New therapy holds promise for restoring vision in Retinitis Pigmentosa and Leber Congenital Amaurosis

Scientists from the University of California, Berkeley and Lawrence Berkeley National Laboratory, along with those of University of Pennsylvania, have demonstrated restoration of visual function in animal models that can help restore sight in blind patients afflicted by diseases such as Retinitis Pigmentosa (RP) and Leber Congenital Amaurosis (LCA).

Gene therapy for childhood blindness

Genzyme has announced the establishment of a research collaboration with the University of Florida (UF) and the University of Pennsylvania to develop gene therapy for the treatment for Leber congenital amaurosis type 1 (LCA-1), which is usually diagnosed in children who are less than a year old, and patients remain severely visually impaired for the rest of their lives. This disease, which is the most common cause of childhood blindness, is a group of degenerative diseases of the retina caused by genetic mutations in one of 19 genes currently associated with the disorder. These genes encode proteins that play a variety of roles in the development and function of the retina, and a mutation in any one of them can cause visual impairment.

Being the person, not the 'blind' person...

"...The accompanist’s rapidly moving hands on the keyboard spark curiosity about the source of the prominent piano line. But curiosity may linger for those that notice he is not using sheet music. The pianist is Shane Dittmar, a freshman music education major, accompanying the Department of Performing Arts’ production “It Gets Better” last October. For more than four hours, Dittmar played an entirely memorized piano part in the back-to-back productions." from The Pendulum, Elon University's Student News Organization And for 18 years, Dittmar has been living with a disability. Dittmar is blind. Diagnosed with a genetic disease called Leber Congenital Amaurosis (LCA), Dittmar and his twin brother Derek have been blind since birth. Just like Dittmar had to memorize music measures for “It Gets Better,” he has had to memorize innumerable daily methods in order to adjust to life being blind.

Shane has also been trying out musical theatre.

from The North Raleigh News With a flash of casting instinct from the mind of a high school theater director, Shane Dittmar has claimed his home on stage - the musical theater stage, that is. That's not necessarily an unusual thing for a high school sophomore who is a perfect-pitch tenor with a charismatic personality - punctuated by an enviable wit and outstanding student achievement honors. Difference here: Shane is blind.

Some of Shane's videos...enjoy his voice, his music and his wit!

Success in clinical trial brings researchers closer to cure for blindness

Researchers at Hadassah Hospital in Israel, led by Dr. Eyal Banin, have completed a clinical trial that tested the use of gene therapy to restore sight to patients suffering from Leber's Congenital Amaurosis (LCA). Dana and Yossi, two participants in this study, suffer from Leber's Congenital Amaurosis (LCA), the most severe form of all inherited retinal dystrophies causing congenital blindness. Like others affected, they have experienced severe visual impairment since birth. LCA sufferers experience poor night vision, low visual acuity and a constricted visual field. This low vision continues to deteriorate, leading to total blindness. Other symptoms may include crossed eyes, roving eye movements, unusual sensitivity to light, and/or cataracts. LCA is usually inherited as an autosomal recessive genetic condition. Those with LCA suffer in darkness, without sight and without hope. Until now.

Dr. Eyal Banin, MD, Ph.D., at the Center for Retinal and Macular Degeneration at Hadassah University Medical Center, in collaboration with leading researchers in the United States and Great Britain, performed a clinical trial that has successfully demonstrated the efficacy of gene therapy in the treatment of LCA.  LCA is caused by a mutation in the RPE65 gene.  In this clinical trial, a normal RPE65 gene was injected into the retina to replace the damaged gene and renew protein production. Participants Dana and Yossi were treated with this gene therapy in just part of the retina of one eye, with dramatic results. Shortly after treatment, both participants noted a substantial improvement in their vision.

When asked about the results of this treatment, Yossi said, "I felt the real change, the real revolution, after 21 days. It was amazing because today I see things that I have never seen before. I'm very proud to be a part of this research." Dana said, "Learning of new treatment was a life-changing event. I'm experiencing a real change. I was surprised to see real improvement in my vision."

Yossi and Dana's self-reporting of visual improvement is corroborated by objective, quantitative measurements of the treated area that also show significant improvement. With the continuation of this research, these scientists will be able to develop gene therapy to treat additional retinal degeneration diseases and make it possible to treat many more patients.

To watch a just-released video with more information about this clinical trial, its researchers and study participants, please visit http://www.mvrf.org/news.php.

Dr. Banin says: "You cannot imagine what an effect this has had not only on the treated patients, their families and on us, but also on the wider population of patients with retinal and macular degenerations here in Israel, who suddenly feel some glimmer of hope.."

Keith A. Lampman, Executive Director of MVRF, says, "We are extremely excited about the results of this study and feel confident that, in close collaboration with our partners across the globe, we are closer than ever to a cure for retinal diseases."

Source & Source

Stem cell treatment shows promise for Leber's Congenital Amaurosis (LCA) in animal trials

Approximately 200,000 children across the globe (and 12,500 in India) seem to be suffering from a kind of inherited childhood blindness known as Leber Congenital Amaurosis (LCA). It is assumed that light sensitive photoreceptor cells in the retina are forced to die in this disease which further leads to loss of vision. University College London Investigators have introduced a stem cell treatment that may replace diseased parts of the retina. This discovery can possibly promise future treatment for retinal diseases affecting several kids.

Scientists claim to have successfully implanted cells from healthy mice into mice with LCA. The implanted gene is believed to express a gene called Crx, vital for making healthy cone and rod photoreceptors. Having successfully merged with the retina, cells seemingly became new cone photoreceptors. Cone photoreceptors are key components for reading vision and colour vision.

This is the first time that researchers have demonstrated the possibility of transplanting new cone photoreceptors into mature retina. Recent research has shown that embryonic stem cells capable of self-renewal could provide an equivalent source of human cells that express the Crx 'photoreceptor-creating' gene and could be grown in the lab before being transplanted in the retina.

The research highlights that it may be possible to treat a disease such as LCA by photoreceptor cell transplantation via use of stem cells. It may also be possible for treatment intervention at various stages of the disease, which increases the chances of treatment for more number of patients.

LCA has been a disease of focus as one of the only two diseases in medicine that has shown significant improvement with gene therapy treatment. This study demonstrates success for treatment of LCA in animal trials. But more studies will need to be performed, since stem cell derived cells need to demonstrate that they have lost the capability of further division and differentiation. Further investigations are needed to demonstrate possibilities of restoring sight with this newly developed treatment.