US scientists say a protein in the immune system is affected by changes in the body’s circadian rhythm, a genetic mechanism that regulates sleep cycles and metabolic changes.
As the immune system needs to detect an infection before its beginning to fight, researchers analyzed the protein involved in the detection process, Toll-like receptor nine (TLR9), which can spot DNA from bacteria and viruses.
Experiments on mice showed that both the amount of producing TLR9 and the way it functioned were controlled by the body clock and varied through the day.
Immunizing mice at the peak of TLR9 activity improved the immune response, researchers announced. The severity of sepsis in the study depended on the time of day infection started and coincided with changes in TLR9 activity.
“It does appear that disruptions of the circadian clock influence our susceptibility to pathogens,” said lead researcher Professor Erol Fikrig adding the finding could have “important implications for the prevention and treatment of disease.”
Scientists also said people with sepsis, blood poisoning, were at a greater risk of death between 2am and 6am.
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