Secret to living longer may be the immune system’s ‘fountain of youth’

If you want to reach your 100th birthday and receive a telegram from the King, the answer may be in your immune system. 

For some over 60s with ‘immune youth’ have specialised white blood cells that restore strength and muscle mass, scientists have discovered. 

According to US researchers, who tracked more than 100 older adults, these cells known as Stem-like T cells, give people younger immune systems. 

But they also discovered those with the cells, also called stem-like memory T cells or TSL, could spread disease more easily. 

Instead, those with such cells were more likely to have autoimmunity—when the immune system mistakenly attacks healthy tissues and organs instead of defending it.

Dr Cornelia Weyand, a rheumatologist, expert in immune cell function at the Mayo Clinic in Minnesota and study co-author, said: ‘We observed that these patients have very young immune systems despite being in their 60s and 70s. 

‘But the price they pay for that is autoimmunity.’

Dr Jörg Goronzy, an immunologist at the Mayo Clinic and study co-author, added: ‘Contrary to what one may think, there are benefits to having an immune system that ages in tandem with the body.

‘We need to consider the price to pay for immune youthfulness. That price can be autoimmune disease.’

In the study, researchers tracked the 100 over 60s who attended the Mayo Clinic to receive treatment for giant cell arteritis, an autoimmune disease that affects the arteries, including the aorta. 

Writing in the journal Nature Aging, they said they found stem-like T cells in the diseased tissue of these patients. 

They also discovered the immune checkpoint inhibitors that regulate the immune system were not working properly. 

The scientists said they are now in the process of developing new diagnostic tests that will help find patients and healthy individuals who carry high numbers of immune stem cells and may be predisposed to autoimmune disease later in life. 

Last year, research suggested life expectancy across the world will rise by almost five years by 2050, with the average man forecasted to live to 76 and woman, past 80.

Global average life expectancy is forecast to increase to around 78.1 years of age in 2050, a rise of 4.5 years, The Lancet Public Health study also found.

At the time, experts said the trend was largely driven by public health measures both preventing and improving survival rates from illnesses including cardiovascular disease, nutritional diseases and maternal and neonatal infections.

Commentators also said the figures present an ‘immense opportunity’ to ‘get ahead of rising metabolic and dietary risk factors’ such as high blood pressure and BMI.

The oldest living person in the world is now believed to be Ethel Caterham, from Surrey, who was born on August 21, 1909 and is 115 years old. 

The title of the oldest person to have ever lived belongs to French woman Jeanne Louise Calment whose life spanned 122 years and 164 days. 

Ms Caterham, who died in 1997, attributed her longevity to ‘never arguing with anyone, I listen and I do what I like’.

Experts who have studied centenarians agree.

Physical activity, faith, love, companionship, and a sense of purpose make up the backbone of so-called ‘Blue Zones,’ or areas of the world where people typically live to 100 and beyond.

Maintaining an active lifestyle, even simply walking around town every day, has been shown to improve longevity.

Companionship has been shown to have a similarly positive effect on a person’s lifespan, with studies consistently showing loneliness is toxic.