SEP 30, 2015 1:58 PM PDT

Newly Discovered Membrane Protein Could Help Immune System Fight HIV

WRITTEN BY: Kara Marker
Currently in the United States, 13 percent of the 1.2 million people infected with HIV are unaware of their condition ( HIV treatment is costly, and if the virus isn't contained, the infection will transition into the acquired immunodeficiency syndrome, commonly known as AIDS (CDC). HIV has been intensely studied in the past few decades and has become a highly researched virus. Still, there are parts of its virulence that scientists still don't understand. Today, scientists from the University of Geneva and University of Trento peeled away an important layer of the HIV mystery by discovering a new membrane protein. 
An HIV viral particle
HIV has an accessory protein called Nef that is necessary for viral replication and development inside host cells. Since Nef's role is known to be vital to HIV virulence, multiple studies have surrounded inactivating, blocking, or otherwise stopping its action. Nef alters the attack of T lymphocytes, macrophages, and other key immune cells so the immune system can not adequately protect the body. In addition, Nef increases the infectivity of HIV viral particles. Geneva and Trento scientists realized that the action of Nef may explain why some human cells are more vulnerable to infection than others. 

In their experiment, the researchers used an HIV strain with the Nef protein knocked out so they could visualize which host cells are targeted the most by HIV. The results showed that the cells least sensitive to the NEF knockout strain were cells containing a membrane protein, named SERINC5. Dr. Massimo Pizzato from the University of Trento and also the organizer of the study, explained the action of SERINC5 as a protein that warns other cells as HIV attempts to spread and replicate in different host cells. When the virus breaks free of one cell to infect and replicate in other cells, it takes SERINC5 membrane protein along with it. When attempting to infect a new cell, the presence of SERINC5 provides enough warning so "the virus is therefore no longer able to penetrate." 

Putting two and two together, the team was able to determine that Nef inhibits SERINC5, allowing HIV  to travel from cell to cell, infecting the host without raising any alarm. This conclusion comes from seeing in the experiment with the Nef knockouts that the cells with SERINC5 were not nearly as easily influenced by the mutant viral strain. Without Nef, SERINC5 worked like it is supposed to, warning the other cells of the oncoming infection. 

This discovery of the connection between HIV accessory protein Nef and human membrane protein SERINC5 could be vital in taking the next step toward treating an HIV infection before it progresses to AIDS. The scientists involved in this study found that pushing expression of SERINC5 to levels that Nef cannot contain could be a new HIV treatment. 

Frederico Santoni, co-author of the study and a scientist at Geneva, explains the significance of the results like this: "Moreover, contrary to the antiretroviral factors previously discovered, which are activated by interferon,  SERINC5 is expressed continuously in all cells of our immune system."

The team looks ahead to the potential of turning the defensive mechanism of SERINC5 into new therapeutic options for the millions of patients with HIV infections.

Check out the following video from the Howard Hughes Medical Institute to learn more in detail about the replication and life cycle of HIV. 

Sources: EurekAlert and University of Geneva

About the Author
  • I am a scientific journalist and enthusiast, especially in the realm of biomedicine. I am passionate about conveying the truth in scientific phenomena and subsequently improving health and public awareness. Sometimes scientific research needs a translator to effectively communicate the scientific jargon present in significant findings. I plan to be that translating communicator, and I hope to decrease the spread of misrepresented scientific phenomena! Check out my science blog:
You May Also Like
OCT 02, 2019
OCT 02, 2019
Surface Plasmon Resonance (SPR) Technology
Surface plasmon resonance (SPR) allows researchers to investigate different types of biomolecular interactions and mechanisms in real-time and label-free....
DEC 16, 2019
Drug Discovery & Development
DEC 16, 2019
Drug Targets Against The Nipah Virus
The Nipah virus, first identified in 1998 and is transmitted from pigs and bats, has resulted in a high mortality rate killing more than half of all infect...
DEC 31, 2019
Genetics & Genomics
DEC 31, 2019
Should the Scientist Behind World's First Gene Edited Babies be in Prison?
He Jiankui, the scientist behind the world’s first gene-edited babies in 2018, has been sentenced to three years in prison by Chinese authorities for...
JAN 19, 2020
JAN 19, 2020
Overactive Immune Gene May Cause Schizophrenia
A windy road links excessive activity of the “C4” gene to the development of schizophrenia. Researchers begin to study C4 activity as part of n...
JAN 22, 2020
JAN 22, 2020
How the VISTA molecule affects immune responses
A new study describes how a molecule named VISTA has been impeding immune responses in cancer therapies. By turning this molecule “off,” resear...
FEB 21, 2020
Drug Discovery & Development
FEB 21, 2020
New Antibiotics Found Using AI Technology
Using AI, researchers at MIT have found a powerful new antibiotic capable of killing some of the most dangerous drug-resistant bacteria known to man. ...
Loading Comments...