Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Gamma interferon a wake-up call for stem cell response to infection

Most of the time, the body's blood-forming (hematopoietic) stem cells remain dormant, with just a few producing blood cells and maintaining a balance among the different types.

However, invading bacteria can be a call-to-arms, awaking the sleeping stem cells and prompting them to produce immune system cells that fight the foreign organisms. The "bugler" that awakes the stem cells in this battle is gamma interferon, a front-line protein defender against bacterial infection, said researchers from Baylor College of Medicine ( in a report that appears in the current issue of the journal Nature (

"We are looking at the normal function of stem cells," said Dr. Margaret Goodell (, professor of molecular and human genetics at BCM and director of the Stem Cells and Regenerative Medicine (STaR) ( Center. She is the report's senior author. "One of those is to respond to an infection."

Goodell and her colleagues knew that cells farther along in the differentiation process responded to infection, increasing the production of immune cells.

"We were sure there was a mechanism by which hematopoietic stem cells respond to infection, but it was not obvious," she said. They started their work with gamma interferon because they knew it played an important role in bacterial infection.

The collaboration and talents of two researchers in her laboratory – first co-authors Drs. Megan T. Baldridge and Katherine Y. King – facilitated the work with mice that led to this finding, said Goodell. Both are at BCM.

"I think our findings represent an exciting new avenue for studying hematopoiesis," said King. "By viewing the hematopoietic stem cell as the source of the immune system, we are finding fundamental ways in which the immune response affects bone marrow. This is the first time that anyone has extensively studied hematopoietic stem cells in the context of an in vivo model (a living organism) of infection."

"As a specialist in infectious diseases, I see many patients whose bone marrow no longer produces sufficient blood cells as a consequence of their infection. This is particularly relevant in chronic infections such as mycobacterial diseases (that include tuberculosis) and AIDS," said King. "Our studies lend insight into the causes of this decrease in bone marrow function during such infections, and I hope the work will someday lead to new therapies."

Studies in mice with a chronic or long-term infection called Mycobacterium avium show that a greater proportion of a particular subset of their cells called long-term hematopoietic (blood-forming) stem cells are active. Gamma interferon prompts this activity. Mice that lack gamma interferon have fewer of these stem cells active during infection.

These findings show that gamma interferon not only activates stem cells during infection, but also regulate stem cells in normal times, enabling them to maintain the types of blood cells that exist in proportion or homeostasis.

"Our model predicts that bacterial infection detected by sentinel immune cells stimulates the increased release of gamma interferon, which then travels through the blood stream to activate HSCs (hematopoietic stem cells) in the bone marrow, leading to expansion and mobilization of the immune progenitor pool (the cells that ultimately produce immune system cells)," the researchers wrote.

They found that sustained activity by the hematopoietic stem cells can lead to at least transient problems with the quality of the stem cells and their abilities to stimulate production of more immune system cells.

"One of the most important things we found is the chronic infections (such as tuberculosis or HIV/AIDS) may be lead to bone marrow exhaustion," said Baldridge. "We knew that a condition called anemia of chronic disease exists, and this could be one of the contributing factors."

Funding for this work came from the National Institute of Diabetes and Digestive and Kidney Diseases (, the Adeline B. Landa Fellowship of the Texas Children's Hospital Auxiliary, the Simmons Foundation Collaborative Research Fund (, the National Heart, Lung and Blood Institute ( and the National Institute of Biomedical Imaging and Bioengineering (

Glenna Picton | EurekAlert!
Further information:

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 >>>