Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Supporting the troops

04.04.2011
In the absence of vitamin A, the body loses immune cells that put the brakes on the earliest stages of infection

Scientists have recognized the immune-boosting capabilities of vitamin A for the better part of a century, even without fully understanding how it helps the body fight off bacteria and viruses.

“Soon after its discovery, vitamin A was termed ‘the anti-infective vitamin’ and was widely used to enhance recovery; but with the introduction of antibiotics, the therapeutic use of vitamin A diminished,” says Sidonia Fagarasan of the RIKEN Center for Allergy and Immunology in Yokohama.

Fagarasan and her colleagues have now revealed how vitamin A deficiency can critically undermine the body’s initial defense against infection[1]. B1 cells within the peritoneal cavity (PEC), the space surrounding the intestines and other organs, are important ‘first responders’ to the presence of pathogens (Fig. 1). Upon activation, B1 cells mature into cells that produce immunoglobulin M (IgM) and A (IgA) antibodies that target bacteria and viruses in the bloodstream and gut, respectively. “These cells usually act at the early time window after infection, thus preventing the expansion of microorganisms,” explains Fagarasan.

Mikako Maruya, a young researcher with her team, observed dramatic depletion of PEC B1 cells in mice fed a vitamin A-free diet, which grew more severe with age. Accordingly, these vitamin A-deficient (VAD) animals also produced lower levels of both IgA and IgM, and failed to marshal an effective antibody response following injection with pneumonia vaccine. B1 cells transplanted from healthy donors to VAD animals showed impaired proliferation, and considerably dwindled in number over the course of a week. Importantly, bone marrow-derived stem cells from VAD mice retained the capacity to give rise to B1 cells, although they failed to do so in the absence of vitamin A.

The key turned out to be nuclear factor of activated T cells 1 (NFATc1), a transcription factor protein that regulates expression of numerous important genes in B1 cells. The researchers observed reduced NFATc1 levels in VAD B1 cells, but found that expression could be largely restored if these mice were injected with ATRA, a product of cellular vitamin A metabolism. This also led to rapid B1 cell proliferation, which increased in number by more than four-fold increase within 10 days of injection.

Motivated by these findings, Fagarasan is now exploring how levels of vitamin A affect other components of the immune response to infection. “We were very excited to discover something that we had never thought about, that active products of vitamin A contribute to the induction of some very important transcription factors,” she says.

The corresponding author for this highlight is based at the Laboratory for Mucosal Immunity, RIKEN Center for Allergy and Immunology

Journal information

[1] Maruya, M., Suzuki, K., Fujimoto, H., Miyajima, M., Kanagawa, O., Wakayama, T. & Fagarasan, S. Vitamin A-dependent transcriptional activation of the nuclear factor of activated T cells c1 (NFATc1) is critical for the development and survival of B1 cells. Proceedings of the National Academy of Sciences USA 108, 722–727 (2011).

gro-pr | Research asia research news
Further information:
http://www.rikenresearch.riken.jp/eng/research/6557
http://www.researchsea.com

Further reports about: Allergy Fagarasan IgA IgM Immunology NFATc1 PEC RIKEN T cells transcription factor vitamin A

More articles from Life Sciences:

nachricht Researchers uncover protein-based “cancer signature”
05.12.2016 | Universität Basel

nachricht The Nagoya Protocol Creates Disadvantages for Many Countries when Applied to Microorganisms
05.12.2016 | Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

IHP presents the fastest silicon-based transistor in the world

05.12.2016 | Power and Electrical Engineering

InLight study: insights into chemical processes using light

05.12.2016 | Materials Sciences

High-precision magnetic field sensing

05.12.2016 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>