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
JAN 19, 2020
Health & Medicine
JAN 19, 2020
Siblings lead Researchers to Discover New Immunodeficiency Disease
An infant was suffering from inflammatory bowel disease, eczema, food allergies, lung disease, and persistent cytomegalovirus (CMV) infection. His older si...
JAN 19, 2020
Microbiology
JAN 19, 2020
Dengue Vaccine Reaches the Clinic, with Restrictions
Dengue fever is an unusual virus that presented complications for the recently-developed and first vaccine for the disease....
JAN 19, 2020
Health & Medicine
JAN 19, 2020
Blood-Brain Barrier Impairment and Its Role in Alzheimer's Disease
In healthy people, the blood-brain barrier (BBB), which is fromed by brain endothelial cells, strictly controls the entrance of harmful materials into...
JAN 19, 2020
Health & Medicine
JAN 19, 2020
Diagnosis and Treatment of Neurosarcoidosis
Sarcoidosis is a multisystem inflammatory disease characterized by the formation of non-caseating granulomas in the affected organs. The majority of p...
JAN 19, 2020
Immunology
JAN 19, 2020
Researchers Identify Pair of "Recruiters" that Pull T Cells to the Lungs
How do CD8 T cells make it to the lungs to help in the fight against infection? Why don’t T cells remain longer in the lungs? How can science optimiz...
JAN 19, 2020
Microbiology
JAN 19, 2020
Ketogenic Diet Appears to Help Protect Against the Flu
The ketogenic diet forces the body to use stored fat as fuel instead of carbohydrates; the fat gets broken down into ketone bodies....
Loading Comments...