Stem-Cell Coated Contact Lenses Could Cure Blindness
Scientists at the University of Sheffield have developed a new “contact lens” loaded with stem cells that has the potential to naturally repair sight. Using a series of complex techniques, the researchers were able to create a disc of biodegradable material that can be fixed over the cornea. The disc is coated with stem cells that then multiply within the eye. Once they have recolonized, these unique cells begin to actually repair the damaged eye, allowing it to heal naturally.
But what exactly are stem cells? Stem cells are the building blocks of tissue growth – special cells found in all multicellular organisms that have the ability to, through mitotic division, transform into any other type of cell in the body. That means that these cells have the potential to repair a variety of organs and tissues aside from injured eyes, such as hearts and brains.
Three patients, each previously blind in one eye, have already had their sight restored in less than a month through these new lenses. The researchers simply extracted stem cells from their working eyes and cultured them in contact lenses for 10 days. Within two weeks of use, the stem cells began recolonizing and repairing the cornea. They have already seen significant change in their vision – two of the patients, who were legally blind, can now read the larger letters on an eye chart, while a third patient, who was nearly blind, can pass the vision test needed for a driver’s license.
The main part of the eye that will be targeted by the lenses is the cornea, the transparent layer on the front of the eye where most cases of blindness are found from corneal damage. Examples of corneal damage include injuries to the outermost layer of the transparent tissue, damage or scars from other eye surgeries, infections, hereditary corneal defects, and inflammation from chronic dry eye.
A major feature of the new disc is that it contains small pockets to house and protect the stem cells, keeping them grouped together and within the eye. “The disc has an outer ring containing pockets into which stem cells taken from the patient’s healthy eye can be placed,” said Dr Ílida Ortega Asencio, from Sheffield’s Faculty of Engineering. The researchers said another advantage of the disc is that it is biodegradable and made from the same material already used in surgical stitches, so it will not adversely affect the body.
Laboratory tests have already proven that the membranes will support cell growth. As a result, clinical trials are expected to begin shortly inIndiaat the LV Prasad Eye Institute in Hyderabad. Plus, the simplicity and fairly low cost of the procedure could make it available in poorer areas.
It’s hoped the implant will help millions of people across the world regain one of life’s most precious gifts – sight.
