Hope for people with cataracts, new method reduces risk of rejection
Researchers have now succeeded in artificially producing a human cornea (cornea in the eye). The scientists grew the cornea from induced pluripotent stem cells. This new method could perhaps replace the damaged eye lenses of cataract patients.
When people get cataracts, they suffer a slow, painless loss of visual acuity. In most cases, such a damaged lens can then be surgically replaced with an artificial implant. Scientists have now developed a method for growing new human corneas from stem cells. The scientists published the results of their work in the journal "Nature"
New method could make artificial implants unnecessary
Physicians have now succeeded in growing a human cornea from induced pluripotent stem cells. Thus, in the future, cataract patients could perhaps get a new artificially grown cornea to be able to see properly again, the researchers say. Perfectly functioning cornea and lenses must be absolutely transparent. Sometimes, however, they become opaque (not transparent) due to illness or age. Such parts of the body then have to be replaced by artificial implants, the doctors explain. However, the processes used for this involve their risks. In some cases, the implants are rejected by the recipient's body. In such cases, stem cells could offer new hope for those affected. These are taken from the patient's own body, which limits the risk of rejection, the doctors add.
Scientists developed a new method to remove damaged eye lenses
Stem cells are primitive cells that become different specialized cells. These then form our various organs. Until a few years ago, there was only one way to obtain stem cells, which had to be taken from human embryos, the doctors explain. A very controversial practice, because it required the destruction of the embryo. But now scientists have developed induced pluripotent stem cells, which consist of old cells that revert to an earlier, more versatile state, the experts explain. Scientists from the United States and China developed a new way to remove a damaged eye lens. This could replace the clouded lenses in people with cataracts. The current surgical method leaves a large incision that can easily catch fire, say medical professionals. In the new process, a team extracts the damaged lens through a much smaller hole. Then naturally occurring stem cells are stimulated to construct a new lens. The method was already successful in rabbits and macaques, and was later used in twelve human children, the scientists add.
Cataracts are the most common cause of blindness in the world
Cataracts are the leading cause of blindness in the world. Every year, more than 20 million cataract patients are treated worldwide. However, the current process accidentally destroys the integrity of the lens capsule and the so-called LECs, which contain the regenerative key to restore the lens, the experts say. We have developed a new, minimally invasive surgical procedure that enables the regeneration of a functional lens, the experts add. In another study, researchers in Japan and Cardiff attempted to create induced eye cells from induced pluripotent stem cells, which they grew into a healthy cornea in a laboratory and then implanted in rabbits. So far, the doctors say whether one of the two therapies will ensure that the cornea or lens transparency is retained in the long term. (As)