Satellite Banner
Technology
Networks
Scientific Communities
 
Become a Member | Sign in
Home>News>This Article
  News
Return

NIAID Study Identifies Immune Sensors of Malnutrition

Published: Monday, January 27, 2014
Last Updated: Monday, January 27, 2014
Bookmark and Share
Leading research to understand, treat, and prevent infectious, immunologic, and allergic diseases.

In a new study, NIAID scientists describe how the immune system responds to malnutrition by adjusting the types of immune cells in the gastrointestinal tract. In a mouse model of vitamin A deficiency, they observed the expansion of type 2 innate lymphoid (ILC2) cells, which are essential for immune responses against nutrient-depleting helminth, or parasitic worm, infections. The study appears in the January 23, 2014, online issue of Science.

Background
The impact of nutrition on the immune system is an important research focus with broad impact. Vitamin A deficiency is estimated to affect up to 250 million children worldwide, particularly in regions where chronic helminth infections and malnutrition are prevalent. It is the leading cause of preventable blindness in children and is associated with higher rates of severe diarrheal disease.

In the body, vitamin A is broken down into a product called retinoic acid (RA), which is essential for growth and development. RA also is necessary for the immune system, and without it, classes of T cells fail to develop or function, enhancing susceptibility to infections.

Yasmine Belkaid, Ph.D., and her research team in NIAID's Laboratory of Parasitic Diseases reasoned that the immune system compensates for the effects of vitamin A deficiency because people can survive for extended periods of malnutrition. One of the minimum requirements for survival is to maintain immunity at barrier surfaces, like the gastrointestinal tract and lungs. These locations are enriched for innate lymphoid cells, which come in three classes: ILC1, ILC2, and ILC3. The NIAID team sought to examine how vitamin A deficiency impacts ILCs and barrier defenses.

Results of Study
Dr. Belkaid and colleagues used a mouse model of vitamin A deficiency to examine how malnutrition affects immunity along the gastrointestinal tract. In mice lacking vitamin A or RA, the ILC3 subset, which typically provides antibacterial immunity, was diminished in the gut. As such, the malnourished mice were more susceptible to infection with the bacterium Citrobacter rodentium, a model for the disease-causing forms of Escherichia coli.

Surprisingly, however, mice lacking vitamin A or RA had significantly more ILC2 in the gut. The ILC2 subset typically provides immune defense against helminths. Compared to nourished mice, the malnourished ones had similar or even better immune responses against infection with the parasitic worm Trichuris muris.

Significance
This study identifies ILCs as sensors of malnutrition that alter gut immunity in response to diet. For vitamin A deficiency, RA is the key switch that directs these changes. Contrary to common belief, this work shows that nutrient deficiency does not equal global immunosuppression, as antihelminth immunity is actually promoted and enhanced.

The results of this study also correlate with observations of children who suffer from vitamin A deficiency. They are more susceptible to gastrointestinal bacterial infections but also tend to live in areas with chronic helminth infections, which compete with their hosts for essential nutrients.

While more work is needed to address the role of malnutrition on ILCs in people, this shift in cell types may be a response to temporarily boost survival against debilitating helminth infections during malnutrition.

Next Steps
The researchers will examine how other nutrient deficiencies affect the immune system and how this may influence vaccination outcomes. Vaccines are developed to enhance specific immune responses, but the nutritional state of intended recipients is rarely incorporated into studies. Understanding how nutrition affects the immune system promises to help optimize vaccine design and development, particularly for diseases that affect regions where malnutrition is prevalent.

The ILC2 subtype also is important for tissue repair. Understanding how nutrition influences ILC2 activity will provide new insight on effective therapies for inflammatory diseases like Crohn's disease, an inflammatory bowel disorder, and autoimmunity.


Further Information

Join For Free

Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 3,300+ scientific posters on ePosters
  • More Than 4,900+ scientific videos on LabTube
  • 35 community eNewsletters


Sign In



Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into TechnologyNetworks.com you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.

Related Content

Experimental MERS Vaccine Shows Promise in Animal Studies
A two-step regimen of experimental vaccines against Middle East respiratory syndrome (MERS) prompted immune responses in mice and rhesus macaques, report National Institutes of Health scientists who designed the vaccines.
Thursday, July 30, 2015
New Mouse Study Method Enables Comparative Vaccine Studies for Tularemia
The study appears online in Clinical Vaccine and Immunology.
Wednesday, January 07, 2015
NIH Expands Nationwide Network of Vaccine and Treatment Evaluation Units
A nationwide group of institutions that conducts clinical trials has been awarded nine contracts to strengthen and broaden the scope of its research.
Friday, September 27, 2013
Scientists Identify Gene that Allows Malaria Parasite to Survive in Mosquitoes
NIAID researchers have identified a gene that helps malaria-causing parasites elude the mosquito immune system, allowing the microbes to transmit efficiently to people when the insect takes a blood meal.
Friday, May 10, 2013
Barrier in Mosquito Midgut Protects Invading Pathogens
Discovery May Inform New Strategies for Blocking Malaria Transmission
Friday, March 12, 2010
Scientific News
Breakthrough Flu Vaccine Inhibited by Pre-existing Antibodies
Universal truths – how existing antibodies are sabotaging the most promising new human flu vaccines.
Liquid Biopsies: Miracle Diagnostic or Next New Fad?
Thanks to the development of highly specific gene-amplification and sequencing technologies liquid biopsies access more biomarkers relevant to more cancers than ever before.
New Medication Shows Promise Against Liver Fibrosis in Animal Studies
Liver fibrosis is a gradual scarring of the liver that puts people at risk for progressive liver disease and liver failure.
Raw Eggs Deemed Safe to Eat
A report published today by the Advisory Committee on the Microbiological Safety of Food (ACMSF) into egg safety has shown a major reduction in the risk from salmonella in UK eggs.
Monitoring TTX Toxin in Shellfish
In a number of small studies, mussels and oysters from the eastern and northern part of the Oosterschelde in Holland were found to contain tetrodotoxin (TTX).
Gene Terapy for Muscle Wasting Developed
New gene therapy could save millions of people suffering from muscle wasting disease.
NIH Begins Yellow Fever Vaccine Trial
NIH has initiated an early-stage clinical trial of a vaccine to protect against yellow fever.
Gene-Editing 'Toolbox' Targets Multiple Genes Simultaneously
Researchers have designed a system that modifies, or edits, multiple genes in a genome at once while minimising unintentional effects.
Detecting Alzheimer's with Smell Test
Odour identification test may offer low-cost alternative for predicting cognitive decline and detecting early-stage Alzheimer’s disease.
Antibody Drug Shows Promise in HIV Treatment
Researchers are a step closer to an alternative HIV treatment that has the potential for lasting effects and less frequent dosing.
Scroll Up
Scroll Down
Skyscraper Banner

Skyscraper Banner
Go to LabTube
Go to eposters
 
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
3,300+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
4,900+ scientific videos
Close
Premium CrownJOIN TECHNOLOGY NETWORKS PREMIUM FOR FREE!