On the long road to defeat AIDS, mankind has taken another small step. Scientists at the University of California, San Francisco recently used gene editing technology to successfully cultivate white blood cells that can fight HIV infection with induced pluripotent stem cells (iPS cells). In addition to white blood cells, this iPS cell can also be grown into other types of blood cells. The researchers said that this strategy is expected to become a new method of functional cure for AIDS.
Previous studies have found that HIV tends to attack a cell called CD+4 T by locking the CCR5 protein in the patient’s body to destroy the human immune system. However, this infection process affects a small number of Europeans. Progress is extremely slow. The reason is that the gene related to CCR5 in his body has been mutated, resulting in a copy called CCR5Δ32. People with this mutant gene have natural resistance to HIV. After obtaining this discovery, scientists will naturally think of using stem cell transplantation to transfer this mutant gene into the body of AIDS patients to achieve the goal of curing AIDS.
A well-known example is the world’s first and only AIDS patient cured so far-Timothy Ray Brown. The 48-year-old American was diagnosed with HIV in 1995 and was diagnosed with acute myeloid leukemia in 2006. But after two bone marrow stem cell transplant operations, he miraculously recovered, and there was no trace of HIV in his body. But unfortunately, Brown’s luck cannot be replicated. People with this mutant gene account for only 1% of Europeans. In addition to the huge medical expenses and the huge risk of transplantation, it is a small probability event to find a suitable bone marrow match that is "immune" to HIV.
The goal of the new research is to achieve the same effect without the need for CCR5Δ32 gene donors. Jian Yuewei, a Chinese geneticist at the University of California, San Francisco (transliteration), and his team used the third-generation gene editing technology CRISPR-Cas9 system to insert CCR5Δ32 gene fragments into ips cells and then cultivated them into white blood cells. Compared with traditional gene editing technology, the new technology is more efficient and more precise in the insertion position. The physicist organization network reported that Jianyuewei’s team has proven that the CRISPR-Cas9 system can effectively perform gene editing. The results of the experiment confirmed that the white blood cells they cultivated with the CCR5Δ32 gene fragment can indeed be protected from HIV infection.
The research is still in the experimental stage. Jianyuewei’s team has not cultivated these gene-edited iPS cells into special types of white blood cells such as CD+4 T. There are still many factors to consider in cell type conversion and transplantation, and there is still a long way to go before clinical application. But what is certain is that this result brings a new possibility for the treatment of AIDS.