Unique protein networks in blood could offer new way to detect diseases of aging

One of the world’s largest studies of the proteins in our blood could yield a whole new understanding of how disease impacts the body as we age.

Scientists with the Age Gene/Environment Susceptibility (AGES) Reykjavik Study – a long-term study of older people in Iceland – have found that specific patterns of circulating proteins in our bloodstreams could be a new way to detect signals of health or disease.

The study by a team of scientists including Dr. Lenore Launer and Dr. Tamara Harris from the NIA Intramural Research Program was published in the journal Science. It is the first to give an overview of how these blood serum proteins connect as networks, and how these networks interact with previously mapped parts of the human genome and gene expressions on different body tissues.

The project is one of the most comprehensive analyses of secreted proteins to date, including samples from over 5,400 volunteers. The massive genetic data undertaking was made possible by collaboration between scientists at the Icelandic Heart Association, the Intramural Research Program, the Switzerland-based multinational pharmaceutical company Novartis, and SomaLogic, a Colorado-based proteomics company. The team crafted a panel of DNA aptamers – special combinations of small nucleic acid chains that bind to specific proteins – that gave them the capability to measure and identify thousands of serum proteins.

The team then scanned serum samples from a representative group of AGES study participants who ranged from age 66 to 96. They found 27 unique protein expression networks or modules, many of which were found to be tied to past or present bouts with -- or even future likelihood of -- chronic diseases of aging such as dementia, diabetes, hardening of the arteries, metabolic syndrome and heart disease.

The scientists with the AGES study see the serum proteins as potential new types of easy-to-sample, low-cost biomarkers. They hope further study of data from these unique protein networks can someday help us better understand how common diseases of aging leave their mark in the body and progress over time, opening up potential new therapeutic avenues.

Reference: Emilsson V et al. Co-regulatory networks of human serum proteins link genetics to disease. Science. 2018 Aug 2. pii: eaaq1327. doi: 10.1126/science.aaq1327.