Alpha-enolase immunohistochemical study of stem cels in limbal autograft tissue

Abstract

The purpose was to detect the presence of stem cells in the limbus and cornea following limbal autotransplantation for chemical eye injury. Fifteen New Zealand white rabbits were used in the study. The first group (n=5) served as healthy controls, in group 2 (n=5) one eye of each rabbit was burnt by 1 N NaOH and in the last group (n=5), the same chemical injury was followed by limbal autotransplantation from the contralateral eye. The eyes were examined clinically and studied by immunohistochemistry after the enucleation. A monoclonal antibody against alpha-enolase - a biochemical marker for stem cells, was used for immunohistochemistry. The density of cells in both limbus and the cornea was calculated per mm2. The Tukey-Kramer parametric test was used for statistical evaluation. Healthy limbus and basal corneal layers showed numerous a-enolase positive cells. The injured group showed marked depletion of these cells (p<0.0001). Compared to this group the treated group, exibited a statistically significant (p<0.0001) increase in a-enolase positive cells. This study provides evidence that limbal autograft transplantation transfers stem cells to the chemically injured area with depletion of these cells. To demonstrate this we used a monoclonal antibody against alpha-enolase for immunohistochemical analysis of the presence of stem cells in transplant tissue and its surrounding milieu. We showed that the transplanted limbal graft was the source of corneal epithelial stem cells.