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, email@example.com.
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!
Brought to light – chromobodies reveal changes in endogenous protein concentration in living cells
21.09.2018 | NMI Naturwissenschaftliches und Medizinisches Institut an der Universität Tübingen
A one-way street for salt
21.09.2018 | Julius-Maximilians-Universität Würzburg
The building blocks of matter in our universe were formed in the first 10 microseconds of its existence, according to the currently accepted scientific picture. After the Big Bang about 13.7 billion years ago, matter consisted mainly of quarks and gluons, two types of elementary particles whose interactions are governed by quantum chromodynamics (QCD), the theory of strong interaction. In the early universe, these particles moved (nearly) freely in a quark-gluon plasma.
This is a joint press release of University Muenster and Heidelberg as well as the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt.
Then, in a phase transition, they combined and formed hadrons, among them the building blocks of atomic nuclei, protons and neutrons. In the current issue of...
Thin-film solar cells made of crystalline silicon are inexpensive and achieve efficiencies of a good 14 percent. However, they could do even better if their shiny surfaces reflected less light. A team led by Prof. Christiane Becker from the Helmholtz-Zentrum Berlin (HZB) has now patented a sophisticated new solution to this problem.
"It is not enough simply to bring more light into the cell," says Christiane Becker. Such surface structures can even ultimately reduce the efficiency by...
A study in the journal Bulletin of Marine Science describes a new, blood-red species of octocoral found in Panama. The species in the genus Thesea was discovered in the threatened low-light reef environment on Hannibal Bank, 60 kilometers off mainland Pacific Panama, by researchers at the Smithsonian Tropical Research Institute in Panama (STRI) and the Centro de Investigación en Ciencias del Mar y Limnología (CIMAR) at the University of Costa Rica.
Scientists established the new species, Thesea dalioi, by comparing its physical traits, such as branch thickness and the bright red colony color, with the...
Scientists have succeeded in observing the first long-distance transfer of information in a magnetic group of materials known as antiferromagnets.
An international team of researchers has mapped Nemo's genome, providing the research community with an invaluable resource to decode the response of fish to...
21.09.2018 | Event News
03.09.2018 | Event News
27.08.2018 | Event News
24.09.2018 | Physics and Astronomy
24.09.2018 | Information Technology
21.09.2018 | Physics and Astronomy