Scientists have come one step closer to rewinding the clock on the human immune system, allowing it to fight disease more effectively, according to

In a study published in the most recent issue of the Journal of Immunology, University College of London researchers discovered how to re-animate white cells that had gone dormant.

Before this study, scientists believed that white cells became inactivated throughout life as they reproduced and fought off various illnesses and infections. As their white cell count drops, older people become weaker and less capable of fighting infection. Infections are one of the leading causes of death of the elderly, according to the Centers for Disease Control.

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Scientist thought that the lifespan of white cells was determined by the length of their telomeres, or tips at the end of their DNA. They believed that as cells aged, their telomeres got shorter, until they finally became inactive.

But the University of London researchers found that some cells with long telomeres were also inactive, indicating that something other than telomere length was at work in determining cell activity. They were able to "jam" the pathway that caused the inactivity. Now they are looking to develop medicines and other treatments that will re-animate these cells in seniors, giving their immune systems a temporary boost so they can fight off infections.