What: Scientists studying the Anopheles gambiae mosquito – the main vector of malaria – have found that when the mosquito takes a blood meal, that act triggers two enzymes to form a network of crisscrossing proteins around the ingested blood.
The formation of this protein barrier, the researchers found, is part of the normal digestive process that allows so-called "healthy" or commensal gut bacteria to grow without activating mosquito immune responses.
But there is a downside: The barrier also prevents the mosquito's immune defense system from clearing any disease-causing agents that may have slipped into the blood meal, such as the Plasmodium malaria parasite, which in turn can be passed on to humans.
Disrupting the protein barrier, however, can trigger mosquito immune defenses to intervene and protect the insect from infection, notes the research team from the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health. The enzymes involved in the protein barrier are called immunomodulatory peroxidase (IMPer) and dual oxidase (Duox).
The researchers believe it might be possible to prevent the formation of the protein barrier by immunizing people with IMPer or the proteins that crisscross. This vaccine would generate antibodies that, after a mosquito feeds on a human, could disrupt the barrier, reduce parasite survival in the mosquito and prevent malaria transmission.
The role of IMPer-Duox in forming a protective barrier was unexpected – and previously unrecognized, according to Carolina Barillas-Mury, M.D., Ph.D., the senior study author. When her research group silenced, or turned off, the gene for either IMPer or Duox, the mosquito's midgut immune system took over and greatly reduced Plasmodium infection, indicating that IMPer and Duox are both required for parasite survival.
The IMPer-Duox system also is found in the mucous membrane of some human tissues, such as the colon. Dr. Barillas-Mury's group is investigating whether a protective protein barrier similar to that seen in mosquitoes also forms in vertebrates, including humans. If so, the barrier could be part of the process that normally prevents the colon from activating immune responses against commensal bacteria, as this would be harmful and lead to chronic inflammation. The existence of such a barrier in humans could have broad implications for the prevention and treatment of diseases such as chronic inflammatory bowel disease.
Article: S Kumar et al. A peroxidase/dual oxidase system modulates midgut epithelial immunity in Anopheles gambiae. Science. DOI 10.1126/science.1184008 (2010).
Who: Carolina Barillas-Mury, M.D., Ph.D., chief of the Mosquito Immunity and Vector Competence Unit in NIAID's Laboratory of Malaria and Vector Research, is available to comment on this article.
Contact: To schedule interviews, please contact the NIAID Communications Office, 301-402-1663, firstname.lastname@example.org.
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.
NIAID Communications Office | EurekAlert!
Single-stranded DNA and RNA origami go live
15.12.2017 | Wyss Institute for Biologically Inspired Engineering at Harvard
New antbird species discovered in Peru by LSU ornithologists
15.12.2017 | Louisiana State University
DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.
Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...
MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.
Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...
Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...
Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.
To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...
The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.
Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...
11.12.2017 | Event News
08.12.2017 | Event News
07.12.2017 | Event News
15.12.2017 | Power and Electrical Engineering
15.12.2017 | Materials Sciences
15.12.2017 | Life Sciences