Limbal stem cell and oral mucosal epithelial transplantation from ex vivo cultivation in LSCD-induced rabbits: histology and immunologic study of the transplant epithelial sheet

Abstract

© 2016, Springer Science+Business Media Dordrecht. Purpose: To evaluate the results of cultivated limbal epithelial and oral mucosal epithelial transplantation (CLET and COMET) in limbal stem cell deficiency (LSCD)-induced rabbit model. Materials and methods: Six New Zealand white rabbits were divided into two groups of three rabbits each. Limbal tissue was harvested from the first group, and oral mucosal biopsy was obtained from the second group. The tissues were cultured using an explant technique with amniotic membrane as a substrate and co-culture with the 3T3 fibroblast and air-lifting method. The right eye of each rabbit was induced to have LSCD using alkali burns. After three weeks, the LSCD-induced rabbit eyes were transplanted with the cultivated limbal and oral mucosal epithelial sheet in the first and second group, respectively. The transplanted eye was evaluated weekly post-operation. After 2 months, all transplanted eyes were enucleated and the epithelial morphology and phenotype of ocular surfaces were studied and compared with normal corneal and oral mucosal tissue. Results: At 2-month post-transplantation, the eyes of four animals recovered with corneal transparency, one partially recovered, and one failed. The histology of the majority of transplanted eyes was stratified layers of corneal epithelia similar to normal rabbit cornea with some different findings such as goblet cells in the limbal region. Corneal epithelial thickening and stromal vascularization in two animals were observed. Phenotypic characterization of transplanted eyes showed a similar pattern of marker expression with the absence of p63 expression in the limbal or corneal epithelium in the COMET group. Conclusions: The histology and phenotype of transplanted eyes after CLET and COMET were most likely to have similar characteristics as a normal healthy rabbit eye even though the COMET eyes have some inferior characteristics to the CLET eyes.