实验动物,遗传性失明 z-bio 2021-06-11 513

　　A study by the Cedars-Sinai Medical Center in the United States proved for the first time that a new technology to treat genetic diseases by removing genetic defects can prevent retinal degeneration in some hereditary blind rats.

　　The research team of the Governor’s Institute of Regenerative Medicine at Cedars-Sinai Medical Center focuses on hereditary retinitis pigmentosa, a degenerative eye disease that can lead to blindness. There is currently no cure. Researchers use a technology called CRISPR/Cas9 to eliminate genetic mutations that can cause blindness. CRISPR/Cas9 is based on the strategy used by bacteria to fight invading viruses. Although rats were used in this study, the results of this study are an important milestone because they can affect humans.

　　Relevant research results were published in "Molecular Therapy" pointed out by Wang Shaomei (transliteration, Wang Shaomei), the first author of this study, research scientist of the Institute's ophthalmology project, and associate professor of biomedical sciences. With further development, this gene editing technology can be used to treat patients with hereditary retinitis pigmentosa. Dr. Shaomei Wang graduated from Liaoning Medical University in his childhood, and later received a master's degree and a doctorate degree from China Medical University. From the University of Sheffield, we focus on retinitis pigmentosa and optic nerve. Cell therapy for pathological changes, stem cell mechanism to repair vision, and immune response of human cells in the eyes of animal models.

　　According to data from the National Institutes of Health, patients with retinitis pigmentosa develop night blindness in the early stages of the disease, accompanied by retinal atrophy, pigmentation changes, decreased vision, and eventually blindness. Although relatively rare in general, it is the most common inherited retinal disease, affecting 1 in 4,000 people in the United States and Europe. Scientists at Cedars-Sinai Medical Center used CRISPR/Cas9, a technique for retinitis pigmentosa, which was used by genetic researchers in less than five years. It revolutionized the science of gene editing, making the genome editing process easier, more reliable, and cheaper.

　　This technology is a system adapted from bacteria to fight invading viruses. The bacteria first copy the genetic code of the invader into a specific ribonucleic acid (RNA) sequence. When the virus returns, the RNA binds to a protein called Cas9 and guides it to match the virus' genes. Protein can suppress genes. By modifying this system, scientists can program Cas9 to turn selected genes on or off, or rewrite their genetic code.

　　In this study, researchers at Cedars-Sinai Medical Center designed a CRISPR/Cas9 system to eliminate genetic mutations that cause the loss of photoreceptor cells in the eye. They injected the system into young experimental rats that were modified to mimic hereditary retinitis pigmentosa, called autosomal dominant inheritance, which contained mutations in this gene. By measuring the visual motor reflex, including moving the head in response to stripes of different brightness after a single injection, the researchers found that these rats had better vision compared to the control group.

　　Dr. Clive Svendsen, co-author of this study, said that modifying the components of the CRISPR/Cas9 system and using new viral vector technologies can improve the validity and consistency of these results. He believes that in the future, after further research, reliable genome editing of this system can provide a means to correct various genetic diseases.

　　Governor Svensson, Director of the Governor’s Institute for Regenerative Medicine, said: “This is the first time that CRISPR/Cas9 gene editing has been used to prevent vision loss in living animals. This is undoubtedly a surprise for more exciting and future research. As a result. It paved the way for clinical transformation."