Inflammation is a normal part of the body's defense mechanism against injury or infection. Part of the inflammatory response is the activation of microglia, which are cells whose jobs include engulfing and "eating" your body's own damaged cells. In progressive retinal degeneration caused by retinitis pigmentosa, microglia in the retina sometimes become overactive and start to "eat" photoreceptors that are not yet damaged. These overactive microglia can cause retinal degeneration and vision loss to progress even faster. For this reason, anti-inflammatory treatments that reduce microglia activity could help to slow down vision loss in retinal degeneration.
In this study, researchers focused on delivering anti-inflammatory drugs to mice with retinal degeneration (caused by a mutation in Pde6b) as a way to protect photoreceptors from being attacked by microglia. Specifically, they used a drug that inhibits a protein involved with inflammation called EZH2. They incorporated this drug into a hydrogel compound to make sure it would only be active once it got to the target location.
What this means for Usher syndrome: Increased inflammation in the retina can happen any time there is retinal degeneration, including in all subtypes of Usher syndrome. Although this anti-inflammatory hydrogel treatment would not prevent vision loss in Usher syndrome, it could slow down the rate of progression.
