Genome editing has been evolving very quickly over the last couple of years, thank in large part to the CRISPR/Cas9 technique. With it, scientist are able to easily and precisely identify, edit or remove specific sections of DNA, allowing them to target specific mutations. This specific targeting of DNA sections gives great hope for curing inherited diseases. Now, researchers have used it to target HIV and remove the virus from infected cells.
How HIV Works
When the HIV virus infects someone, its RNA gets transcribed into HIV-1 DNA. That HIV-1 DNA then gets integrated into the CD4+ T-cells which are very specific immune response cells. These infected cells then replicate the HIV genome, making more of the virus and the cycle perpetuates itself. This process weakens the immune system which eventually gives rise to AIDS. Once the infection reaches this point, normally mundane infections become almost impossible for the body to fight off.
Current Treatment of HIV
The current treatment focuses on preventing the virus from infecting cells with antiretroviral drugs. With this, early detection of the HIV virus is crucial to a successful outcome. Once the virus has placed the DNA inside of the T-cells, little can be done.“Antiretroviral drugs are very good at controlling HIV infection,” explains Kamel Khalili, senior investigator of the study published in Scientific Reports. “But patients on antiretroviral therapy who stop taking the drugs suffer a rapid rebound in HIV replication.”
The researchers from Temple University decided to take a different approach by using CRISPR to locate and remove the sections of HIV-derived DNA from infected T-cells. They were able to remove the entire HIV DNA sequence with affecting the host cells. These T-cells were also immune to the infection after the DNA was removed.
“The findings are important on multiple levels,” says Dr. Khalili. “They demonstrate the effectiveness of our gene editing system in eliminating HIV from the DNA of CD4 T-cells and, by introducing mutations into the viral genome, permanently inactivating its replication. Further, they show that the system can protect cells from reinfection and that the technology is safe for the cells, with no toxic effects.”
The research was conducted on CD$ T-cells taken from HIV-infected patients and then grown in the lab. Hopefully this will give rise to a cure for HIV.