Researchers employ epigenetic clocks to unveil our true biological age, a genuine indicator of health.

A recent study investigates how the immune system contributes to comprehending and enhancing the precision of these clocks. Their pioneering method illuminates the correlation between immune cell composition and biological age, specifically examining the equilibrium between naïve and memory immune cells.

This study carries substantial implications for gaining insights into aging, implementing health interventions, and developing precise cancer treatments.

Dartmouth College

When posed the question, "How old are you?" Most individuals gauge their age based on the number of birthdays celebrated. However, scientists have introduced epigenetic clocks to gauge how 'old' the body truly is. Pioneering aging research, these clocks transcend calendar age, aiming to disclose our biological age—a genuine measure of overall health.

Despite their effectiveness, the inner workings of these clocks remain somewhat enigmatic. As highlighted in a recent New York Times article, it's akin to possessing a sophisticated device without a manual. While our bodies' internal mechanisms, particularly the immune system, play a pivotal role, the intricacies are not yet fully understood.

The far-reaching implications of these discoveries provide fresh perspectives on the aging process and potential avenues for health interventions. Dartmouth Cancer Center scientists, led by Ze Zhang, PhD, Lucas Salas, MD, MPH, PhD, and Brock Christensen, PhD, have embarked on groundbreaking research delving into the immune system's impact on epigenetic clocks. Their study, titled "Deciphering the role of immune cell composition in epigenetic age acceleration: Insights from cell-type deconvolution applied to human blood epigenetic clocks," published in Aging Cell, reveals the intricate connection between our body's biological age and the immune system.

Employing innovative tools for immune profiling, the team scrutinized immune cell profiles in relation to biological age estimates from epigenetic clocks. Notably, the balance between naïve and memory immune cells emerged as a factor influencing biological aging. Key innovations of the study include:

• Calculating Intrinsic Epigenetic Age Acceleration (IEAA) with unprecedented immune cell granularity, offering detailed insights into the cellular-level aging process.
• Providing a more direct comparison between immune cells and aging than the traditional Extrinsic Epigenetic Age Acceleration (EEAA) method.
• Adding a layer of understanding to the biological interpretation of epigenetic clocks, mapping out how various immune cell subsets contribute to epigenetic aging.
  

Zhang emphasizes that these findings deepen our understanding of the immune system's relationship with biological age at a cellular level and shed light on internal and external factors influencing aging speed.

The research's implications extend far beyond, providing new perspectives on the aging process and potential avenues for health interventions. Future studies aim to incorporate these groundbreaking findings into calculating biological age using epigenetic clocks, revolutionizing the evaluation of biological age for a more comprehensive and accurate assessment.

Upcoming research will explore the roles of different immune cells in various disease settings, particularly different types of cancer. By unraveling the complex roles of immune cells influenced by epigenetic aging, the team's work could lead to more targeted and effective cancer treatments, a deeper understanding of cancer development, and new approaches for precision cancer prevention.

Zhang envisions this trajectory transforming our understanding of disease and aging, opening possibilities in precision prevention, medicine, and targeted treatments. These steps move us closer to a future where predicting and preventing diseases, such as cancer, becomes more precise and effective, guided by enhanced knowledge of biological age and the immune system.