JUL 09, 2015 12:14 PM PDT

Do Biofilms Spur Autoimmunity?

WRITTEN BY: Kerry Evans
Biofilms consist of surface-associated bacteria surrounded by an extracellular matrix (think dental plaque). Biofilms often form on urinary catheters and orthopedic implants, where the bacteria may infect bone or enter the blood stream. However, researchers at Temple University Health System have now implicated gut biofilms in the development of systemic lupus erythematosus, an autoimmune disease. Cagla Tukel, PhD, and Stefania Galluci, MD, report their findings in the journal Immunity.

Bacteria secrete polysaccharides, DNA, and other substances to form a biofilm.
Lupus is a systemic inflammatory disease, and flare-ups can cause joint pain and swelling, skin lesions, fatigue, fever, and the characteristic "butterfly" facial rash. Tukel and Galluci knew that lupus flares also coincided with bacterial infections, particularly Salmonella, and questioned whether gut-resident biofilms play a role. The group showed that Escherichia coli and Salmonella typhimurium, common gut bacteria, form biofilms containing extracellular DNA and amyloid fibers (curli).

When they exposed dendritic cells to E. coli or Salmonella DNA/curli complexes, they produced pro-inflammatory cytokines, such as type-1 interferon. Then, when lupus-prone mice were injected with the DNA/curli complexes, they produced auto-antibodies typical of lupus within two weeks. Such a response to other bacterial products, like lipopolysaccharide, generally takes up to five months.

Tukel and Galluci are now collaborating with Roberto Carrichio, MD, Director of the Temple Lupus Clinic, to probe for DNA/curli complexes in lupus patients. They also plan to develop a mouse model to understand just how the DNA/curli complexes move to the bloodstream from biofilms in the gut.

Sources: Science Daily, Mayo Clinic, Amyloid-DNA Composites of Bacterial Biofilms Stimulate Autoimmunity. Immunity, 2015; 42 (6): 1171

About the Author
  • Kerry received a doctorate in microbiology from the University of Arkansas for Medical Sciences.
You May Also Like
MAR 23, 2021
Genetics & Genomics
Implementing Illumina NGS is a lot easier than you think.
MAR 23, 2021
Implementing Illumina NGS is a lot easier than you think.
Dr. John-Sebastian Eden is a Virologist at the Westmead Institute for Medical Research in Sydney, Australia. His group u ...
MAR 18, 2021
Microbiology
How a Chronic Hepatitis B Infection Happens
MAR 18, 2021
How a Chronic Hepatitis B Infection Happens
Hepatitis B can cause a long-term and sometimes fatal disease. Princeton University researchers have learned more about ...
MAY 13, 2021
Microbiology
The Gut Microbiome Was More Diverse in Ancient People
MAY 13, 2021
The Gut Microbiome Was More Diverse in Ancient People
What can we learn from a specimen of ancient poo? A lot, it turns out. Scientists have now reported their findings from ...
MAY 27, 2021
Clinical & Molecular DX
Breakthrough Diagnostic Detects TB Infections in Infants Sooner
MAY 27, 2021
Breakthrough Diagnostic Detects TB Infections in Infants Sooner
There are nearly a million cases of tuberculosis (TB) every year, and over 80 percent of childhood deaths from TB occur ...
MAY 30, 2021
Microbiology
The Mechanics of a Gliding Microbe, Revealed
MAY 30, 2021
The Mechanics of a Gliding Microbe, Revealed
Humans have been able to use machines to master movement, but there are many organisms that can get around just fine on ...
JUN 03, 2021
Microbiology
How HIV Can Deplete White Matter in the Brain
JUN 03, 2021
How HIV Can Deplete White Matter in the Brain
The brain is sometimes called grey matter, which is made up of neurons. But it also contains white matter, which are neu ...
Loading Comments...