Brothers in arms
March 17, 2009Influenza, or flu, is an unpleasant affair with fever, cough, as well as head and body ache. When this illness is further complicated by a bacterial pneumonia, a harmful super-infection develops. Until now, researchers thought that the flu facilitates an infection with pneumonia bacteria because it leads to a decrease of immune cells in the blood and thus impairs the body's defenses.
A joint venture from researchers from the Helmholtz-Centre for Infection Research (HZI) in Braunschweig, the Otto-von-Guericke-University in Magdeburg, and the Karolinska institute in Sweden have taken an in-depth look at the connection between flu infection and pneumonia. Their results, recently released in the scientific journal "PLoS One", have disproven a common theory about flu-like pneumonia.
Some viral infections trigger a decrease of immune cells in the blood - a so-called "lymphopenia". The reasons behind it and whether this is the case with influenza are unknown. To investigate the latter, HZI researchers infected mice with flu viruses and measured the amount of immune cells in the animal's blood every day. Some days later, flu-infected mice received a dosage of pneumonia bacteria usually harmless for healthy mice. While the flu-infected mice did develop a superinfection & subsequently died, surprisingly, they were not suffering from lymphopenia. The healthy, non-flu-infected mice defeated the bacteria successfully and recovered.
To discover whether a lack of immune cells encourages an infection with pneumonia bacteria in general, an artificial drug-induced lymphopenia was established in the mice. Without infecting these lymphopenic mice with flu viruses, they received pneumonia bacteria. Despite a severe lack of immune cells, the mice recovered completely.
With these results, the researchers could show that influenza facilitates and intensifies an infection from pneumonia bacteria, while disproving the common idea that this is caused by a lack of immune cells. "This result was an enormous surprise for us because it directly contradicts widespread assumptions", says Sabine Stegemann, researcher in the groups "Immune regulation" at the HZI and "Molecular Immunology" at the Otto-von-Guericke-University in Magdeburg.
"Now we want to understand the reasons for the increased susceptibility", says Matthias Gunzer, head of the group in Magdeburg. "It could be interplay of weakened mucous membranes and scavenger cells that induce ideal conditions for pneumonia bacteria to create a deadly lung infection. Another reason may be a reaction of the host immune system: It disables hyperactive flu-fighting immune cells to inhibit destruction of healthy lung tissue. "The immune system keeps itself under control and that makes it easy for pneumonia bacteria to infect the lung", says Gunzer.
More information: Stegemann S, Dahlberg S, Kröger A, Gereke M, Bruder D, et al. 2009 Increased Susceptibility for Superinfection with Streptococcus pneumoniae during Influenza Virus Infection Is Not Caused by TLR7-Mediated Lymphopenia. PLoS ONE 4(3): e4840. doi:10.1371/journal.pone.0004840
Source: Helmholtz Association of German Research Centres
-
Flu deaths could be reduced thanks to cancer research
Nov 17, 2008 |
not rated yet |
0
-
Researchers discover primary sensor that detects stomach viruses
Jul 18, 2008 |
not rated yet |
0
-
Study finds more effective treatment for pneumonia following influenza
Jan 08, 2009 |
not rated yet |
0
-
Feed a cold, feed a fever: Research shows calorie cut makes it harder to fight flu
Nov 25, 2008 |
not rated yet |
0
-
Protein enhances lethality of influenza virus
Oct 10, 2007 |
not rated yet |
0
-
Engineers build first sub-10-nm carbon nanotube transistor
Feb 01, 2012 |
4.9 / 5 (31) |
30
-
Something old, something new: Evolution and the structural divergence of duplicate genes
Jan 31, 2012 |
4.6 / 5 (7) |
1
-
The hidden nanoworld of ice crystals: Revealing the dynamic behavior of quasi-liquid layers
Jan 30, 2012 |
5 / 5 (3) |
1
-
Stock market network reveals investor clustering
Jan 27, 2012 |
3.9 / 5 (23) |
8
-
Of microchemistry and molecules: Electronic microfluidic device synthesizes biocompatible probes
Jan 26, 2012 |
5 / 5 (1) |
0
-
Classical and Quantum Mechanics via Lie algebras
Apr 15, 2011
- More from Physics Forums - Independent Research
More news stories
Study finds that anti-diabetic medication can prevent the long-term effects of maternal obesity
In a study to be presented today at the Society for Maternal-Fetal Medicine's annual meeting, The Pregnancy Meeting, in Dallas, Texas, researchers will report findings that show that short therapy with the anti-diabetic medication ...
Feb 11, 2012 |
5 / 5 (1) |
1
FDA-approved drug rapidly clears amyloid from the brain, reverses Alzheimer's symptoms in mice
Neuroscientists at Case Western Reserve University School of Medicine have made a dramatic breakthrough in their efforts to find a cure for Alzheimer's disease. The researchers' findings, published in the journal Science, show t ...
Medicine & Health / Neuroscience
Feb 09, 2012 |
4.9 / 5 (53) |
21
|
Green tea found to reduce disability in the elderly
(Medical Xpress) -- A lot of research has been done over the past several years looking into the health benefits of green tea. As a result, scientists have found that regular consumption of the beverage leads ...
Teen school drop-outs three times as likely to be on benefits in later life
Teen school drop-outs are almost three times as likely to be on benefits in later life as their peers who complete their schooling, indicates research published online in the Journal of Epidemiology and Community Health.
Feb 06, 2012 |
not rated yet |
12
To perform with less effort, practice beyond perfection
Whether you are an athlete, a musician or a stroke patient learning to walk again, practice can make perfect, but more practice may make you more efficient, according to a surprising new University of Colorado Boulder study.
Medicine & Health / Neuroscience
Feb 09, 2012 |
4.4 / 5 (15) |
6
|
Google might launch Drive for cloud storage soon
(PhysOrg.com) -- Google's next big move, according to the Wall Street Journal, is a cloud storage service called Drive. Hardly first to the plate, Google is simply catching up to introducing its cloud reposi ...
Latin America mining boom clashes with conservation
Latin America is experiencing a mining boom as prices rise fuelled by a hike in global demand, but the region is also being hit by a wave of violent protests, strikes and rallies by environmentalists.
Walney offshore wind farm is world's biggest (for now)
(PhysOrg.com) -- The Walney wind farm on the Irish Sea--characterized by high tides, waves and windy weather--officially opened this week. The farm is treated in the press as a very big deal as the Walney ...
Love a click away in Indonesia's Twitter Republic
He was a geeky kid from Yogyakarta, she a glamorous city girl in Jakarta. In a country with one of the world's most vibrant social networking scenes they fell in love on Twitter.
Europeans protest controversial Internet pact
Tens of thousands of people marched in protests in more than a dozen European cities Saturday against a controversial anti-online piracy pact that critics say could curtail Internet freedom.
Navy to begin tests on electromagnetic railgun prototype launcher
The Office of Naval Research (ONR)'s Electromagnetic (EM) Railgun program will take an important step forward in the coming weeks when the first industry railgun prototype launcher is tested at a facility ...