Treating a Cloudy Cornea with Stem Cells
Research in mice suggests that using cell therapies to remove scarring on the cornea that clouds vision might actually be a comparatively simple process:
Treating the potentially blinding haze of a scar on the cornea might be as straightforward as growing stem cells from a tiny biopsy of the patient's undamaged eye and then placing them on the injury site, according to mouse model experiments conducted by researchers. "The cornea is a living window to the world, and damage to it lead to cloudiness or haziness that makes it hard or impossible to see. The body usually responds to corneal injuries by making scar tissue. We found that delivery of stem cells initiates regeneration of healthy corneal tissue rather than scar leaving a clear, smooth surface."[Researchers] had previously developed a technique to obtain ocular stem cells from tiny biopsies at the surface of the eye and a region between the cornea and sclera known as the limbus. Removal of tissue from this region heals rapidly with little discomfort and no disruption of vision. After collecting biopsies from banked human donor eyes, the team expanded the numbers of cells in a culture plate. They conducted several tests to verify that they these cells were, in fact, corneal stem cells.
The team then tested the human stem cells in a mouse model of corneal injury. They used a gel of fibrin, a protein found in blood clots that is commonly used as a surgical adhesive, to glue the cells to the injury site. They found the scarred corneas of mice healed and became clear again within four weeks of treatment, while those of untreated mice remained clouded. "Even at the microscopic level, we couldn't tell the difference between the tissues that were treated with stem cells and undamaged cornea. We were also excited to see that the stem cells appeared to induce healing beyond the immediate vicinity of where they were placed. That suggests the cells are producing factors that promote regeneration, not just replacing lost tissue."
Could this same technique be used to cure bad vision, most notably farsightedness?
In LASIK (which is an excellent idea if your eyes are as horrible as mine were: -10.5 diopters to nearly 20/20 vision in both eyes), corneal tissue is vaporized. Unfortunately, this also destroys nerves, leading to dry eyes and other minor problems.
Farsightedness is harder; the tissue needs to be totally reshaped to make a peak, because we have no current way of adding living tissue, which would be much more appropriate here.
Perhaps the technique of the near future for someone with a bad cornea will be to regenerate plenty of tissue, then use a laser to sculpt it into an appropriate shape.
@Slicer - given that the mean age of people in the US is now 36, there is clearly a huge upcoming market for any decent cure for age related farsightedness.
Perhaps a dissolving hydrogel plus these adult stem stems could be used in some way? Although part of the problem is that the lens becomes less elastic over time, perhaps due to the crosslinking of proteins?
I think this falls into the "engineering small body parts with stem cells category" along with new teeth and hair follicles.
Does it mean a viral scarring too handle this way . giving a clear cornea and is the initial results out .as far i read an initial trail is going on human
How many years take this technology be used in human. I have a corneal scar in my left eye that decreased my vision. My doctor said U should have a corneal transplant but I afraid of it. Because I Know it is dangerous. This scar was caused by after PRK tha is I had a post PRK keratitis. Does it cost to wait for this technology?
This must be available now? I need the top 3 layers of my cornea cured by this please