The Cure: It Ain’t Gonna Happen Fast

At last month’s HIV Cure Conference in San Diego, Dr. David Margolis had unenviable role of pouring cold water on anyone’s heightened expectations. Margolis heads the Collaboratory of AIDS Researchers for Eradication (CARE), a collabortion with reasearchers from different parts of the country that is funded by the National Institutes of Health (NIH).

CARE co-hosted the San Diego based HIV Cure Conference with  University of California San Diego AntiViral Research Center.

 After updating the audience on how scientists involved in the CARE consortium are working together to leverage research and resources, Margolis talked about Timothy Brown, the “Berlin patient” cured of HIV with a bone-marrow transplant.

“Timothy Brown [has] probably been cured,” Margolis observed. “And that’s a wonderful thing. But there are close to 80 million people that’ve been infected around the globe over the last century. So one in 80 million is not great odds. What it is, is proof of a principle: that a cure is feasible.  But I want to manage expectations and convey the reality about this whole cure expedition, and that is: It ain’t gonna happen fast.” (Read why there isn't a cure yet here.)

In contrast to a vaccine, in which scientists target the human immune system, Margolis said “with the cure we’re not targeting our own genes, we’re targeting the virus’ genes. And we’re not sure which ones to target.”

This raises the possibility of what Dr Warner Greene, who also spoke at the Cure Conference called, “a new class of [HIV] therapeutics targeting the host rather than the virus." A Professor of Medicine Microbiology and Immunology at UC San Francisco, Greene spoke about how HIV actually causes our own immune systems to work against us.

Calling the search for a HIV cure “analogous to curing cancer,” Margolis said that figuring out what to target and discovering drug combinations that can hit those targets, “is going to take a long time."

It may require a series of treatments, similar to the series of injections that an in-development HIV vaccine would employ.

After 30 years working on HIV research, Margolis said some issues still impede the quest for a cure and one of those is being able to measure HIV reservoirs. We can currently find HIV in the bloodstream, but Margolis said, researchers have discovered that “what we can measure is just the tip of the iceberg.”

In fact, the stats are disturbing: Margoilis said that the HIV doctors are measuring is in the blood stream and yet “only one percent of T-cells” are located in the bloodstream. The remainder hides in tissues, where HIV also doesn’t behave the way it does in blood.

Greene's own research shows that 98 percent of the HIV-infected cells are in lymphoid tissue (like the spleen and tonsils) where it causes massive cell death in a process known as pyrotosis.

That HIV is able to hide from doctors means, Margolis said, the “absence of detection is not detection of absence,” and it makes eliminating HIV a difficult proposition. He added that even the brain may serve as an HIV reservoir, but joked that so far, “no [HIV-positive patient] has volunteered samples” of their brain.

For more info: Another HIV Cure conference speaker, Jerry Zach spoke about activating and eliminating those HIV reservoirs.