Gene therapy discovery triggers hope for glaucoma patients

Key Takeaways

• Overproduction of a protein called tau in the retinas of mice led to degenerative changes like those seen in glaucoma.
• A novel gene therapy that brings tau levels down to a healthy level provided protection from these degenerative changes, suggesting that targeting tau could be a promising therapeutic strategy.

The protein tau is essential to the function of cells in the brain and central nervous system, but when overproduced under certain conditions, it forms tangles that clog the cells’ internal structures. These tangles have also been found in Alzheimer’s disease patients. Tau is also present in neuronal cells in the retina, and research led by Macquarie University’s Vision Science Group has found that altered tau is likely to have a significant role in the development of glaucoma.

In the Vision Science Group’s latest study, published in Acta Neuropathologica Communications, the team manipulated tau levels in the retinas of mice using a novel gene therapy. “We have shown that tau is vital to maintaining retinal integrity, but it is a delicate balance,” says Associate Professor Vivek Gupta, who led the work. “There is what you might call a ‘Goldilocks’ zone, where tau levels are just right, and that promotes optimal retinal health. When we over-produced tau, we observed inner retinal degeneration, but when there was too little tau, that was also detrimental.”

The researchers further found that “switching off the over-production and knocking the tau down to healthy levels provided protection against the degenerative changes associated with glaucoma. While it was not able to restore lost vision, it did stop the retinal degeneration from worsening. These findings highlight the critical role of tau protein in retinal health, and suggest that targeting tau could be a promising therapeutic strategy for glaucoma, particularly when administered early.” 

The paper’s lead author, Dr. Thananthirige, says the team’s ultimate goal is to develop a gene therapy to use in tandem with treatments that lower intraocular pressure after glaucoma is diagnosed. The next step will involve further testing in animal models, with human clinical trials still several years in the future.

Edited by Suditi Kedambadi and Miriam Kaplan, PhD.

Source: Georgia Gowing, Macquarie University, Medical Xpress, July 23, 2024; see source article