Culture and characterization of human dental pulp-derived stem cells as limbal stem cells for corneal damage repair

Limbal stem cell deficiency (LSCD) is one of the leading causes of corneal damage. Injury or inflammation in the cornea causes LSCD, which may be unilateral or bilateral depending upon the cause. Limbal epithelial cell implants successfully improve vision in patients with chemical injury-induced LSCD. Transplantation of cultured epithelial stem cells has become a treatment of choice for numerous patients with LSCD. Bilateral LSCD is frequently observed in the general population, where no residual stem cells are available for ex vivo culture. Allografts are associated with a high risk of rejection, neoplasia, and disease transmission. In this respect, allogenic cell populations from other regions in the patient may substitute for allogenic material. In the present study, dental pulp stem cells were cultured in limbal stem cell media and these cells were characterized against limbal stem cells, revealing the significance of using dental pulp stem cell treatment in bilateral LSCD. The morphology and culture pattern of both limbal and dental pulp stem cells grown in limbal stem-specific media were similar. Polymerase chain reaction analysis revealed that stem cell markers were highly expressed in limbal stem cells compared to in dental pulp stem cells, regardless of the medium and scaffold in which they were grown. Although dental pulp stem cell molecular expression is quite low at the transcript level, the functional protein level according to immunocytochemistry and western blot analyses demonstrated that stem cells and corneal differentiation molecule levels were quite high, indicating their potential as limbal stem cells in the respective microenvironment.