(Press-News.org) Our bodies produce a family of proteins that recognize and kill bacteria whose carbohydrate coatings resemble those of our own cells too closely, scientists have discovered.
Called galectins, these proteins recognize carbohydrates from a broad range of disease-causing bacteria, and could potentially be deployed as antibiotics to treat certain infections. The results are scheduled for publication in Nature Chemical Biology.
Researchers at Emory University School of Medicine made the discovery with the aid of glass slides coated with an array of over 300 different glycans (carbohydrates found on the surfaces of cells) derived from bacteria, many of which are found in the intestine. One can think of these slides – called microbial glycan microarrays – as wardrobes displaying a variety of clothes worn by gut bacteria.
"Many microbes cover themselves with glycans that somewhat resemble our own cells," says Richard D. Cummings, PhD, professor and chair of the Department of Biochemistry at Emory University School of Medicine. "That limits how well the immune system can use antibodies to respond to those microbes."
To prevent auto-immune attack, our bodies usually don't make antibodies against molecules found on our own cells. That leaves gaps in our defenses that bacteria could exploit. Several of those gaps are filled by galectins, the researchers found.
The discovery expands upon an initial finding, published in Nature Medicine in 2010, describing galectins that recognize and kill bacteria that express the human blood group B antigen.
The Emory researchers collaborated with the laboratory of James C. Paulson, PhD, at the Scripps Research Institute (TSRI). Co-first authors of the paper are Sean Stowell, MD/PhD (a resident in in laboratory and transfusion medicine at Emory), Connie Arthur, PhD (postdoctoral fellow at Emory with Stowell), and research assistant Ryan McBride at TSRI.
In contrast to antibodies, the galectins kill the bacteria directly, without needing other parts of the immune system to pile on. The researchers identified several varieties of bacteria (Pseudomonas aeruginosa, Providencia alcalifaciens, Klebsiella pneumoniae, and Serratia marcescens, for example) targeted for killing by galectins. In some cases, only certain strains of a given bacteria were vulnerable, because only those strains carried the target glycan.
"These studies have opened the way to understanding the ways in which adaptive or antibody-based factors work together with innate or galectin-based factors to give us immunity against a broad range of microbes," Cummings says.
In addition, the microarray technology provides tools to study glycan-binding antibodies and galectins in populations, he says.
"These studies use tiny amounts of blood – just a few drops – and show how glycan microarrays could supersede previous technology," he says. "Using these tools, investigators could identify developmental- and age-specific differences in anti-microbial glycan antibodies in humans, which may predict susceptibility to disease."
INFORMATION: END
Galectins direct immunity against bacteria that employ camouflage
Carbohydrate-binding proteins fill in gaps in immune defenses
2014-05-11
ELSE PRESS RELEASES FROM THIS DATE:
Study finds patients AFib at higher risk of dementia when meds out of range
2014-05-10
A new study by researchers at the Intermountain Medical Center Heart Institute in Salt Lake City has found that atrial fibrillation patients who are on blood thinning medications are at higher risk of developing dementia if their doses are not in the optimal recommended range.
The study of more than 2,600 AFib patients found they are significantly more likely to develop dementia when using medicines to prevent blood clots, such as warfarin, when their dosing is too high or too low for an extended period of time.
Findings from the study will be presented at the 2014 ...
Bee biodiversity boosts crop yields
2014-05-10
Research from North Carolina State University shows that blueberries produce more seeds and larger berries if they are visited by more diverse bee species, allowing farmers to harvest significantly more pounds of fruit per acre.
"We wanted to understand the functional role of diversity," says Dr. Hannah Burrack, an associate professor of entomology at NC State and co-author of a paper on the research. "And we found that there is a quantifiable benefit of having a lot of different types of bees pollinating a crop."
The researchers looked at blueberries in North Carolina ...
Scientists find gene behind a highly prevalent facial anomaly
2014-05-10
CAMBRIDGE, Mass. (May 9, 2014) – Whitehead Institute scientists have identified a genetic cause of a facial disorder known as hemifacial microsomia (HFM). The researchers find that duplication of the gene OTX2 induces HFM, the second-most common facial anomaly after cleft lip and palate.
HFM affects approximately one in 3,500 births. While some cases appear to run in families, no gene had been found to be causative. That is until Whitehead Fellow Yaniv Erlich and his lab set out to do just that. Their work is described in this week's issue of the journal PLOS ONE.
Patients ...
Cardiac screening test may help determine who should take aspirin to prevent heart attack
2014-05-09
MINNEAPOLIS, MN – May 6, 2014 – For over 30 years, aspirin has been known to prevent heart attacks and strokes, but who exactly should take a daily aspirin remains unclear. New research published today in Circulation: Cardiovascular Quality and Outcomes shows that your coronary artery calcium (CAC) score, a measurement of plaque in the arteries that feed the heart, may help determine whether or not you are a good candidate for aspirin.
"Many heart attacks and strokes occur in individuals who do not appear to be at high risk," states lead author, Michael D Miedema, MD, ...
NASA's TRMM Satellite see spring storms hit the US Great Plains
2014-05-09
VIDEO:
The TRMM satellite flew above tornado spawning thunderstorms in the southern United States on May 9, 2014 at 0115 UTC. This simulated 3-D TRMM animation shows the location of intense...
Click here for more information.
The Tropical Rainfall Measuring Mission or TRMM satellite captured rainfall and cloud height information about the powerful thunderstorms and severe weather that affected the Great Plains over May 8 and 9.
Severe weather extended from Minnesota to southern ...
Plugging leaky blood vessels to save vision
2014-05-09
TORONTO – A new drug approach has been developed for safer clean-up of deformed blood vessels in the eye by a research team at the Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital in Toronto.
The growth of malformed blood vessels that can burst is a leading cause of vision loss in North America. Retinopathy and retina degeneration are associated with premature birth, with diabetes, and with increasing age.
Research just published by Dr. Andras Nagy and co-authors shows both safety and effectiveness in their bioengineered compound when treating retinopathy ...
Paleontologists discover new fossil organism
2014-05-09
RIVERSIDE, Calif. — Scientists at the University of California, Riverside have discovered a fossil of a newly discovered organism from the "Ediacara Biota" — a group of organisms that occurred in the Ediacaran period of geologic time.
Named Plexus ricei and resembling a curving tube, the organism resided on the Ediacaran seafloor. Plexus ricei individuals ranged in size from 5 to 80 centimeters long and 5 to 20 millimeters wide. Along with the rest of the Ediacara Biota, it evolved around 575 million years ago and disappeared from the fossil record around 540 million ...
Discovery links rare, childhood neurodegenerative diseases to common problem in DNA repair
2014-05-09
(MEMPHIS, Tenn. – May 9, 2014) St. Jude Children's Research Hospital scientists studying two rare, inherited childhood neurodegenerative disorders have identified a new, possibly common source of DNA damage that may play a role in other neurodegenerative diseases, cancer and aging. The findings appear in the current issue of the scientific journal Nature Neuroscience.
Researchers showed for the first time that an enzyme required for normal DNA functioning causes DNA damage in the developing brain. DNA is the molecule found in nearly every cell that carries the instructions ...
Longevity gene may boost brain power
2014-05-09
Scientists showed that people who have a variant of a longevity gene, called KLOTHO, have improved brain skills such as thinking, learning and memory regardless of their age, sex, or whether they have a genetic risk factor for Alzheimer's disease. Increasing KLOTHO gene levels in mice made them smarter, possibly by increasing the strength of connections between nerve cells in the brain. The study was partly funded by the National Institutes of Health.
"This could be a major step toward helping millions around the world who are suffering from Alzheimer's disease and ...
Autism-related protein shown to play vital role in addiction
2014-05-09
BELMONT - In a paper published in the latest issue of the neuroscience journal Neuron, McLean Hospital investigators report that a gene essential for normal brain development, and previously linked to Autism Spectrum Disorders, also plays a critical role in addiction-related behaviors.
"In our lab, we investigate the brain mechanisms behind drug addiction – a common and devastating disease with limited treatment options," explained Christopher Cowan, PhD, director of the Integrated Neurobiology Laboratory at McLean and an associate professor of Psychiatry at Harvard Medical ...
LAST 30 PRESS RELEASES:
Pink skies
Monkeys are world’s best yodellers - new research
Key differences between visual- and memory-led Alzheimer’s discovered
% weight loss targets in obesity management – is this the wrong objective?
An app can change how you see yourself at work
NYC speed cameras take six months to change driver behavior, effects vary by neighborhood, new study reveals
New research shows that propaganda is on the rise in China
Even the richest Americans face shorter lifespans than their European counterparts, study finds
Novel genes linked to rare childhood diarrhea
New computer model reveals how Bronze Age Scandinavians could have crossed the sea
Novel point-of-care technology delivers accurate HIV results in minutes
Researchers reveal key brain differences to explain why Ritalin helps improve focus in some more than others
Study finds nearly five-fold increase in hospitalizations for common cause of stroke
Study reveals how alcohol abuse damages cognition
Medicinal cannabis is linked to long-term benefits in health-related quality of life
Microplastics detected in cat placentas and fetuses during early pregnancy
Ancient amphibians as big as alligators died in mass mortality event in Triassic Wyoming
Scientists uncover the first clear evidence of air sacs in the fossilized bones of alvarezsaurian dinosaurs: the "hollow bones" which help modern day birds to fly
Alcohol makes male flies sexy
TB patients globally often incur "catastrophic costs" of up to $11,329 USD, despite many countries offering free treatment, with predominant drivers of cost being hospitalization and loss of income
Study links teen girls’ screen time to sleep disruptions and depression
Scientists unveil starfish-inspired wearable tech for heart monitoring
Footprints reveal prehistoric Scottish lagoons were stomping grounds for giant Jurassic dinosaurs
AI effectively predicts dementia risk in American Indian/Alaska Native elders
First guideline on newborn screening for cystic fibrosis calls for changes in practice to improve outcomes
Existing international law can help secure peace and security in outer space, study shows
Pinning down the process of West Nile virus transmission
UTA-backed research tackles health challenges across ages
In pancreatic cancer, a race against time
Targeting FGFR2 may prevent or delay some KRAS-mutated pancreatic cancers
[Press-News.org] Galectins direct immunity against bacteria that employ camouflageCarbohydrate-binding proteins fill in gaps in immune defenses