A team of scientists from government, academia and private industry has developed a novel treatment that protects mice from infection with the bacterium that causes tularemia, a highly infectious disease of rodents, sometimes transmitted to people, and also known as rabbit fever.
In additional experiments with human immune cells, the treatment also demonstrated protection against three other types of disease-causing bacteria that, like the tularemia bacteria, occur naturally, can be highly virulent, and are considered possible agents of bioterrorism.
The experimental therapeutic works by stimulating the host immune system to destroy invading microbes. In contrast, antibiotics work by directly attacking invading bacteria, which often develop resistance to these medications. The therapeutic has the potential to enhance the action of antibiotics and provide an alternative to them.
"A therapeutic that protects against a wide array of bacterial pathogens would have enormous medical and public health implications for naturally occurring infections and potential agents of bioterrorism," says Anthony S. Fauci, M.D., director of the National Institute of Allergy and Infectious Diseases (NIAID) at the National Institutes of Health. "This creative approach is a prime example of public-private partnerships that can facilitate progress from a basic research finding to new, desperately needed novel therapeutics."
Catharine Bosio, Ph.D., and her colleagues at NIAID's Rocky Mountain Laboratories in Hamilton, Mont., led the study. Study collaborators are from Colorado State University in Fort Collins and Juvaris Biotherapeutics of Burlingame, Calif. The study is available online in the open-access journal PLoS Pathogens.
In the study, the researchers combined components isolated from the membrane of a weakened strain of Francisella tularensis, the agent of tularemia, with the Juvaris product CLDC (cationic liposome DNA complexes). The combination stimulated a natural antibacterial mechanism, called reactive oxygen species (ROS) and reactive nitrogen species (RNS), in immune cells that ingest bacteria. ROS and RNS attack and kill invading bacteria, preventing replication and spread of the pathogens to other cells.
Sixty percent of mice in the study survived lethal pulmonary infection with virulent F. tularensis when treated with the therapeutic intravenously three days before the bacterial challenge. No mice survived when given the bacterial components or the CLDC alone, demonstrating the importance of combining both to maximize protection in mouse and human cells. The treatment also showed broad usage, protecting human immune cells from bacteria that cause plague, melioidosis and brucellosis as well as tularemia. Melioidosis is primarily a tropical disease spread to humans and animals through contaminated soil and water. Brucellosis is a disease that primarily affects animals, including humans who come in contact with infected animals or animal products, such as contaminated milk.
According to Dr. Bosio, the three-day advance treatment appears crucial to providing enough time to stimulate the immune system. Any treatment less than three days in advance failed to protect the mice, she said.
"We are continuing to improve the versatility of this treatment as an antibacterial therapeutic with respect to timing of delivery and efficacy," she says. "Meanwhile, CLDC plus membrane protein fractions is proving to be an excellent tool to determine how to safely and successfully stimulate the body's own antibacterial army to protect itself against highly infectious invaders."
The research team will continue to study the precise role that membrane protein fractions play in combination with CLDC, and how the combination affects the production of RNS and ROS in cells from mice and from humans.
For more information, visit NIAID' Tularemia Web page at http://www.niaid.nih.gov/topics/tularemia/Pages/research.aspx.
NIAID conducts and supports research—at NIH, throughout the United States, and worldwide—to study the causes of infectious and immune-mediated diseases, and to develop better means of preventing, diagnosing and treating these illnesses. News releases, fact sheets and other NIAID-related materials are available on the NIAID Web site at http://www.niaid.nih.gov.
The National Institutes of Health (NIH)—The Nation's Medical Research Agency—includes 27 Institutes and Centers and is a component of the U. S. Department of Health and Human Services. It is the primary federal agency for conducting and supporting basic, clinical and translational medical research, and it investigates the causes, treatments and cures for both common and rare diseases. For more information about NIH and its programs, visit http://www.nih.gov.
Reference: R Ireland et al. Effective, broad spectrum control of virulent bacterial infections using cationic DNA liposome complexes combined with bacterial antigens. PLoS Pathogens 6(5): e1000921. DOI:10.1371/journal.ppat.1000921 (2010).
Ken Pekoc | EurekAlert!
Penn studies find promise for innovations in liquid biopsies
30.03.2017 | University of Pennsylvania School of Medicine
'On-off switch' brings researchers a step closer to potential HIV vaccine
30.03.2017 | University of Nebraska-Lincoln
The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.
To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
30.03.2017 | Health and Medicine
30.03.2017 | Health and Medicine
30.03.2017 | Medical Engineering