25%), all of whom underwent allo-SLET; 1 patient had a donor genotype and 3 patients had a mixed donor/recipient genotype. The longest time of donor cell detection was 30 months. Seven patients (58%) used systemic immunosuppressives at the time of genetic analysis (mean use, 22.5 months). Allogenic donor cells survived in both procedures for the long term postoperatively, which encourages the long-term use of systemic immunosuppressives. Donor cells may not be the only factor in graft survival, in that most successful cases had a recipient profile. Their presence for a specific time may promote niches for the patients' own cells to repopulate, especially for partial LSCD.

Epithelial analysis of simple limbal epithelial transplantation in limbal stem cell deficiency by in vivo confocal microscopy and impression cytology.

Simple limbal epithelial transplantation (SLET) is a relatively new treatment for severe limbal stem cell deficiency. Outcomes of treatment are typically determined based on clinical manifestations. In this prospective-multicenter study, we aimed to analyze the epithelial phenotypes of the corneas after SLET using IVCM and IC, and correlated them with clinical findings. Ten eyes of nine patients, who underwent SLET (five autologous SLET and five living-related SLET) were recruited. A set of examinations included slit-lamp biomicroscopy, corneal in vivo confocal microscopy (IVCM), and impression cytology (IC) was performed in all eyes at least twice (≥ 3-month interval) postoperatively. Then, a correlation between findings of the three examinations was analyzed. There were seven eyes with clinical success (no central neovascularization) showed pure corneal epithelial phenotype or mixed corneal-conjunctival phenotypes (mostly cornea) in either IVCM or IC. Three eyes with clinical failure, presented with peripheral and central neovascularization, showed total or predominant conjunctival phenotype in IVCM and sole conjunctival phenotype in IC. From a total of 22 sets of examinations, there was a high correlation between clinical manifestation vs. IC (κ = 0.844, observed agreement = 81.82%) and a substantial correlation between clinical manifestation vs. IVCM (κ = 0.727, observed agreement = 76.19%) and between IVCM versus IC (κ = 0.729, observed agreement = 76.19%). In conclusion, IVCM and IC facilitate determination of epithelial phenotype of the cornea after SLET. There was a substantial to high correlation between IVCM, IC and clinical presentations. Findings observed by IVCM and IC may allow early detection of epithelial alterations in eyes underwent SLET before clinical recognition.