Scientist have known for years that people suffering from heavy stress or a bad mood are more likely to feel sick than those under little pressure, but they couldn't definitively explain why.

Now, a group of local researchers say that they can prove the phenomenon is linked to the way cells and molecules transmit information.

Their study was published in the latest issue of Molecular Cell, a renowned American journal.

The discovery could help scientists find ways to regulate the body's immune system through its sympathetic nervous system, according to the study's authors, who work for the Shanghai Institutes for Biological Sciences, an offshoot of the Chinese Academy of Sciences.

"As the basic unit of biological movement, cells receive information from the outside world and transfer these signals to direct all important life activities," said Pei Gang, one of the scientists involving in the research. Many diseases like tumors and problems with the immunity system are due to faulty or delayed information transformation, according to the scientist.

Previously, the scientific community understood the sympathetic nervous system can influence a person's immunity system through a protein, but they didn't understand how it worked molecularly.

(Shanghai Daily May 11, 2004)