Stress causes immune cells to stop moving, preventing them from protecting against diseases
Sydney, Australia | Xinhua | Australian researchers have discovered that signals produced by nerves in response to stress can stop immune cells from fighting pathogens or tumours.
The study led by Professor of University of Melbourne and Laboratory Head at the Peter Doherty Institute for Infection and Immunity Scott Mueller was published in the journal of Immunity on Thursday.
The findings were made using a special microscopy technique, which allowed the scientists to view live cells in real-time. The research team chose mouse models because the technique is very difficult to do in people as it requires body tissue.
“We know anecdotally that when we are stressed, we are more likely to get sick, but exactly why this occurs has been difficult to define, until now. The imaging showed us that stress caused immune cells to stop moving, preventing them from protecting against disease,” said Mueller.
“Movement is central to how immune cells can get to the right parts of the body to mount an immune response against infections or tumours, so it was surprising to see that the stress signals had such a rapid and dramatic effect on how immune cells move around.”
“We also showed that it was different types of immune cells that were affected, and that it can occur in many different parts of the body.”
The researchers thought that the finding showed how stress could dramatically impact the body’s immune system, and may provide new avenues to overcome the negative effects of stress on immunity.
“For instance, cancer patients face increased stress that can contribute to a decreased ability of the body to fight the disease, and we might be able to use our findings to improve immune responses to those patients,” Mueller said.
There were many reasons why the body produces neurotransmitters, signals from the nervous system that could control heart rate and blood pressure for instance, according to the researchers. They also found nerves do not halt immune cells in all instances, only in response to significant stress.
“It’s also difficult to study what kind of stress signals could induce the immune cells to stop. Is it a sudden shock or chronic psychological stress?” Mueller said.
He said the researchers will continue to study the mechanisms of this process, and use the findings to test if immune responses to cancer are suppressed by sympathetic nervous system stress signals, and if they can use this to boost anti-cancer responses in patients.
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Xinhua