27th Apr 2018
27th Apr 2018
Curated by Endre Szvetnik
Although antiretroviral drugs effectively suppress HIV in patients, the virus still hides within their cells. Scientists are trying out new molecules that can make it a visible target for the immune system.
In 10 seconds? ‘Latency-reversing agents’ are promising compounds in the battle against HIV. Scientists have managed to use them to tackle ‘latency’, one of the key tricks that HIV uses to hide from immune cells trying to clear the virus from the body. (Read the science)
So what exactly is latency? It’s the ability of the virus to stop replicating and lie dormant in a subset of immune cells called CD4+ T. In HIV-infected people who are on antiretroviral therapy (ART), the virus is suppressed to very low levels, but it still lurks around unseen by the immune system. (More on HIV-latency)
And what’s the news on this front? Scientists have managed to reactivate HIV in its usual hiding place – cells known as the viral reservoir – using chemicals called ‘latency reversal agents’, or LRAs. This is important because the active virus becomes a visible target for killer immune cells, so it can be destroyed. Researchers call this the ‘kick and kill’ method. (Read more on LRAs)
How did they do it? In a recent study of 20 HIV patients on ART, researchers found that a drug called maraviroc led to an increase in HIV transcription in resting CD4+ T cells. Transcription is part of how the virus replicates – and this activity gives away the HIV’s hiding place. This supports the idea that LRAs could be used to eliminate virus reservoirs in HIV patients. (Read more)
And is this already effective? It still needs fine-tuning. Sole ‘agents’ are less effective, but researchers using computational models discovered that pairs of LRAs can significantly reverse HIV latency, so this is a promising path for further research. (Read more)
Is anything else being tried? Absolutely – scientists are looking into how our genes can affect HIV latency. One previously unrecognised ‘instruction’ regulating genes is called histone crotonylation. Researchers used an enzyme boosting crotonylation in HIV-infected lab monkeys and managed to reactivate the latent virus in their gut cells. The next step is to repeat this in humans, which can lead to new drugs and possibly, a cure. (Read more)
Researchers experiment with traditional medicine to fight latency
Scientists have studied plant extracts from traditional medications to see if their compounds could help reverse HIV latency.
They used a plant called Croton megalobotrys, which has been long known for its medicinal properties in South-East Asia, Africa and South America.
The extracts appeared to reverse latency in lab conditions, and when added to the diets of a small number of HIV patients, they reported improved health – but of course, further research is needed!
(Find the paper on Sparrho)
(Psst, Endre distilled 9 research papers to save you 633.3 min)