Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Single microRNA fine-tunes innate immune response

Findings: A single microRNA, microRNA-223, in mice controls the production and activation of granulocytes, white blood cells essential for host defense against invading pathogens.

Relevance: This is the first microRNA shown to play a crucial role in the innate immune response. Absence of microRNA-223 increased the production, differentiation and activation of granulocytes, causing tissue inflammation and damage. Increased production of microRNA-223 may reduce inflammatory conditions and thus the effects of inflammatory diseases such as acute lung respiratory disease syndrome.

Over the last few years scientists have discovered hundreds of microRNAs—tiny RNAs that regulate the expression of protein-coding genes. However, the functions of these novel molecules in mammals are largely unknown.

Now, scientists in the lab of Whitehead Fellow Fernando Camargo have discovered the first microRNA shown to play a key role in the immune system’s early warning system—the innate immune response. The research, published online on February 17 by Nature, reveals that microRNA-223 controls the production and activation of granulocytes, white blood cells essential for host defense against invading pathogens. The findings may have implications for the treatment of inflammatory conditions as well as leukemia.

“MicroRNA-223 is unique because its expression is entirely restricted to a specific branch of the immune system,” says Camargo. “We found that microRNA-223 is crucial for the development and function of the innate branch of the immune system. Our work suggests that microRNA-223 physiologically fine-tunes both the generation and function of granulocytic cells, delimiting their production and dampening their activation.”

The study indicated that microRNA-223 targets Mefc2, a transcription factor that promotes the expansion of granulocyte cell progenitors. (Transcription factors are proteins that regulate gene expression.) By knocking out Mefc2, the authors found that some of the effects caused by microRNA-223 were eliminated.

The researchers demonstrated that mice modified to lack microRNA-223 expression had up to three times as many granulocytes in their bone marrow and blood. Moreover, the granulocytes matured more rapidly and then reacted more aggressively to stimuli. This increased activity caused tissue inflammation and damage within the lungs with age or, in an acute inflammation model, within the liver, muscle and kidneys.

“If you have an infection in the lungs, granulocytes will migrate to the site of the infection and attack,” says Jonathan Johnnidis, first author of the paper and a former technician in the Camargo lab, and now a graduate student in molecular biology at the University of Pennsylvania. “Once the infection is cleared granulocytes usually migrate away and settle down. However, in this case they didn’t stand down after they were done fighting. Instead they continued an inflammatory response that did more damage.”

“Like a hand grenade once you pop the trigger out, these granulocytes are going to explode, regardless of whether they are surrounded by healthy tissue or harmful bacteria,” adds Camargo. “Lack of microRNA-223 makes it much easier to activate the grenade.”

Camargo plans to further investigate the effect of this microRNA on disease. “Our work suggests that microRNA-223 physiologically fine-tunes both the generation and function of granulocytic cells, delimiting their production and preventing excessive activation,” he says. “Also, since many forms of leukemia express diminished levels of microRNA-223, we are investigating how silencing of this microRNA may contribute to the development of that disease.”

Cristin Carr | EurekAlert!
Further information:

Further reports about: Camargo MicroRNA activation fine-tunes granulocyte immune inflammatory innate microRNA-223

More articles from Life Sciences:

nachricht Novel mechanisms of action discovered for the skin cancer medication Imiquimod
21.10.2016 | Technische Universität München

nachricht Second research flight into zero gravity
21.10.2016 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

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

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>