Nearly 10% of all Americans suffer from Dry eye syndrome (DES), which makes this disorder one of the most common ocular diseases. Most of the currently-available treatments are palliative, but few therapeutic agents target the biological causes of DES. Many factors contribute to DES, but one of the most important factors in the cause of DES is inflammation of the ocular surface.
Since mesenchymal stem cells (MSCs) have been shown to suppress inflammation, using MSCs to treat DES seems to be a viable treatment option. MSCs can also repair tissues by regulating excessive immune responses in various diseases.
Thus Joo Youn Oh from the Seoul National University in Seoul, Korea and his colleagues investigated the therapeutic potential of MSCs in a mouse model of an inflammation-mediated dry eye. They induced DES in these mice by injecting a plant protein into the eye that grabs sugars into the eye. This protein injection dries out the eyes in these mice and induces a kind of DES-like condition.
Then they found that the administration of MSCs into the eye reduced the infiltration of immune cells into the eye and overall decreased eye inflammation. Administration of MSCs into the eye also significantly increased tear production and also increased the number of conjunctival goblet cells, which secrete lubricating mucus so that the eye lid slides gently over the eye surface. Further investigation showed that the structural integrity of the eye surface, known as the cornea, was well-preserved by MSCs.
When taken together, ocular administration of MSCs seem to suppress the inflammation that either accompanies or contributes to DES. These results also suggest that MSCs may provide a potential therapy for those diseases that cause inflammation of the ocular surface and adversely affect the eye because of it.