“Hearst Magazines and Yahoo may earn commissions or revenue from certain merchandise through these links.”
As you read this story, you will learn the following:
-
Immune system function declines with age, but a team of MIT researchers may have found a way to rejuvenate it.
-
When older mice were injected with mRNA that codes for signaling pathways involved in proteins involved in immune responses, their condition improved dramatically.
-
This treatment has not yet been tested in humans, but it may one day reduce the effects of aging.
As we age, everything seems to fall apart. In addition to the almost inevitable joint creaking and random aches and pains, there are a lot of problems that not even a few aspirins can fix. Unfortunately, the immune system is one of them. Immune function declines over time due to reduced production of T cells, but there may soon be a way to reverse this decline.
T cells are produced by the thymus and promote immune system homeostasis, adapting to everything from allergens to pathogens and tumors. As thymus function declines with age, the gland shrinks and releases fewer T cells, which are prone to dysfunction and unable to respond quickly to pathogens and other threats. Now, an MIT research team led by neuroscientist Feng Zhang has found a way to reboot the immune system by reestablishing thymic signals that stimulate T cells.
“We found [our] In a recent study published in the journal, Zhang said the approach significantly improved immune responses in aging mice in both vaccination and cancer immunotherapy models, with no adverse side effects or evidence of autoimmune enhancement. nature. “These results highlight the potential of this approach to improve immune function and, more broadly, use the liver as a transient ‘factory’ to replenish factors that decline with age.”
Previous attempts to create immune fountains of youth have been unreliable, either not effective enough, clinically unfeasible, or even proven toxic. So Zhang decided to flip some genetic switches. He and his team studied old mice whose immune systems were no longer as strong as they once were. After identifying which proteins served as signaling pathways that help T cells mature and differentiate, they injected the mice with messenger RNA (mRNA) encoding the three pathways.
The mRNA targets protein synthesis in the liver, which remains high even with age. The mRNA is carried by lipid nanoparticles, and once these particles accumulate in the liver, hepatocytes (liver cells) begin producing them. This allowed Zhang’s team to essentially use the liver as a makeshift manufacturing factory for T cells. Treatment of the mice increased the number and frequency of new T cells ready to be activated, with only minor side effects after about a month of treatment.
In addition to generating T cells, this treatment also boosts the immune response to the vaccine by increasing the number of T cells that fight the antigens in the vaccine, a process that also worsens with age. Even more surprising, the treated mice had a stronger tumor response, while the tumors in untreated mice grew faster, resulting in a lower chance of survival. Nearly half of the mice injected with the mRNA completely defeated their tumors.
One problem with the treatment, however, is that continuous injections are needed to maintain improved T cell function—if the injections fail, function will return to its previous state. The therapy has not yet been tested in humans, but Zhang expects that to be the case in the future.
“[Temporarily] Repurposing the liver to express and secrete a variety of therapeutic proteins could be a versatile approach to engineering physiological processes,” he said. “By mimicking specific signaling niches within the liver […] This strategy has the potential to improve health outcomes and address a variety of human diseases and conditions. “
You may also like
