CRISPR,HIV感染的预防和治愈 z-bo 2020-10-21 343

　　CRISPR is the most respected genome editing technology recently. It can efficiently and accurately edit almost all sequences in the genome, which will greatly promote disease research and the development of new therapies. The well-known scientific journal "Cell Reports" recently released a new result. Scientists used the CRISPR/Cas9 gene editing system to perform special editing and analysis on 45 genes related to HIV invading the host in human immune T cells, and identified one of them. After these genes have been edited and transformed, they can protect T cells from the invasion, integration, and transfection of the HIV virus. This is of great significance for the complete elimination of HIV virus, prevention and cure of AIDS.

　　The full name of HIV virus is human immunodeficiency virus. After HIV infects the human body, it invades and destroys CD4-positive T lymphocytes, leading to the continuous decline of immune system function, making the patient more and more vulnerable to a large number of other infections and diseases and eventually death. AIDS is a public health problem all over the world. According to WHO statistics, the global HIV-infected population approached 40 million in 2014, of which 2 million were newly infected. Due to the continuous progress of antiviral therapy in recent years, especially after the advent of the "cocktail" therapy combining multiple antiviral drugs, AIDS can be effectively controlled for a long time and has gradually become a chronic and controllable disease. However, the existing therapies have not been able to completely eliminate the HIV virus in the body, and are easy to relapse. How to completely eliminate the latent residual HIV virus in the body and how to prevent T cells from being reinfected by HIV are important problems in the treatment of AIDS today.

　　Previously, scientists have discovered that certain genetic mutations can protect T cells against the invasion of HIV virus, but this has not inspired more breakthrough methods to prevent HIV infection. The results of CRISPR technology to block HIV infection reported since 2013 are mixed, especially the report that HIV has developed resistance to CRISPR genome editing technology.

　　In this regard, scientists at the University of California, San Francisco and the Gladstone Institute have made breakthroughs. They built a special CRISPR/Cas9 genome editing system and imported it into T cells to complete the target gene editing work. They performed 149 special CRISPR/Cas9 genome editing operations in thousands of T cell samples from healthy volunteers. After each edit, they analyzed whether T cells with specific mutations after editing could resist HIV infection. They finally discovered that after editing several genes with mutations, T cells can completely or partially resist HIV infection. Such protective specific mutations include CXCR4, CCR5, LEDGF and NUP153.

　　The CCR5 gene has been shown in human clinical trials conducted by Sangamo Biosciences. After CRISPR editing to obtain protective mutations, it can reduce the HIV viral load in patients, and even in some patients not taking anti-HIV drugs, the virus The capacity can also be maintained at a low level.

　　Sangamo Biosciences vice president of research and development, Dr. Michael Holmes, said that in addition to the CCR5 gene, whether the other protective mutations found in CRISPR/Cas9 can benefit from human trials is unclear. But the results of this UCSF study are very gratifying and provide more potential HIV treatment targets. Judging from the current data, CCR5 and CXCR may be relatively ideal targets. Of course, it does not mean other protective mutations. Is worthless. The direction of the researchers' efforts is to use gene editing technology to edit multiple genes to obtain protective mutations, so as to truly better prevent and cure AIDS.