Dr. William Spencer from Duke University's Albert Eye Institute, awarded $70,000 Knights Templar Eye Foundation Grant For Photoreceptor Research

Dr. William Spencer from the Albert Eye Institute, Duke University Medical Center was awarded a grant for $70,000 for his research entitled: Understanding the roles of ectosomes and the associated microglial response in photoreceptor degeneration.

Like the pixels of a digital camera, the human retina contains millions of photoreceptor cells that individually respond to light and are essential for vision. To function, these cells rely on their light detecting antennas which contain a stack of several hundred light-sensitive disc-shaped membrane structures called “discs”.

Because discs are heavily stressed by light, the photoreceptor cell continuously renews them throughout the entire human lifetime. Unfortunately, genetically inherited mutations in the process of disc renewal cause blinding retinal diseases in pediatric patients. One such disease-linked protein is called PRCD whose mutations lead to a defect in disc formation marked by the shedding of disc fragments outside of the photoreceptor’s antenna structure. These fragments accumulate in a form of vesicles, like garbage, and recruit immune cells that migrate through the retinal tissue and attempt to clear them.

The goal of this study is to determine to what extent this extracellular vesicular material is toxic to the retina and whether the immune cells ameliorate pathology by clearing this material, or their invasion into the space occupied by photoreceptors causes collateral damage and exacerbates disease. The significance of this scientific direction is highlighted by the fact that numerous blindness-causing mutations, in addition to those in PRCD, that affect children are associated with accumulation of extracellular vesicles in the retina. Therefore, addressing the cellular and molecular mechanisms underlying their formation and clearance are key steps in developing future therapeutic strategies.