reprinted from the National Institutes of Health
The inflammatory eye disorder autoimmune uveitis occurs when a person’s immune system goes awry, attacking proteins in the eye. What spurs this response is a mystery, but now a study on mice suggests that bacteria in the gut may provide a kind of training ground for immune cells to attack the eye. The study was conducted by researchers at the National Eye Institute (NEI), part of the National Institutes of Health.
Evidence increasingly suggests that there is an association between the microbiota in the gut — bacteria, fungi and viruses — and the development of autoimmune disorders. Findings from this study suggest how that association may be made and therefore have implications about the origins of autoimmune diseases not only in the eye, but also elsewhere in the body, sai
d Rachel R. Caspi, Ph.D., a senior investigator at NEI whose lab led the study.
Autoimmune uveitis accounts for more than 10 percent of severe visual disability in the United States. Corticosteroids provide a blanket approach to the disorder by quelling inflammation, but their long-term use can lead to adverse side effects.
Understanding what spurs autoimmune uveitis is fundamental to the development of safer long-term therapies and possibly even strategies for preventing it, said Reiko Horai, Ph.D., a staff scientist at NEI and a lead author of the study, published in the journal Immunity. Carlos R. Zarate-Blades, Ph.D., a postdoctoral fellow at NEI, is the other lead author.
The eye is one of the places in the body that has immune privilege meaning it is protected by a blood-tissue barrier that physically separates it from the rest of the body and minimizes the exchange of substances and blood-borne cells going in and out of the eye.