Combination therapy of hereditary color blindness
Scientists at Michigan State University, working under the guidance of Associate Professor Andras Komaromy, based their research on the results of earlier work. In 2010, with the help of gene therapy, they managed to restore daytime vision in dogs suffering from achromatopsia – a hereditary form of color blindness – by replacing the mutant form of the gene associated with this disease.
The technique gave good results in most young dogs, but did not have the desired effect on animals over the age of 1 year. The researchers suggested that the reason for this is the degeneration of non–functioning cones - photoreceptor cells of the retina that perceive color information. To overcome this problem, they decided to try to selectively destroy the photosensitive components of cells and allow them to recover before using gene therapy.
Scientists injected dogs with achromatopsia, aged 1-3 years, with a protein known as ciliary neurotrophic factor (CNTF). This protein is synthesized by the central nervous system to maintain the health of nerve cells. In sufficiently high doses, it partially destroys photoreceptors, stimulating their self-healing.
The researchers' expectations were met – all seven animals that underwent the introduction of ciliary neurotrophic factor and subsequent gene therapy, regardless of age, responded to treatment, which was not observed in control group dogs.
According to Komaroma, achromatopsia is quite rare, but it is a good model for studying other diseases that affect photoreceptors and are one of the leading causes of incurable blindness in dogs and humans. The mechanisms of development of such diseases in representatives of both species are very similar to each other, so Komaromy believes that the developed two-stage approach can form the basis of a new concept for the treatment of retinal diseases in humans.
The head doctor (left) and one of the patients (right :)Article by Andras M Komaromy et al.
Transient Photoreceptor Deconstruction by CNTF Enhances rAAV-Mediated Cone Functional Rescue in Late Stage CNGB3-Achromatopsia is published in the journal Molecular Therapy.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of Michigan State University:
One-two punch could be key in treating blindness.
10.04.2013