NATIONAL EYE INSTITUTEGut bacteria may provide the trigger for autoimmune uveitis, a destructive inflammation of the eye, researchers at the US National Eye Institute (NEI) reported in a study published today (August 18) in Immunity. Autoimmune uveitis is a painful condition that can lead to debilitating blindness. It often hits adults 20 to 60 years old, and is responsible for up to 15 percent of all blindness and severe visual impairment in developed countries.
Researchers believe activated retina-specific T cells attack the eye, causing the inflammation, but the antigen that activates those T cells lies inside the normally immune-privileged eye, meaning T cells are not able to circulate in that area. How those T cells become activated without exposure to the eye has been poorly understood. The NEI’s Reiko Horai, Rachel Caspi, and their colleagues used a mouse model prone to developing uveitis and found that the animals’ intestines showed signs of increased T cell activation prior to the onset of uveitis.
“It’s the first study to show the potential of the microbiome to induce an autoimmune disease specific to the eye,” said Andrew Taylor, an ocular immunologist at the Boston University School of Medicine who was not involved ...
