Imagine waking to a bright, sunny day, but not really being able to see. Some people go their whole lives without witnessing that vivid red ball from their youth or the facial features of a loved one. Kristina Narfström, a veterinary ophthalmologist at the University of Missouri, is doing research that promises to provide some light at the end of the tunnel.
Narfström is interested in the hereditary blindness that originates in human photoreceptor cells. She studies dogs and cats that contract blinding conditions similar to those found in human beings.
Genetic transfer can be used to replace dead photoreceptor cells. Narfström employs this method to correct protein defects in the eyes. The procedure involves injecting a construct – a vehicle that brings the protein the correct DNA – into the retina cell. The construct is then transported into the nucleus, where it is translated to make the correct protein.
Narfström discusses various treatment measures for blindness. The prevention of photoreceptor death, she says, can be treated with different proteins and vitamins, or new cells may be inserted in the retina to replace the dying cells.
Another treatment involves inserting a small microchip to replace the dead photoreceptors and get the electrical juices of the eye flowing. This device, known as an Artificial Silicon Retina (ASR), is conceptually similar to a bionic eye. The ASR was designed more than 15 years ago to enhance human vision. Narfström hopes that her research will improve the chip.