Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Why some strains of Lyme disease bacteria are common and others are not

04.12.2012
Findings could lead to novel strategy to control disease

New clues about the bacteria that cause Lyme disease could lead to a novel strategy to reduce infections, according to a study to be published in mBio®, the online open-access journal of the American Society for Microbiology, on December 4.

The study reveals that the immune system of the white-footed mouse, a very common reservoir for Borrelia burgdorferi (the bacterium that causes the disease), responds differently to different strains of the bacterium, a finding that will help scientists tweak the animals' immune systems to prevent infection. A vaccine that keeps these wild mice free of the pathogen could significantly curb the spread of the disease from mice to ticks to humans.

"There's no human vaccine, and there's not likely to be one," says Alan Barbour of the University of California, Irvine, the lead author of the study. "We have to focus on lowering the risk. One way to do that is by treating the animals that carry the disease." Rabies offers a good example of how this might be accomplished, says Barbour. By deploying vaccine-laced food bait, public health officials have managed to lower the rabies infection rate in wildlife and significantly limited the spread of the disease to pets and humans.

Although Lyme disease only emerged in the U.S. in the past 40 years or so, around 25,000 cases are now reported every year in this country and the medical costs of these cases are estimated to range in the billions of dollars. Despite the growing importance of the disease, little is known about the evolution and ecology of the bacterium that causes the illness.

Barbour and his colleagues sought to understand why as many as 15 different strains of B. burgdorferi exist in the wild at differing degrees of prevalence. In the parts of the country where Lyme disease is most common, the majority of white-footed mice are infected with B. burgdorferi during the course of the year. Unlike humans and lab mice, white-footed mice don't get sick when they're infected so the bacteria grow and multiply within them, and when a deer tick bites it sucks up the bacteria along with its blood meal.

In the lab, the group at UC Irvine exposed white-footed mice to various strains of B. burgdorferi and tracked the course of the infection. All the B. burgdorferi strains infected the white-footed mice, but some strains managed to grow to high densities in various mouse tissues while others did not.

Barbour says the immune reactions the mice mounted against the various strains explain these discrepancies: the greater the immune response, the fewer bacteria found in a mouse's tissues and vice-versa. Importantly, the strains that grew to greatest densities within the mice are also the strains that are most prevalent in the wild.

When they looked at the immune reaction to individual B. burgdorferi proteins the authors found a complex interplay of reactivities. The mice reacted in different degrees to the various proteins present in a single bacterial strain, which could explain why such a great diversity of B. burgdorferi strains are sustained in the wild, say the authors.

Barbour says knowing more about how the white-footed mouse reacts to all the various B. burgdorferi strains and immunogenic proteins will help vaccine developers select the best proteins to put in a vaccine. "The best candidate for the mouse vaccine is something that's the same in all the [B. burgdorferi] strains," he says.

Once a vaccine for the white-footed mouse is developed, it will need to be tested by exposing immunized mice to a selected set of diverse B. burgdorferi strains, says Barbour, and the results of this study can help make that selection. "If we can find five that are representative, that would be an advantage."

This study, he says, "is going to provide a foundation for future studies in understanding the infection in these animals as we proceed with developing vaccines."

mBio® is an open access online journal published by the American Society for Microbiology to make microbiology research broadly accessible. The focus of the journal is on rapid publication of cutting-edge research spanning the entire spectrum of microbiology and related fields. It can be found online at http://mBio.asm.org.

The American Society for Microbiology is the largest single life science society, composed of over 39,000 scientists and health professionals. ASM's mission is to advance the microbiological sciences as a vehicle for understanding life processes and to apply and communicate this knowledge for the improvement of health and environmental and economic well-being worldwide.

Jim Sliwa | EurekAlert!
Further information:
http://www.asmusa.org

More articles from Life Sciences:

nachricht Study shines light on brain cells that coordinate movement
26.06.2017 | University of Washington Health Sciences/UW Medicine

nachricht New insight into a central biological dogma on ion transport
26.06.2017 | Aarhus University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Study shines light on brain cells that coordinate movement

26.06.2017 | Life Sciences

Smooth propagation of spin waves using gold

26.06.2017 | Physics and Astronomy

Switchable DNA mini-machines store information

26.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>