Scientists find where HIV 'hides' to evade detection by the immune system

In a decades-long game of hide and seek, scientists from Sydney's Westmead Institute for Medical Research have confirmed for the very first time the specific immune memory T-cells where infectious HIV 'hides' in the human body to evade detection by the immune system. The team, led by Associate Professor Sarah Palmer from the University of Sydney, developed a pioneering full-length genetic sequencing assay for HIV. Using this test, the team found that genetically-intact HIV hides in specific subsets of CD4+ T-cells.

Associate Professor Palmer said that this next-generation test showed that HIV hides in the body's immune memory T-cells, which is how it avoids detection from the immune system.

"Previously it was thought that HIV was hiding primarily in central memory T-cells, but our new HIV genetic sequencing test has revealed that the majority of replication-competent virus is actually hiding in effector memory T-cells.

"HIV is really very clever. Essentially, it is hiding in the exact same cells within the immune system that are meant to attack it," she said.

Effector memory T-cells are the cells in the body that 'remember' previous infections and how to defeat them. These are the cells that provide life-long immunity to infections such as measles or chicken pox.

Associate Professor Palmer explained that only a very small proportion - approximately five per cent - of HIV is genetically intact. However, it is this small proportion of virus that hides in the effector memory T-cells and stops the immune system from fully destroying the virus and eliminating it from the body.

"When HIV replicates it makes a lot of errors and releases a lot of defective virus.

"But this five per cent of genetically intact HIV is the key. This virus inserts its genome into the body's memory cells and sits there quietly avoiding detection by the immune system," Associate Professor Palmer explained.

"These infected cells go into a resting state and stop producing HIV, but these latent cells can wake up and start making infectious HIV.

"It is a ticking time bomb waiting to re-infect a patient.

"The other 95 per cent of defective virus does send the immune system into overdrive. We suspect that this 'junk' HIV can act as a decoy and draw attention away from the "real" virus hiding in the effector memory T-cells," she said.

Despite groundbreaking advances in the treatment of HIV, it remains a chronic illness across the globe. Neither a cure nor a vaccine has been achieved.

"Current HIV drugs stop the virus from replicating, but there is still no way for us to 'cure' an individual with HIV. Patients need drugs or chemotherapy for the rest of their lives.

"This is a particular problem in the developing world where only 50 per cent of people have access to regular HIV therapies.

"If a person suddenly stops taking their HIV treatments, the virus hidden in effector memory T-cells would spring to life and start producing more HIV, and the virus will spread throughout the body within two weeks.

"Now that we've identified where the replication-competent virus is hiding, we can start work towards targeting these cells with new therapies aimed at fully eliminating HIV from the body," Associate Professor Palmer concluded.

Hiener B, Horsburgh BA, Eden JS, Barton K, Schlub TE, Lee E, von Stockenstrom S, Odevall L, Milush JM, Liegler T, Sinclair E, Hoh R, Boritz EA, Douek D, Fromentin R, Chomont N, Deeks SG, Hecht FM, Palmer S.
Identification of Genetically Intact HIV-1 Proviruses in Specific CD4+ T Cells from Effectively Treated Participants.
Cell Rep. 2017 Oct 17;21(3):813-822. doi: 10.1016/j.celrep.2017.09.081.

Most Popular Now

Fasenra (benralizumab) receives US FDA approval fo…

AstraZeneca and its global biologics research and development arm, MedImmune, announced that the US Food and Drug Administration (FDA) has approved Fasenra (benralizumab)...

Alzheimer's disease might be a 'whole body' proble…

Alzheimer's disease, the leading cause of dementia, has long been assumed to originate in the brain. But research from the University of British Columbia and Chinese scie...

Cancer cells destroyed with dinosaur extinction me…

Cancer cells can be targeted and destroyed with the metal from the asteroid that caused the extinction of the dinosaurs, according to new research by an international col...

Novartis confirms leadership in multiple sclerosis…

Novartis today announced it will present 54 scientific abstracts from across its multiple sclerosis (MS) research portfolio at the 7th Joint European and Americas Committ...

Pfizer receives FDA approval for SUTENT® (sunitini…

Pfizer Inc. (NYSE:PFE) today announced that the U.S. Food and Drug Administration has approved a new indication expanding the use of SUTENT® (sunitinib malate) to include...

Amgen and Novartis announce expanded collaboration…

Amgen (NASDAQ:AMGN) and Novartis announced an expanded collaboration with the Banner Alzheimer's Institute (BAI) to initiate a new trial - the Alzheimer's Prevention Init...

Transplanted hematopoietic stem cells reverse dama…

Researchers at University of California San Diego School of Medicine report that a single infusion of wildtype hematopoietic stem and progenitor cells (HSPCs) into a mous...

Novartis announces the planned acquisition of Adva…

Novartis announced today, that it has entered a memorandum of understanding with Advanced Accelerator Applications (AAA) under which Novartis intends to commence a tender...

'Precision Medicine' may not always be so precise

Precision Medicine in oncology, where genetic testing is used to determine the best drugs to treat cancer patients, is not always so precise when applied to some of the w...

New tissue-engineered blood vessel replacements on…

Researchers at the University of Minnesota have created a new lab-grown blood vessel replacement that is composed completely of biological materials, but surprisingly doe...

New US study reveals key reasons why millions of p…

Few of the more than 90 million Americans(1) with obesity are seeking and receiving long-term obesity care, according to new data from the Awareness, Care and Treatment I...

China's out of control 'silent killer' affects one…

More than one-third of adults in China have high blood pressure - often dubbed the "silent killer" for its lack of symptoms - but only about one in 20 have the condition ...

Pharmaceutical Companies

[ A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Z ]