Phenotypic study after cultivated limbal epithelial transplantation for limbal stem cell deficiency

Abstract

Objective: To report phenotypic analysis of epithelia before and following cultivated limbal epithelial transplantation (CLET) for eyes with limbal stem cell deficiency.

Methods: Six patients with limbal stem cell deficiency (3 with alkali burns, 2 with Stevens-Johnson syndrome, and 1 with pseudo-ocular cicatricial pemphigoid) were subjected to CLET and subsequent keratoplasty. Immunohistochemical analysis for cytokeratin 3, cytokeratin 13, MUC5AC (Mucin 5 subtype AC), and alpha smooth muscle actin was performed in specimens obtained at CLET and keratoplasty. Clinical outcome was assessed according to epithelial phenotype, visual acuity, neovascularization, and graft clarity.

Results: Secondary keratoplasty was performed following CLET during a mean interval of 6.8 months. Postoperative visual acuity improved by more than 2 lines over a mean +/- SD observation period of 25.1 +/- 13.2 months following keratoplasty, with reduction of neovascularization. Phenotypic study revealed that epithelia were positive for cytokeratin 13 and MUC5AC, but negative for cytokeratin 3, with alpha smooth muscle actin-positive cells in the stroma in all patients before CLET. After CLET, 4 eyes showed positive immunostaining to cytokeratin 3 but negative immunostaining to cytokeratin 13 and MUC5AC, with no alpha smooth muscle actin-positive cells.

Conclusion: Cultivated limbal epithelial transplantation is a useful approach in the treatment of limbal stem cell deficiency, restoring a feasible microenvironment in the ocular surface and securing a corneal epithelial phenotype.