Photo Courtesy of NIAD via Flickr
By Helen Gloege ’23
Staff Writer
In June 1981, a “virus that attacks cells that help the body fight infection,” later identified as human immunodeficiency virus, or HIV, was first reported in the United States, according to the HIV.gov website. It has been about 40 years since the first cases of HIV were reported. UNAIDS estimated that in 2020, there were approximately 37.7 million people around the world with HIV and around 680,000 acquired immune deficiency syndrome-related deaths. There is currently no cure for HIV, but advancements in medical science have made it so that people living with HIV can control the impact of the disease on their body as well as its transmission rates.
On Feb. 15, 2022, a middle-aged woman was pronounced cured of HIV through a new method of treatment, according to Healthline. The new method of treatment came about when her doctors aimed to treat the woman for leukemia and HIV, according to The Smithsonian. The method of treatment included transplant of umbilical cord stem cells that contained a genetic mutation that would allow the blocking of HIV infection, The Smithsonian reported. According to the article by Reuters, this case is part of a larger study “led by Dr. Yvonne Bryson of the University of California Los Angeles, and Dr. Deborah Persaud of Johns Hopkins University.” The treatment for leukemia used “chemotherapy to kill off the cancerous immune cells,” at which point doctors provided the woman with a transplant of stem cells with the CCR5 mutation. The CCR5 mutation is a genetic mutation that prevents HIV from entering immune cells, according to Nature. Since receiving the transplant in 2017, the woman “has been in remission from her leukemia for more than four years,” according to The Guardian. Reuters also reported that the woman has been free of HIV for 14 months prior to the announcement.
Currently, the main avenue of controlling the HIV’s effects is antiretroviral therapy, as described by the Centers for Disease Control and Prevention. HIV treatment aims to keep the viral load — the amount of HIV in someone’s blood — low, and CD4 cells high. CD4 cells, which are also called CD4+ T cells, “are white blood cells that fight infection,” as described by the U.S. Department of Veteran Affairs. The CDC reported that effective HIV medications keep the “viral load so low that a test can’t detect it.”
According to Healthline, there have been about five people who have been considered cured from HIV naturally or through medical intervention. Among the five, there are two women who were found to be naturally cured of HIV without significant medical interventions. The numbers also include two men, Timothy Ray Brown and Adam Castillejo, who “received bone marrow transplants from donors who carried a genetic mutation that blocks HIV infection,” according to Live Science.
The treatment that Brown and Castillejo received isn’t common, as bone marrow transplants can be very dangerous and risk the possibility of graft-versus-host disease where the “donor immune system attacks the recipient’s immune system,” according to Reuters. Furthermore, this method presents issues in medical equity as well. Successful matches for bone marrow transplants can be difficult to attain for people of color, as genetic compatibility is a major factor and, according to The Guardian, “the majority of donors in registries are of Caucasian descent.”
According to Healthline, the transplant stem cells from the newly discovered cure came from umbilical cord blood cells with the CCR5 mutation and stem cells from a half-matched infant donor. After receiving both of the transplants, the patient “left the hospital just 17 days after her procedure, without any signs of graft versus host disease,” according to LiveScience.
The transplants occurred in August of 2017 and the patient “stopped taking HIV medication in early April 2020,” as reported by the Wall Street Journal. Due to her doctors’ inability to safely monitor her progress during the initial COVID-19 pandemic wave, she went back on HIV medication 10 days later, but then “went off the medication for good later that year,” according to the Wall Street Journal. According to The Smithsonian, the woman “has now been free of the virus [HIV] for 14 months.”
The use of umbilical cord blood aided in the success of the procedures. According to Your Genome, umbilical cord blood contains stem cells that can “develop into specialized cell types in the body.” According to The Smithsonian, umbilical cord blood is “collected at the time of a baby’s birth and donated by parents,” in a far easier donation process than that of bone marrow, as “the cells “don’t need to be matched as closely to the recipient as bone marrow donors.” NBC News explained in an article that the “cord blood is more adaptable, [and] generally requires less of a close HLA match” to treat cancer and cause fewer complications. The cord blood doesn’t “yield enough cells to be effective as a cancer treatment in adults,” which is why it was supplemented with additional stem cells, according to NBC News.
Despite the project’s success, it is unlikely to become a common practice for treating people with HIV. Healthline quoted Dr. Ronald Collman, the director of Penn Center for AIDS Research, saying, “Everybody agrees that stem cell transplants for [an] HIV cure is not a way forward unless the person needs it.”
Despite the potential risks, Dr. Koen van Besien, a doctor involved in the study, estimated that “there are approximately 50 patients per year in the U.S. who could benefit from this procedure,” especially those who may have other medical issues such as leukemia, according to The Guardian. Even if this treatment form can’t be applied on a mass scale, it provides “a roadmap for doing this using a person’s own cells” and additional help for researchers trying to develop “gene therapies to confer the HIV-resistant mutation to patients,” according to the Wall Street Journal.