Buck Institute boffins, with colleagues at Stanford University, claim to have created the first “actionable clock” which can figure out when you’re likely to croak it, and even help prolong your life: the inflammatory clock of ageing, or iAge.
“Standard immune metrics which can be used to identify individuals most at risk for developing single or even multiple chronic diseases of ageing have been sorely lacking,” claimed David Furman, PhD, who serves as both an associate professor at the Buck Institute for Research on Ageing and as director of the 1001 Immunomes Project at Stanford University – an effort to use machine learning to discover the secrets of ageing using the blood of 1,001 individuals. Furman continued:
Bringing biology to our completely unbiased approach allowed us to identify a number of metrics, including a small immune protein which is involved in age-related systemic chronic inflammation and cardiac ageing. We now have means of detecting dysfunction and a pathway to intervention before full-blown pathology occurs.
Key to the team’s discovery: CXCL9, a soluble chemokine which is called into action when lymphocytes are required at the site of an infection.
“But in this case, we showed that CXCL9 upregulates multiple genes implicated in inflammation and is involved in cellular senescence, vascular ageing, and adverse cardiac remodelling,” explained first author Nazish Sayed, MD, PhD.
In other words: it’s possible to determine the age of a person’s immune system, which provides a means of measuring their health – and how far along they are in their inexorable march to the grave.
“On average, centenarians have an immune age that is 40 years younger than what is considered ‘normal’,” Furman said of those participating the study. “We have one outlier, a super-healthy 105 year-old man (who lives in Italy) who has the immune system of a 25 year old.”
Furman further claimed that a person’s iAge can be used to track their risk of developing a range of chronic diseases, including age-related frailty.
“Using iAge it’s possible to predict seven years in advance who is going to become frail,” he said of the study’s findings. “That leaves us lots of room for interventions.”
“It’s becoming clear that we have to pay more attention to the immune system with age, given that almost every age-related malady has inflammation as part of its aetiology,” Furman concluded.
The discovery may also have implications in slowing down ageing itself, in a manner somewhat less drastic than that proposed by scientists earlier this month: Sayed, assistant professor of vascular surgery at Stanford Medicine, pointed out that silencing CXCL9 was found to reverse the loss of function in ageing endothelial cells – the material lining blood and lymphatic vessels – in both humans and mice.
The team’s paper has been published under closed-access terms in the journal Nature Aging. ®