Turning older as a human kind of sucks, because things don’t retain their properties and functions that they had during youth. Several products seek to remedy the cosmetic appearance of aging through wrinkle creams and hair dyes, but there hasn’t been much that could be done about internal organs—until now. A new study led by Clare Blackburn of the University of Edinburgh has shown the ability to actually regenerate a thymus for the first time. The results were published in an open-access format in the journal Development.
The thymus is located just above the heart and is the organ responsible for maturing thymocytes into various T lymphocytes, otherwise known as T cells. These cells perform critical immune functions. At birth, the thymus is relatively large when compared to the heart. Over time, the thymus begins to diminish in size and function. By the time adulthood is reached, the thymus is about 25-30% the size it was at puberty.
Blackburn’s team found that there is a natural mechanism responsible for the aging process of the thymus. A protein synthesized in the thymus, FOXN1, regulates the organ’s gene expression. When additional quantities of FOXN1 were added to the thymus, they researchers were able to direct to influence how stem cells differentiated. Those stem cells were instructed to rebuild the thymus, rejuvenating it to a prior, youthful state.
Though the team did show that it was possible to enlarge the thymus, they did not show whether or not T cell production increased and had any effect on the immune system. Now that they know the technique works, future studies will investigate if rebuilding the thymus does create a change in immune system function. If successful, this technique could possibly be used in humans. This could help protect the elderly, who are more susceptible to diseases like the flu.
Additionally, this technique could help some of those diagnosed with DiGeorge syndrome. Among other symptoms, those with the disorder are not born with a fully formed or functional thymus. There is currently no cure for this disorder, which occurs in about 1 in 4000 births.
“Our results suggest that targeting the same pathway in humans may improve thymus function and therefore boost immunity in elderly patients, or those with a suppressed immune system,” Blackburn stated in a press release. “However, before we test this in humans we need to carry out more work to make sure the process can be tightly controlled.”
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