Corneal injuries can be treated by growing stem cells from a tiny biopsy of the patient's undamaged eye and then placing them on the injury site, according to a new study conducted by researchers at the University of Pittsburgh's School of Medicine. Damage to the cornea leads to cloudiness or haziness and makes it hard or impossible to see. The body usually responds to corneal injuries by making scar tissue. Scientists found that delivery of stem cells initiates regeneration of healthy corneal tissue rather than scar tissue leaving a clear, smooth surface.
Study lead author Sayan Basu, MBBS, MS, a corneal surgeon at the L.V. Prasad Eye Institute in Hyderabad, India, joined Dr. James L. Funderburgh's laboratory in Pittsburgh. Dr. Basu had previously developed a technique to obtain ocular stem cells from tiny biopsies at the surface of the eye and the limbus, a region between the cornea and sclera. Removal of tissue from this region heals faster with little discomfort and no disruption in vision. After collecting biopsies from banked human donor eyes, the research team multiplied the cells in a culture plate using human serum to nourish them. These human stem cells were then tested in a mouse model of corneal injury. Corneal stem cells were glued to the injury site with the help of gel of fibrin, a protein found in blood clot that is commonly used as a surgical adhesive. It was seen that with four weeks of treatment the scarred corneas of mice healed and became clear again, while those of untreated mice remained clouded.
Using the patient's own cells from the uninjured eye for this process could bypass rejection concerns. This process could be very helpful, particularly in places that do not have corneal tissue banks for transplant. The findings could one day rescue vision for millions of people worldwide and decrease the need for corneal transplants.
The findings are published in Science Translational Medicine.