Featured Research

from universities, journals, and other organizations

Sight restored to mice afflicted with retinitis pigmentosa

Date:
June 25, 2010
Source:
INSERM (Institut national de la santé et de la recherche médicale)
Summary:
Swiss researchers have just restored sight to mice afflicted with retinitis pigmentosa. The results have been confirmed ex-vivo, on human tissue cultures. Thanks to a complementary clinical approach, the team has now determined the types of patient who could benefit from this therapy.

Cross section of a degenerated Retinitis pigmentosa retina. The archaebacterial halorhodopsin is produced in the remaining cone photoreceptor cells (green). Only one row of photoreceptor cells is left. In white the nuclear layers of the retina.
Credit: Courtesy Friedrich Miescher Institute for Biomedical Research

Swiss researchers from the Friedrich Miescher Institute, in collaboration with Inserm researchers from CNRS and UPMC in the Institut de la Vision, have just restored sight to mice afflicted with retinitis pigmentosa. The results have been confirmed ex-vivo, on human tissue cultures. Thanks to a complementary clinical approach, the team led by Jose-Alain Sahel (Institut de la Vision/Centre d'Investigation Clinique) has now determined the types of patient who could benefit from this therapy.

Related Articles


Retinitis pigmentosa affects over one million people worldwide and is manifested by a progressive loss of sight, eventually leading to blindness. Retinitis pigmentosa is a form of inherited retinal degeneration that affects the light-sensitive cells : photoreceptors. Photoreceptors are a special type of neuron which convert light into nervous impulses. These impulses are then processed by the retina and transmitted along the nerve fibres to the brain. There are two types of photoreceptors: rods and cones.

As the disease progresses, it leads initially to degeneration of the rods which are responsible for night vision. Then the cones, which are responsible for diurnal vision, become affected. Whereas the rods are destroyed, the cones survive in the organism for extended periods, even after the occurrence of blindness as they cease to function. This inspired the researchers from the Friedrich Miescher Institute (FMI) and the Institut de la Vision to develop a genetic therapy to restore the visual function of the cones which were defective (dormant) but remained present.

Recreating a biological photoelectric system

At the stage of the disease where the researchers have intervened, although the defective cones no longer possess the ability to respond to a luminous stimulation (photo reception function) they do still retain some electrical properties and their connections with the neurons of the inner retina which normally transmit visual information to the brain. Hence, they are able to be activated artificially. Earlier work, carried out by the same team under the direction of Botond Roska (FMI), had shown that light-sensitive ionic channels, identified by the team of Ernst Bamberg (Max Planck Institute, Frankfurt), had the ability to modulate electrical activity from various neurons into which they had been introduced, in response to the level of light.

By combining these two observations, the researchers have succeeded in reactivating cones and thus allowing re-stimulation of the mice's ON/OFF transmission channels. To achieve this, they have introduced a protein, via a genetic therapy vector, which is capable of coupling luminous stimulation to ionic transport, hence reintroducing the phototransduction cascade required for vision. The researchers have therefore recreated a genuine biological photoelectric system.

These results are very promising, particularly as they have been confirmed by Serge Picaud and researchers at the Institut de la Vision using human retina in cultures and therapeutic vectors for which human compatibility has already been demonstrated. The photosensitive protein can be expressed in human cone photoreceptors to which it confers a new sensitivity to light.

"We integrated the clinical approach as soon as we obtained the first fundamental results of this work. So, at the national reference center for rare diseases of the retina, thanks to non-invasive high-resolution retinal imaging techniques, we can now target patients to whom this therapy could be applied" explains José Alain Sahel, who points out that the transition from mice to man always carries many uncertainties. " The results are also very complementary to the research which has been carried out at the Institute and the CIC by the team of Serge Picaud, which aims to test and improve an artificial retina as well as our research on RdCVF protein which protects the activity of cones ."


Story Source:

The above story is based on materials provided by INSERM (Institut national de la santé et de la recherche médicale). Note: Materials may be edited for content and length.


Journal Reference:

  1. Volker Busskamp, Jens Duebel, David Balya, Mathias Fradot, Tim James Viney, Sandra Siegert, Anna C. Groner, Erik Cabuy, Valerie Forster, Mathias Seeliger, Martin Biel, Peter Humphries, Michel Paques, Saddek Mohand-Said, Didier Trono, Karl Deisseroth, Jose A. Sahel, Serge Picaud, and Botond Roska. Genetic Reactivation of Cone Photoreceptors Restores Visual Responses in Retinitis pigmentosa. Science, 2010; DOI: 10.1126/science.1190897

Cite This Page:

INSERM (Institut national de la santé et de la recherche médicale). "Sight restored to mice afflicted with retinitis pigmentosa." ScienceDaily. ScienceDaily, 25 June 2010. <www.sciencedaily.com/releases/2010/06/100624144103.htm>.
INSERM (Institut national de la santé et de la recherche médicale). (2010, June 25). Sight restored to mice afflicted with retinitis pigmentosa. ScienceDaily. Retrieved October 25, 2014 from www.sciencedaily.com/releases/2010/06/100624144103.htm
INSERM (Institut national de la santé et de la recherche médicale). "Sight restored to mice afflicted with retinitis pigmentosa." ScienceDaily. www.sciencedaily.com/releases/2010/06/100624144103.htm (accessed October 25, 2014).

Share This



More Health & Medicine News

Saturday, October 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

IKEA Desk Converts From Standing to Sitting With One Button

IKEA Desk Converts From Standing to Sitting With One Button

Buzz60 (Oct. 24, 2014) — IKEA is out with a new convertible desk that can convert from a sitting desk to a standing one with just the push of a button. Jen Markham explains. Video provided by Buzz60
Powered by NewsLook.com
Ebola Protective Suits Being Made in China

Ebola Protective Suits Being Made in China

AFP (Oct. 24, 2014) — A factory in China is busy making Ebola protective suits for healthcare workers and others fighting the spread of the virus. Duration: 00:38 Video provided by AFP
Powered by NewsLook.com
WHO: Millions of Ebola Vaccine Doses by 2015

WHO: Millions of Ebola Vaccine Doses by 2015

AP (Oct. 24, 2014) — The World Health Organization said on Friday that millions of doses of two experimental Ebola vaccines could be ready for use in 2015 and five more experimental vaccines would start being tested in March. (Oct. 24) Video provided by AP
Powered by NewsLook.com
Doctor in NYC Quarantined With Ebola

Doctor in NYC Quarantined With Ebola

AP (Oct. 24, 2014) — An emergency room doctor who recently returned to the city after treating Ebola patients in West Africa has tested positive for the virus. He's quarantined in a hospital. (Oct. 24) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins