Stem Cells May Help Improve Vision
29 May, 2007 07:29 pm
University of Cincinnati (UC) researchers have recently found evidence that adult bone marrow stem cells may help cure certain genetic eye diseases.
The UC team, including myself and Dr. Hongshan Liu, research scientist in the department of ophthalmology, have completed a study in mice that showed bone marrow stem cells can switch roles and “differentiate” into cells that produce keratocan, a natural protein involved in the growth of the cornea—the transparent, outer layer of the eyeball.
As a result, we feel that if we can place stem cells inside the cornea, they will repair the lost function of the mutated gene that is causing the problem. Then, the stem cells can renew themselves and maintain effective treatment longer, if not forever.
We knew from existing research that adult bone marrow stem cells, which are “multipotent,” were capable of differentiating to various other cell types, such as those in the heart, liver and gastrointestinal tract. However, we wanted to see if stem cells could differentiate to repair eye mutations.
In the laboratory, we induced corneal abnormalities that mimicked genetic eye mutations and then injected bone marrow stem cells into the corneas of mouse models to see if the mutations were altered in any way. Mice were used because their eye structure is similar to that of humans.
The study showed that after only one week, the bone marrow stem cells injected into the corneas of the mouse models began to change shape from a round to a branchlike appearance, and produced keratocan. The number of stem cells taking on the role of keratocan increased as the weeks passed.
We concluded that bone marrow stem cells can contribute to the formation of connective tissues, and if we can change the function of non-corneal bone marrow stem cells by introducing them into human corneas, we can possibly repair the loss of visual sharpness caused by mutations.
We are now planning a clinical trial overseas. If the trial succeeds and our findings are correct, the procedure could help prevent blindness in future generations who suffer from genetic corneal diseases.
Our findings were presented at the annual meeting of the Association for Research in Vision and Ophthalmology held in Ft. Lauderdale, Fla., May 9 and 10. The study was funded by grants from the National Eye Institute, Research to Prevent Blindness and Ohio Lions Eye Research Foundation.