Bacteria find safe-haven inside worms in return for helping them reproduce.
Inflammation clouds the transparent cornea, leading to cataract-like blindness.
Microbes, not the worms that carry them, aggravate the immune system.
Stowaway bacteria inside parasitic worms, and not the worms themselves, cause river blindness, according to new research. The finding could lead to better ways of preventing or treating the debilitating disease.
River blindness, or onchocerciasis, affects some 17 million people throughout central Africa and in parts of Arabia and South America. Sufferers develop inflammatory conditions. When inflammation occurs in the eyes it clouds the transparent cornea, leading to cataract-like blindness.
Bacterium-free worm extract doesn’t cause severe disease in the mice; Wolbachia-laden worms do. What’s more, Pearlman’s group found a molecular receptor in the eye that is particularly sensitive to Wolbachia. This receptor is crucial to eliciting an inflammatory immune response.
"It’s a very significant finding - it gives us a more precise idea of what’s happening," says Alexander Trees of the Liverpool School of Tropical Medicine in England. Trees’ group recently showed that filarial nematodes need Wolbachia bacteria to reproduce; antibiotics to kill Wolbachia can sterilize adult worms2.
"The more we know about this disease the better," agrees Juliet Fuhrman, who studies river blindness at Tufts University in Medford, Massachusetts. Wolbachia’s interaction with the immune system might provide a target for vaccines or other drugs to quell the disease itself, rather than the worms, Fuhrman hopes. "These may be our best chance," she says.
That Wolbachia are found in filarial nematodes is not so surprising. These bacteria live within numerous insects, where they specialize in manipulating their host’s reproduction. Researchers are keen to control them as they are essential to many harmful insects, including mosquitoes and crop pests3.
River blindness is currently managed with chemicals to stop adult filarial nematodes from reproducing and with insecticides to kill the black flies that carry the worms. These have curbed the disease quite successfully, but "the job isn’t done yet", warns Pearlman,
Antibiotics could be a good alternative, if Wolbachia is the culprit. Trials have begun, but widespread antibiotic use is difficult to enforce and runs the risk of the bacteria subsequently adapting to the drugs. "We’re all living in terror of resistance developing," says Fuhrman.
TOM CLARKE | © Nature News Service
How prenatal maternal infections may affect genetic factors in Autism spectrum disorder
22.03.2017 | University of California - San Diego
22.03.2017 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt
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...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
22.03.2017 | Materials Sciences
22.03.2017 | Physics and Astronomy
22.03.2017 | Materials Sciences