New research suggests that a cure for HIV/AIDS may be much further off than scientists believed, underscoring the need for different drug approaches.
In a report published Oct. 24 in the journal Cell, Johns Hopkins scientists uncovered another obstacle in the way of fighting the immune-compromising disease. The levels of potentially active, dormant forms of HIV hiding in infected immune T cells may be 60 times greater than previously thought. This so-called latent reservoir of functional proviruses is left behind after drug therapy with antiretrovirals has halted viral replication, stopping the course of the disease.
Senior study investigator Dr. Robert Siliciano said while most proviruses in the latent reservoir are defective, curing the disease will depend on figuring out how to target all proviruses that have the potential to resume the infection. The researchers found that if antiretroviral therapy is stopped or interrupted, some proviruses can reactivate, spurring HIV to replicate and start infecting other immune cells all over again.
"Our study results certainly show that finding a cure for HIV disease is going to be much harder than we had thought and hoped for," Siliciano said in a statement.
Researchers isolated 213 HIV proviruses from the reservoirs of 8 patients and found that 12% of those that initially seemed inactive could not only become active but were also capable of making copies of their genetic material and carrying the infection to other cells. These proviruses were once believe to be defective and therefore could not play a hand in rejuvenating the disease.
The study authors hope the discovery will encourage alternative approaches to developing drugs for HIV, which affects an estimated 1.18 million people in the U.S. and 34 million people worldwide.
- here's the Cell abstract
- read the press release