How the Human Immunodeficiency Virus can Infect Macrophages

by Dr. Trupti Shirole on  January 27, 2017 at 6:25 AM AIDS/HIV News
RSS Email Print This Page Comment bookmark
Font : A-A+

Macrophages are a type of white blood cell integral to the immune system. They make an antiviral protein called SAMHD1, which prevents human immunodeficiency virus (HIV) from replicating in these cells.
 How the Human Immunodeficiency Virus can Infect Macrophages
How the Human Immunodeficiency Virus can Infect Macrophages

A team led by UCL researchers has identified how HIV is able to infect macrophages despite the presence of a protective protein. They discovered a treatment that can maintain macrophage defenses which could be a key part of the puzzle of reaching a complete cure for HIV/AIDS.

Macrophages prevents HIV from replicating except for when the protein SAMHD1 is switched off, as part of a natural process discovered by the UCL-led team.

"We knew that SAMHD1 is switched off when cells multiply, but macrophages do not multiply so it seemed unlikely that SAMHD1 would be switched off in these cells," said Professor Ravindra Gupta (UCL Infection & Immunity), the senior author of the paper. "And yet we found there's a window of opportunity when SAMHD1 is disabled as part of a regularly-occurring process in macrophages."

Lead author of the EMBO Journal study, Dr Petra Mlcochova (UCL Infection & Immunity) said: "Other viruses can disable SAMHD1, but HIV cannot. Our work explains how HIV can still infect macrophages, which are disabling SAMHD1 by themselves."

The reason why SAMHD1 gets switched off remains to be determined, but the authors suggest it might be done in order to repair damaged DNA, part of the normal functioning of the macrophage.

In a further part of the study, the researchers discovered how to close this window of opportunity by treating the cells with HDAC inhibitors, which are sometimes used in cancer treatments.

"Our findings could help explain why some people undergoing anti-retroviral therapy for HIV continue to have HIV replication in the brain, as the infected cells in the brain are typically macrophages. While this is a barrier to achieving control of HIV in just a minority of patients, it may more importantly be a barrier to a cure," Gupta added.

The researchers say that macrophages can be an important reservoir of HIV infection that lingers away from the reach of existing treatments. Once a macrophage is infected, it will continually produce the HIV virus, so cutting off that point of infection within the body could be an important step towards safeguarding the entire immune system.

HDAC inhibitors may be particularly helpful as they're already known to reactivate latent HIV cells, thus making the virus vulnerable to the body's defences, especially if supported by anti-retroviral therapy.

The series of tests involved cultures of macrophages derived from human cells in vitro, which responded well to HDAC inhibitor treatment, as well as macrophages residing in mouse brain tissues.

Source: Eurekalert

Post a Comment

Comments should be on the topic and should not be abusive. The editorial team reserves the right to review and moderate the comments posted on the site.
Notify me when reply is posted
I agree to the terms and conditions

Related Links

More News on:

Oral Health And AIDS Chicken Pox AIDS/HIV AIDS/HIV - Epidemiology AIDS/HIV - Clinical Features AIDS/HIV - Health Education AIDS/HIV - Prevention And Transmission AIDS / HIV - Treatment AIDS/HIV- Lab Tests and Faqs Shigellosis 

News A - Z

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

News Search

Medindia Newsletters

Subscribe to our Free Newsletters!

Terms & Conditions and Privacy Policy.

Find a Doctor

Stay Connected

  • Available on the Android Market
  • Available on the App Store

News Category

News Archive

Loading...