- Researchers at Augusta University have discovered a potential treatment path for patients with optic nerve trauma. The team used a mouse model to show that removing the inflammatory enzyme arginase 2, which increases with injury, decreases neuron death in the retina, as well as the degeneration of nerve fibers that connect neurons in the brain. In fact, brain-derived neurotropic factor increased upon removing A2, suggesting that the axons were attempting to repair themselves and, ultimately, to reconnect with the brain. The team are now pursuing several new lines of investigation into the role of A2 in optic nerve injuries, for which there is currently no targeted therapy (1).
- Good news for glaucoma researchers – biologists have found a way to better mimic the environment in the human retina: more-mature models of retinal ganglion cells. Biologists at Indianapolis University-Purdue University discovered that by introducing hPSC-RGCs to astrocytes, they can create cells that are more analogous to human RGCs – the cells primarily damaged by glaucoma. “What we found is that the astrocytes speed up the differentiation and provide a retinal ganglion cell that functions more appropriately and acts more like how we would expect these cells to function in the human retina,” said Jason Meyer, Associate Professor of Biology at IUPUI. “Glaucoma doesn’t develop in immature cells that are still growing; we want to get the cells we study as close as possible to the stage when they start to develop problems (2).”
- Another breakthrough in the glaucoma space: researchers have identified a gene responsible for the onset of pigmentary glaucoma (PG) using a series of tests. They pinpointed a mutation in the PMEL gene as responsible for the sight-threatening condition, which affects 150,000 people in North America alone. By introducing the mutation into zebrafish DNA, they noted altered pigmentation and eye defects very reminiscent to that of a human glaucoma patient. The team also identified unexpected similarities to other neurodegenerative diseases, such as Alzheimer’s. The team hope the findings will raise awareness of potential treatment avenues, with some of the methods used to treat Alzheimer’s potentially being applied to glaucoma (3).
- In a world first, doctors have transplanted tissue created by donor stem cells into patients with limbal stem cell deficiency (LSCD). The randomized clinical trial, led by doctors at the University of Edinburgh and Scottish National Blood Transfusion Service, found that patients who had received the stem cells showed significant repair to their ocular surface over 18 months, which was not seen in those in the control group. Study leader Baljean Dhillon stated in a press release (4), “Our next steps are to better understand how stem cells could promote tissue repair for diseases that are extremely hard to treat and if, and how, they could help to restore vision.”
- X Zhimin et al., “Retinal Neuroprotection From Optic Nerve Trauma by Deletion of Arginase 2”, Front Neurosci., 12, 970 (2018). PMID: 30618589.
- K VanderWall et al., “Astrocytes Regulate the Development and Maturation of Retinal Ganglion Cells Derived from Human Pluripotent Stem Cells”, Stem Cell Reports, 28, S2213-6711 (2018). PMID: 30639213.
- A Lahola-Chomiak et al., “Non-Synonymous variants in Premelanosome Protein (PMEL) cause ocular pigment dispersion and pigmentary glaucoma”, Hum Mol Genet (2018) [Epub ahead of print]. PMID: 30561643.
- J Campbell et al., “Allogeneic Ex Vivo Expanded Corneal Epithelial Stem Cell Transplantation: A Randomized Controlled Clinical Trial”, Stem Cells Transl Med (2019) [Epub ahead of print]. PMID: 30688407.
I’ve always loved telling stories. So much so, I decided to make a job of it. I finished a Masters in Magazine Journalism and spent three years working as a creative copywriter before itchy feet sent me (back)packing. It took seven months and 13 countries, but I’m now happily settled on The Ophthalmologist, where I’m busy getting stuck into all things eyeballs.
