Stem Cell Research in Ophthalmology: Good Model of Regenerative Medicine

Geeta K Vemuganti, MD, DNB, FNAMS

Head, Ophthalmic Pathology Service & Sudhakar and Sreekant Ravi Stem Cell Laboratory, Prof. Brien Holden Research Centre Hyderabad Eye Research Foundation, L V Prasad Eye Institute, Hyderabad

Abstract

Limbal stem cell deficiency has been a challenging clinical problem, the current treatment of which involves replenishing the depleted limbal stem cell pool by either limbal tissue transplantation or use of cultivated limbal epithelial sheets. We established a simple, feeder-cell free, cost-effective way of culturing the corneal epithelium from limbal tissues within 2 weeks, using human amniotic membrane as a vehicle. The limbal explants derived epithelium showed the presence of differentiated corneal cells as well as stem cells. Our experience with more than 600 cases revealed 65% success at the end of three years, evident in the form of symptomatic relief, intact ocular surface, absence of recurrence and varying degree of visual recovery.

In addition, the corneal buttons from patients who subsequently underwent corneal transplantation for visual rehabilitation provided the unique opportunity of documenting the histologic proof of in-vivo survival, stratification, and restoration of corneal phenotype. Patients with severe ocular surface disease involving surrounding conjunctiva and lid deformities were treated with a novel technique, i.e. a “Composite Culture of Central limbal and Peripheral Conjunctival Epithelium” cultivated on a single amniotic membrane.

To obviate the need for allogenic transplantation and immunosuppression in patients with severe bilateral disease, we evaluated the use of Cultivated Oral Mucosal epithelium Transplation which gives about 30% success. Thus ocular surface reconstruction through cultivated epithelial transplantation fulfills most of the pre-requisites for cell therapy and therefore considered as a successful model in the emerging field of regenerative medicine.