Some people diagnosed with HIV are able to eradicate the virus without antiretroviral medications or even stem cell transplants, possessing the ability to naturally suppress the virus and achieve a medically verifiable cure. Scientists call this small population elite controllers, a moniker that reflects their unique ability to keep one of the most notorious viruses at bay. Two of these patients have garnered fame in the scientific literature in recent months, each known mostly by a code name: the San Francisco Patient, and another called the Esperanza Patient. Both are women who have been spotlighted in medical journals and at scientific conferences for having eradicated HIV from their bodies. Beyond those two celebrated examples, new research from the Ragon Institute in Boston has zeroed in on a larger group of elite controllers – 58 altogether – who have also been able to keep the virus at bay by virtue of their distinct biological capabilities, reports Medical Xpress. The elite controllers were compared with 42 HIV patients on antiretroviral therapy, people who represent the vast majority of those diagnosed globally with HIV. Writing in Science Translational Medicine, immunologists at the institute report that they have uncovered a deep well of new clues that point to elite controllers’ unusual ability to eradicate the virus. One reason is a powerful immune response, but another centres on where latent viral genetic sequences are stranded in the human genome. These sequences tend to be tucked into chromosomes in remote regions where they are less likely to replicate, but more likely to be found by immune forces. The research is opening a new window of understanding into what it means to be infected with HIV, a virus that is estimated to affect 38 million people globally. Millions worldwide have died since the HIV pandemic began 40 years ago. Most patients take antiretroviral drugs for life to hold the virus in check, but elite controllers can handily subdue HIV for long periods without the need for medications. Although the San Francisco Patient was infected in 1992, she has kept the virus at bay for decades. Her existence – and that of other elite controllers – defies the long-held dogma that HIV infection is invariably for life. The new findings join a growing body of work that may eventually lay the groundwork for future pharmaceutical interventions to help the vast majority of HIV patients eliminate the virus based on principles scientists are learning from elite controllers, people who have achieved so-called “sterilizing cures.” “Increasing evidence suggests that durable drug-free control of HIV-1 replication is enabled by effective cellular immune responses,” lead author, Dr. Xiaodong Lian wrote along with his colleagues. Lian and other members of the team studied what they call the subtle “footprints” of the immune system that reveal how elite controllers are able to eliminate HIV infection without medication. Data from their experimental work suggest that viable human immunodeficiency viruses in elite controllers may face greater pressure from immune system cells. As a result, the viruses are unable to dodge the immune system’s formidable army.