Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study identifies key player in the body’s immune response to chronic stress

05.09.2007
Osteopontin (OPN), a protein molecule involved in many different cellular processes, plays a significant role in immune deficiency and organ atrophy following chronic physiological stress, resulting in increased susceptibility to illness. These findings appear in the September 4th issue of the Proceedings of the National Academy of Sciences.

The study is supported by the National Space Biomedical Research Institute (NSBRI), the Busch Biomedical Research Grant, National Multiple Sclerosis Society, and Rutgers Technology Commercialization Fund. Authors on the paper include Dr. Yufang Shi, investigator on NSBRI’s Radiation Effects Team and professor of molecular genetics, microbiology and immunology at the University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School, Dr. David T. Denhardt, one of the discoverers of OPN, professor of cell biology and neuroscience at Rutgers, the State University of New Jersey, and Kathryn X. Wang, graduate student in the Rutgers Graduate Program in Cell and Developmental Biology.

“Following periods of prolonged physical stress such as when astronauts live in microgravity, white blood cells that fight disease, called lymphocytes, die at an increased rate and immune system organs like the thymus and spleen lose mass and begin to atrophy,” said Dr. Shi.

Immune system organs include the thymus, spleen, lymph nodes and bone marrow.

“By determining the role of lymphocyte death in a stressed immune system, we may be able to develop therapies to maintain a healthy immune system, which can help in space and in clinical settings to prevent and treat malignancy and infections,” Shi said.

It is known that spaceflight and long periods of physiological stress cause changes in the immune system. “Until now, the role of OPN in the stress response of immune organs has never been examined,” Shi said.

Evidence suggests that astronauts may suffer increased rates of infection after flight. Through an animal study, Shi and colleagues simulated spaceflight conditions to investigate its effects on the immune system. They found that infection-fighting white blood cells inappropriately die off in large numbers, leading to immune-organ atrophy and the decreased ability of the immune system to protect the body from illness.

The team studied two types of mice, one group with the normal OPN gene and another group lacking this gene. The mice experienced three days of hindlimb unloading, a widely used technique to simulate the physiologic changes that astronauts experience during spaceflight. With this technique, body fluids shift similarly to how they do in microgravity (toward the head instead of toward the extremities) and immune system changes occur.

Mice of both types made up the control groups, which did not undergo unloading.

After three days, the researchers compared the mice with normal OPN and the OPN-lacking mice. The normal OPN mice experienced weight loss, spleen and thymus atrophy, and a reduced number of white blood cells. In addition, increased levels of corticosterone, a steroid that contributes to the death of white blood cells, were found only in the normal OPN mice studied. By contrast, the mice lacking the OPN gene showed statistically insignificant changes in weight and the levels of corticosterone, and were more similar to the control group.

“White blood cell death in the spleen and thymus was evident only in the mice with normal OPN,” Shi said. “Since white blood cells were dying rather than increasing, that indicates partly why immune system organs atrophy during prolonged physical stress.”

The team concluded that under chronic physical stress, OPN must be present for the increase in corticosterone, which leads to atrophy and white blood cell death.

Shi hopes that this finding will lead to preventative treatments in the future.

“Already we’re researching an antibody that can remove OPN from blood serum. Perhaps one day, we can turn this research into a therapy to counteract white blood cell death in immune system organs and keep humans healthier during times of prolonged physical stress,” Shi said.

Shi and colleagues want to better understand the mechanisms through which stress affects the immune system, so they can prevent illness in space and help those who suffer from illness following physiological stress here on Earth.

NSBRI projects address space health concerns such as bone and muscle loss, cardiovascular changes, balance problems, sleep disturbances, radiation exposure, nutrition, physical fitness, rehabilitation, remote-treatment medical technologies, and neurobehavioral and psychosocial factors. Research findings will also impact the understanding and treatment of similar medical conditions experienced on Earth.

NSBRI, funded by NASA, is a consortium of institutions studying the health risks related to long-duration spaceflight. The Institute’s science, technology and education projects take place at more than 70 institutions across the United States.

Lauren Hammit | NSBRI
Further information:
http://www.nsbri.org/NewsPublicOut/Release.epl?r=105

More articles from Studies and Analyses:

nachricht New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)

nachricht Reusable carbon nanotubes could be the water filter of the future, says RIT study
30.03.2017 | Rochester Institute of Technology

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

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

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

Im Focus: Using graphene to create quantum bits

In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.

In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

Physicists discover mechanism behind granular capillary effect

24.05.2017 | Physics and Astronomy

Measured for the first time: Direction of light waves changed by quantum effect

24.05.2017 | Physics and Astronomy

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>