基因疗法,失明者 z-bo 2020-09-19 415

　　The visual pathway in the brain is made up of millions of interconnected neurons. When sensory signals are sent, the connections between neurons become very strong. If sensory signals are not used, such as loss of vision, the connections of neurons will become weak and confused.

　　In the past few years, a gene therapy that injects healthy genes into the eye to repair mutations has become the most potential treatment for congenital and degenerative blindness.

　　The first trial of gene therapy to treat blindness was in 2007. The subjects were 10 volunteers with Reber's congenital melanopathy. The genetic disease caused retinal degeneration and total insomnia. The study found 10 volunteers The PRE65 gene of the patients had mutations. The research test injected a harmless virus into the eyes of subjects. The viral vector carries a normal copy of the RPE65 gene.

　　Regain the vision

　　After receiving the treatment, some subjects began to see clearly the fingers waving in front of their eyes, and could even read the six lines of information on the chart. Other subjects were able to perform obstacle crossing training under dim lighting.

　　Manzar Ashtari and her colleagues at the University of Pennsylvania in Philadelphia wanted to learn more about the reasons for the recovery of the visual pathway after the subjects received treatment. Two years after the subjects received treatment, Manzar Ashtari asked them to return to the laboratory for brain scans. It turns out that the visual pathway of the treated eye looks very similar to that of the normal eye, and even stronger than the visual pathway of the treated eye.

　　The research team expects to see changes in the brain of the subjects, and the results are somewhat surprising. Ashtari said that the age of the subjects should be considered. In this trial, most subjects were around 20 years old, and only one was 45 years old. From the perspective of age, the team found a more important conclusion!

　　Vision is something worth striving for

　　There is a general consensus that early life is a critical period for neuron shaping, repair and remodeling. This plasticity decreases with age. Ashtari said there may be an optimal period for the acceleration of brain plasticity, but their research shows that adults have not lost the ability to reorganize visual pathways.

　　However, the problem is that people doubt whether this gene therapy will affect the brain pathways when repairing retinal cells, which will prevent people from perceiving the visual signals that the gene therapy cannot start. In addition, if people's vision degeneration leaves some sequelae, gene therapy can only bring them some limited vision.

　　The team is applying to the FDA for this gene therapy to treat Reber's congenital melanopathy. Eric Pierce, an ophthalmologist at Harvard University School of Medicine, also agrees that the results of the test show that the adult visual system may also be plastic. He once believed that the damage to the brain and nervous system of adults is irreversible. Pierce said the results of this study are important, as it at least reveals that nerve remodeling can improve subjects' vision. Gene therapy repairs damaged cells in the eye while adjusting the brain to process new information. This is really killing two birds with one stone.