For nearly half a century, researchers have battled to find a curative treatment for HIV. Along the way, many groundbreaking therapies and medications have been identified. But while these treatments help people manage their infection fairly well, targeted cures against HIV remain elusive. Based on recent discoveries, however, that may be about to change in the near future. Using gene editing technology, scientists have been able to develop better strategies that may actually eradicate HIV infections. They are therefore quite hopeful that gene editing therapy for HIV may be the way of the future.
For several years now, researchers have tried to use gene editing therapies for HIV without much success. Their goal was to boost a person’s immune system by placing key gene sequencies within immune system white blood cells. While some were successful in achieving this, their success only occurred with white blood cells in the lab. Efforts to use gene editing technology to alter immune cells in the body proved challenging. But this is where some scientists have made some important gains. If immune cell changes can be produced within a person infected with HIV, the potential for an actual cure is much greater. And these same technologies and strategies could help treat many other conditions as well.
“Until now, only a few scientists, and we among them, had been able to engineer B [white blood] cells outside of the body, and in this study, we were the first to do this in the body and to make these cells generate desired antibodies.” – Adi Barzel, Researcher in Biochemistry and Molecular Biology, Tel Aviv University
How Gene Editing Therapy for HIV Works
To explain gene editing technology used by the researchers, it’s important to appreciate the challenges associated with HIV. The HIV virus itself poses many difficulties when trying to develop a cure. For one, it hides within immune cells, making it difficult for immune cells to target the virus. Likewise, the HIV virus rapidly changes or mutates, which means a single antibody against HIV won’t be very effective for long. This is why vaccines have been less than ideal against HIV. Understanding this, scientists need to create an immune cell that produces a broad range of antibodies against HIV. And this is where gene editing therapy for HIV treatment has been proposed as an option.
For years, researchers have tried to add gene sequences to B cells so they may produce broad neutralizing HIV antibodies. Using gene editing technology called CRISPR, they can cut B cell genes and add other genes known to produce the types of antibodies they want. However, prior to now, this has only been accomplished in a lab outside a test animal. While this process might be used to develop HIV treatments, the costs and equipment required to do so isn’t feasible. Therefore, the goal has been to use gene editing therapy for HIV by altering B cells within the test animal. This is where recent breakthroughs have been made, resulting in the production of broad, neutralizing antibodies against HIV in mice.
“When the CRISPR cuts in the desired site in the genome of the B cells, it directs the introduction of the desired gene, the gene coding for the antibody against the HIV virus.” – Alessio Nehmad, PhD Student in the School of Neurobiology, Biochemistry and Biophysics, Tel Aviv University
An Innovative Approach and Breakthrough
The recent breakthrough concerning gene editing therapy for HIV involved the use of another virus. Adeno-associated viruses are common, but they trigger minor if any immune responses in human beings. They are also easily programmed from a genetic perspective, and they can target specific cells for gene editing. Understanding this, scientists at Tel Aviv University used two adeno-associated viruses as part of their gene editing technology. The first virus targeted B cells in mice and used CRISPR to cut a specific gene region. The second virus then placed genes known to produce broad neutralizing antibodies against HIV. The end result produced B cells capable of ramping up production of huge amounts of the anti-HIV antibodies.
The use of these adeno-associated viruses, known as virus vectors, is what allowed B cells to be changed within the mice. This makes gene editing therapy for HIV much more plausible from a practical perspective. Plus, when the scientists test these B cell responses against HIV, they found them to be very effective in neutralizing HIV infection. As a result, they believe this approach is not only safe and effective but also highly scalable. In other words, this gene editing technology approach can be developed for widespread use with relative ease. As a result, it offers much greater promise for curing HIV infection after acquired when compared to existing medication treatments.
“We developed an innovative treatment that may defeat the virus with a one-time injection, with the potential of bringing about tremendous improvement in the patients’ condition.’” – Adi Barzel
A Much Greater Potential Beyond HIV Treatment
At the current time, the gene editing therapy for HIV has only been successful in the lab and with mice. More research and experiments are therefore required before human trial testing might be feasible. However, the results are extremely promising based on the current level of success. The ability to alter B cell function and response in the body paves the way for gene editing technology use for other infections as well. While this will not replace novel mRNA vaccines, it could well invite much more effective viral treatments long-term.
It is also worth noting that this same gene editing therapy for HIV could be used for other disorders besides infections. Specifically, the researchers at Tel Aviv University suggest that similar strategies could be used against cancer and autoimmune illnesses. By using gene editing technology to change immune cell responses, more specific therapies for these conditions might develop. Given this potential, these recent breakthroughs may be more important than previously realized. If so, the next few decades could usher in a completely new way of fighting disease in a much more comprehensive way.