Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

To keep or not to keep a hookworm

30.03.2016

UC Riverside-led research team identifies key protein that by protecting the body from damage in hookworm infections ensures benefits outweigh risks

Researchers in the School of Medicine at the University of California, Riverside have identified an immune protein in mice that is quickly triggered in the body following infection and serves to protect the body's tissues. Called "RELMalpha," this protein, whose homologue in humans is called "resistin," is responsible more for protecting the body than attacking the parasite.


Immunofluorescent image shows cross-section of hookworm (red) invading the small intestine (blue) leading to recruitment of macrophages (green).

Credit: Jay Patel, Nair lab, UC Riverside.

As mammals, we have an immune system to fight pathogens that attack us. Because pathogens do us damage, the body naturally releases proteins to kill the pathogens. But these cytokines--proteins made by immune cells--can also attack the body's tissues and damage them. RELMalpha, made by mice to dampen the immune system response, focuses on protecting the body's tissues. Resistin is expected to function similarly in humans.

"This is counterintuitive," said Meera G. Nair, Ph.D., an assistant professor of biomedical sciences, whose lab led the research that focused on the hookworm as the parasite of study. "We think the immune system is all about killing the parasite. But that's not what RELMalpha sets out to do. It is important evidence that mammals have regulatory systems in place not to kill pathogens, but instead to dampen the immune response because this, overall, benefits the host."

Study results appear in the April 1 issue of the journal Infection and Immunity.

Hooked on worms

In her career, Nair has done considerable research on hookworms, soil-transmitted nematodes that infect an estimated 2 billion people worldwide--mostly in developing countries where sanitation is poor and people are often barefoot. After penetrating the skin, the hookworm--about 5 millimeters in length--travels from the bloodstream to the lung. Nair explained that the hookworm proceeds to damage the lung, the first organ it infects. When blood vessels break and hemorrhaging follows, the hookworm feeds on the blood (it cannot, however, survive in blood). When it is coughed up and swallowed, it then travels to the gut, the second organ it infects.

"The hookworm could not reach the gut if it didn't use the lung," Nair said. "In the gut, it releases thousands of eggs, which then go into the feces, completing the cycle. This is why infection is prevalent where lack of sanitation is also common, where, say, open defecation is practiced."

For their lab experiments, Nair's team used mice that were genetically deficient, meaning they lacked RELMalpha. The researchers then infected the mice with hookworms. The mice killed the worms but did not survive themselves, being unable to recover from the worm infection, which damaged their lungs.

When such genetically deficient mice were given a low dose of worms, the mice managed to kill the worms faster. But they incurred damage to their bodies. Were the mice to have RELMalpha, the researchers posit, their lung tissues would have been better protected.

Death versus worm burdens

"If you had a choice between having a parasite in your body or you dying from trying to kill it, you would choose to have the parasite live in your body," Nair explained. "Worm parasites are exceptionally good at that. They live with us for long periods without causing much damage. Essentially, a partnership is set up so that both the host and worm benefit. Worms, one of the most complex pathogens, have evolved to be the ideal parasite. They do not want you to die because that would mean they could not survive either. At doing this balancing act between inflammation and immunity, worms may be better than all other pathogens."

Nair noted that there are no vaccines available to fight worm infections. Unfortunately, distributing drugs for a disease that infects billions of people is costly and unfeasible, she said.

"RELMalpha appears to be the pivot on which the balance between inflammation and immunity is struck," she said. "This is likely true in humans as well, where resistin, the human equivalent of RELMalpha, is highly expressed in worm infections." The lab's next focus will be to investigate human resistin in this context.

###

Nair was joined in the research by Gang Chen (first author of the research paper), a principal scientist; Spencer H. Wang, a junior specialist at UCR; Jessica C. Jang, a UCR graduate student; and Justin I. Odegaard, a pathologist at UC San Francisco.

Nair was funded by a grant from the National Institutes of Health, specifically the National Institute of Allergy and Infectious Diseases. She has been invited to speak at the prestigious Gordon Research Conference on Tropical Infectious Diseases, which will be held next year in Galveston, Texas.

The University of California, Riverside (http://www.ucr.edu) is a doctoral research university, a living laboratory for groundbreaking exploration of issues critical to Inland Southern California, the state and communities around the world. Reflecting California's diverse culture, UCR's enrollment has exceeded 21,000 students. The campus opened a medical school in 2013 and has reached the heart of the Coachella Valley by way of the UCR Palm Desert Center. The campus has an annual statewide economic impact of more than $1 billion. A broadcast studio with fiber cable to the AT&T Hollywood hub is available for live or taped interviews. UCR also has ISDN for radio interviews. To learn more, call (951) UCR-NEWS.

Media Contact

Iqbal Pittalwala
iqbal@ucr.edu
951-827-6050

 @UCRiverside

http://www.ucr.edu 

Iqbal Pittalwala | EurekAlert!

More articles from Health and Medicine:

nachricht Team discovers how bacteria exploit a chink in the body's armor
20.01.2017 | University of Illinois at Urbana-Champaign

nachricht Rabies viruses reveal wiring in transparent brains
19.01.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>