Phenotypic Characterization of Corneal Epithelium in Long-Term Follow-Up of Patients Post-Autologous Cultivated Oral Mucosal Epithelial Transplantation

Abstract

Purpose:To analyze the phenotype of the corneal epithelium in patients with long-term follow-up who underwent autologous cultivated oral mucosal epithelial transplantation (COMET) using in vivo confocal microscopy (IVCM) and impression cytology with immunofluorescence staining (ICIF).Methods: Thirteen eyes from patients with severe limbal stem cell deficiency, who underwent COMET at least 48 months before, were recruited in this noncomparative cohort study. After eye examination, IVCM and ICIF were performed. Clinical manifestations of the cornea were evaluated and compared with epithelial findings detected by IVCM and ICIF [cytokeratin (CK) 3, CK7, and CK12]. Two corneal buttons derived from patients receiving the corneal transplantation post-COMET were sent for immunohistochemistry (CK3, CK6, CK7, CK12, paired box gene 6, p63, zonula occludens-1, and integrin b -1). Results:The mean age of patients was 51.2 6 20.6 years, and the mean follow-up time since COMET was 78.7 6 16.3 months. Six of 13 eyes showed clinically successful COMET. In these eyes, IVCM demonstrated predominant cornea-like epithelium and ICIF reported positivity for CK3 and CK12, confirming the presence of oral mucosal and corneal epithelium. Meanwhile, 7 eyes showed total conjunctiv-alization, corresponding with substantial conjunctival epithelium detected by IVCM and positivity for conjunctival (CK7) and oral mucosal epithelial (CK3) markers detected by ICIF. The immunohistochemistry of corneal buttons stained positive for oral mucosal, corneal epithelial, and stem cell markers (CK3, CK12, and p63). Conclusions:In long-term follow-up of COMET, epithelium of successful patients demonstrated cornea-like phenotype, whereas failed cases revealed mainly conjunctival phenotype. However, there were evidences that oral mucosal epithelial cells remained across the cornea in both successful and failed COMET as detected by IVCM and ICIF.

Successful Ocular Surface Reconstruction in Complete Ankyloblepharon With the Simple Oral Mucosal Epithelial Transplantation Technique: A Case Report

“…We speculate that the transplanted oral mucosal stem cells transdifferentiate into corneal epithelial cells in response to the signals of corneal niche. 13,14 Of interest, the specific marker for corneal epithelium remains present up to 1 year, consistent with our previous COMET study 14 (Fig. 2F).…”

Lack of Elevated Expression of TGFβ3 Contributes to the Delay of Epithelial Wound Healing in Diabetic Corneas

“…65 Biomaterialfree cultured oral mucosal epithelial cell sheets have been used successfully in ocular reconstruction for subjects with total LSCD. 66,67 Our study revealed that, in the human cornea, similar to mice and rats, wounding induced upregulation of both TGFβ1 and TGFβ3 expression in healing epithelia in normoglycemia corneas, whereas hyperglycemia suppressed the expression of TGFβ3 but not TGFβ1, delaying epithelial wound closure. Importantly, human keratoconus cells expressed less TGFβ3 but not TGFβ1 compared to normal human corneal fibroblasts.…”

The clinical efficacy of a new surgical technique of oral mucosal epithelial transplantation for severe ocular surface disorders

“…Alternative stem cell sources as aforementioned, including oral mucosal epithelial cells (15,16), mesenchymal stem cells (18, 19), hair follicle stem cells (20), and human pluripotent stem cells (21). Among them, cultivated oral mucosal epithelial sheet transplantation (COMET) was used relatively frequently and veri ed to be effective (15)(16)(17)(31)(32)(33). Others were seldom applied in clinical uses and lack of evaluations.…”