Special cells stored in body fat remember pathogens, making them more effective at fighting infection than other immune cells, new research reveals.
A new National Institutes of Health study found that these memory T-cells, which are found throughout the body, are very densely packed into fat tissues in mammals.
The researchers discovered that when fat was transferred from an animal that had been exposed to a particular bacteria to one that had not, the unexposed animal was able to fight off infection as well as the one that had already encountered the bacteria.
Their findings suggest that fat transplants could someday be used to help fight off diseases that might otherwise be fatal.
Fat contains dense stores of memory T-cells (pictured in gray) that remember infections (pictured in purple) and kick into high gear to fight them more effectively the next time around
As much as we fight fat, it is essential not only to our energy stores, but to the maintenance of body temperature and systems.
However, as the NIH researchers point out in their study, published in Immunity, fat's role in the immune system has not been well understood.
The relationship between the metabolic system that helps us convert fat into energy and our immune system is a complex one that scientists have begun taking a closer look at in recent years.
While too much fat can throw that relationship out of balance and weaken the immune system, the new NIH findings suggest that fat may be getting a worse rap than it deserves, as it fights infections.
T-cells are a kind of white blood cell produced in bone marrow, and distributed through the body's lymphatic system.
The two types of T-cells - known as helper cells and killer cells - work together to fight off infection with something foreign, like a bacteria, enters the body.