Though glaucoma is a relatively common condition across the developed world, medical researchers have still yet to conclusively identify its primary causes. Believe it or not, one potential culprit could be the body’s very own immune system.
Trouble with a Capital T
This notion comes from a collaborative report between the Massachusetts Institute of Technology (MIT) and Massachusetts Eye and Ear (MEE) hospital. Using mice as test subjects, the study authors directed their focus towards the rodents’ retinas, looking for the presence of T cells. These cells play an essential role in the body’s immune system, as they are tasked with countering hostile invaders.
Under normal circumstances, the retinas are shielded from T cells by a barrier known as the blood-retina barrier, a densely-packed layer of cells. While T cells are certainly useful in the bloodstream, their presence in the retinas could
easily cause highly-damaging inflammation. The MIT/MEE team hypothesized that the elevated eye pressure associated with glaucoma could result from a T cell breach of the the blood-retina barrier. To put their theory to the test, the researchers examined the eyes of their four-legged subjects. Sure enough, T cells had somehow managed to
make their way into the mice’s retinas.
From Mice to Humans
Having found immune cells in the eyes of mice, the study authors then subsequently examined the eyes of humans struggling with glaucoma. They found that the eyes of these volunteers had five times the number of certain T cells than normal. Specifically, the T cells observed in these subjects targeted heat shock proteins within the retina, which could hinder the body’s ability to respond to stress or damage in this area.
If their discovery is indeed correct, the authors contend that glaucoma could be addressed by restraining an overactive immune system. For their part, the MIT/MEE team doesn’t plan to rest on their laurels; in addition to studying if other parts of the immune system contribute to glaucoma, their future work will examine possible connections between T cell activity to neurodegenerative disorders.
