FEB 19, 2016 08:11 AM PST

Bacterial Hitchhikers Are Invading

WRITTEN BY: Kara Marker
Bacteria are a little more clever in the way they enter the body and stay undetected than scientists realized. From the University of North Carolina (UNC) School of Medicine, scientists have identified bacterial “hitchhikers," bacteria that find lodging in the body’s own immune cells.

Francisella tularensis is the agent causing a disease called tularemia. All patients with tularemia show signs of fever, but depending where the bacteria entered the body, secondary symptoms can vary. Some symptoms are sore throat, skin ulcers, mouth ulcers, and difficulty breathing (CDC). Tularemia can be treated with antibiotics, but the new discovery from UNC has scientists thinking there could be another way, one without the potential for bacteria to grow back resistant and stronger than ever.

According to the team from UNC, F. tularensis has “remarkable virulence,” meaning that it takes very few bacteria to cause an extensive infectiom in a human host. In their study, recently published in the journal eLife, UNC researchers discovered that F. tularensis has another secret weapon: the ability to hijack macrophages and survive inside of them.
 
Francisella tularensis


Macrophages are vital cells of the immune system during a bacterial invasion. They “eat” pathogens and apoptotic cells, and they activate immune effector molecules as backup (Nature). In addition to finding refuge in macrophages, the very cells the body recruits to destroy pathogens like bacteria, F. tularensis interferes with macrophages’ own apoptotic function. Apoptosis is a mechanism cells depend on to self-destruct when they have been compromised. By preventing macrophages from destroying themselves, F. tularensis has more time to spread to other cells, exacerbating the infection.

And how do they spread to other cells? Again, F. tularensis takes advantage of regular macrophage function to serve its own purpose. A process called “trogocytosis” describes an exchange between cells where they “bump against each other, exchange a few surface proteins, and separate.” In their study, UNC scientists discovered that F. tularensis bacteria prompt macrophages to participate in trogocytosis more often, jumping from cell to cell while they do so.

The scientists from the UNC study are hoping that by temporarily inhibiting trogocytosis, bacterial infections that take advantage of macrophages in this way can be thwarted in a more long-lasting manner, since bacteria most likely will not be able to develop resistance. 
 

Source: UNC Health
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: ScienceKara.com.
You May Also Like
MAY 04, 2018
Clinical & Molecular DX
MAY 04, 2018
New Blood Test Detects Peanut Allergy with 98% Specificity
A new blood test trumps traditional diagnostic methods for determining peanut allergy, the most common allergy for children. From the Medical Research Coun...
MAY 16, 2018
Immunology
MAY 16, 2018
Antibodies Neutralize Two Different Hemorrhagic Fever Viruses
Scientists have found evidence for potential antibody-based therapeutics to treat more than one hemorrhagic fever virus at once. From Harvard Medical Schoo...
JUN 14, 2018
Health & Medicine
JUN 14, 2018
Beware of Hotel Room Germs
Recently the CDC came out with a study that showed nearly 1/3 of swimming-related illnesses from 2000-2014 could be traced back to pathogens found in hotel...
JUN 22, 2018
Health & Medicine
JUN 22, 2018
A New Test for Peanut Allergy: Better, Faster, Cheaper.
Scientists from the Medical Research Council (MRC) in the UK have come up with a test to detect peanut allergies and it’s safer, quicker and more acc...
SEP 10, 2018
Immunology
SEP 10, 2018
The Immune System: A New Hope for Opioid Addiction?
Addiction, Immunology, Opioid...
SEP 14, 2018
Immunology
SEP 14, 2018
Zika Strong Arms the Immune System
Zika Virus manipulates the genetic makeup of immune cells called macrophages....
Loading Comments...