Abstract
Purpose: :
Cultivated oral mucosal epithelial transplantation (COMET) is a representative procedure for ocular surface reconstruction. Its favorable clinical efficacy has been reported. We experienced 2 post-COMET cases with severe exacerbation of ocular surface inflammation after secondary optical keratoplasty. In this study, we examined the histology of ocular surface tissue to elucidate the pathogenesis of this inflammation.
Methods: :
Subjects were two men with chemical injury (29 and 33 years old) who underwent penetrating keratoplasty for optical improvement after obtaining a clinically stable ocular surface by COMET. Severe ocular surface inflammation occurred immediately after keratoplasty, resulting in primary graft failure. We compared immunohistochemically the excised stable ocular surface tissue with the inflamed tissue (CD3, CD4, CD8, CD11c, CD19, and CD45).
Results: :
Pronounced stratification of oral mucosal epithelium was observed and was especially in the inflamed tissue. CD3, CD4-positive cells were localized within the substantia propria in the stable tissue. However, in the inflamed tissue, CD3, CD4-positive cells had permeated into the epithelial layer. CD11c-positive cells were observed throughout the epithelial layers in the inflamed tissue, but CD11c-positive cells were also observed in the basal layer even in the stable tissue. Morphology of CD11c-positive cells was dendritic in both tissues. Neither CD8 nor CD19-positive cells were detected in either tissue.
Conclusions: :
In our cases, even clinically stable ocular surface tissue, immunocompetent cells were present in the epithelial layer. Further immunohistological analysis of cases is necessary to evaluate the association between these inflammatory cells and the severe exacerbation of inflammation.
Keywords: inflammation • immunohistochemistry • transplantation