Gene therapy could completely defeat HIV
Photo: Julia PYKHALOVA
Doctors from the city of Düsseldorf in Germany announced the cure of a 53-year-old man from HIV, an article published in the journal Nature. Cured as a result of a rather risky operation: a blood stem cell transplant from a donor who has a genetic mutation that disables the CCR5 receptor. It is this receptor that HIV uses to infect immune cells.
Strictly speaking, curing HIV during such an operation is a kind of side effect, since the main goal here is the therapy of leukemia, an oncological disease of blood cells. However, the Dusseldorf patient stopped taking antiretroviral therapy in 2018. Until now, she has been under constant medical supervision and her HIV has not yet returned. This allows us to say that the remission stage has arrived. The history of HIV treatment knows several more cases. Two patients with a similar medical history are commonly referred to as “Berlin” and “London”. But is it possible to make this type of treatment for HIV infection affordable and ubiquitous? What are the scientific prospects for defeating HIV? KP.RU asked the immunologist, candidate of medical sciences, general director of the contract research company Nikolai Kryuchkov.
HOW THE DUSSELDORF PATIENT IS CURED OF HIV
In fact, the chemotherapy used to treat leukemia destroyed the patient’s own blood-forming cells. This destroyed his lymphocytes, important but not the only carriers of HIV. They were then replaced with new cells from a donor who was relatively immune to the human immunodeficiency virus.
– The probability of success with such therapy is far from one hundred percent. Many conditions must coincide here, including the patient himself must have prerequisites: already a serious oncological disease. In this case, we can take a chance, says Nikolai Kryuchkov. – The problem with curing HIV infection is that, in addition to the fact that the immune system itself is affected, the virus is also deeply integrated into the human genome. It is almost impossible to eliminate this problem later. But slowing down the process is successful. Here antiretroviral therapy works, which is very effective.
CAN THIS CASE BE USED TO HEAL PEOPLE WITH HIV?
A person infected with HIV is, in most cases, still quite young and relatively healthy at the time of infection. Antiretroviral therapy is virtually guaranteed to eliminate the possibility of HIV transmission at birth. A person can live stably for decades if he receives regular and comprehensive treatment.
– And here we will take it and offer to cure it not with a 100% chance, but in this case it will be necessary to completely kill its hematopoietic tissues. As a more accessible and scalable technology, this story is not suitable, says Nikolay Kryuchkov. – There are some successes, individual cases, this is good, but more long-term follow-up is required to understand that HIV will not really return to the patient.
WHAT IS THE PROSPECT OF A COMPLETE VICTORY OVER HIV?
HIV vaccine development
Unfortunately, recent large studies have shown little or no effectiveness of vaccines in preventing HIV infection in risk groups, among people suffering from chemical addictions. Work towards vaccines that generate an immune response, help fight disease, be more successful.
– I suppose that the future lies in the creation of complex vaccines against HIV, which will be used according to a complex vaccination scheme. They will somehow reduce the chances of getting infected and effectively slow down the course of the infection. But this will not be a complete cure, says Nikolai Kryuchkov.
Gene therapy has the potential to completely defeat HIV.
– If we talk about the use of gene therapy for the treatment of human diseases, we are still at an early stage of development of this technology, – notes the expert. – There is still a long way to go. It is not yet clear how to “select” HIV from the human genome so that the person himself does not die in this process or is not critically damaged.