Immune Markers Characterize Exceptional Health in Aging

Exceptional cognitive and physical function in old age leaves a tell-tale immunologic fingerprint, and conversely – older adults who have mild impairments bear a distinct immunologic pattern as well. Abbe N. de Vallejo, from the University of Pittsburgh School of Medicine (Pennsylvania, USA), and colleagues collected blood samples from 140 subjects, ages 78 to 94 years, enrolled in the Cardiovascular Health Study for nearly two decades. The team also gathered information about the participants' health and function, medical history and hospitalizations, and self-rated health, and assessed their cognitive and physical function using standard tests. Those participants who were most physically and cognitively resilient had a dominant pattern of stimulatory NK receptors on the T-cell surface, and these unusual T-cells could be activated directly through these NK receptors independently of the conventional ones. The functionally resilient elders also were observed to have a distinct profile of blood proteins called cytokines that reflect an immune-enhancing environment.  Conversely, the researchers showed mild health impairment had a dominant pattern of inhibitory NK receptors on their T-cells, and they have a cytokine profile indicating a pro-inflammatory environment.  Writing that: “Collectively, these data demonstrate the importance of immunological parameters in distinguishing between health phenotypes of older adults,” the team submits that their findings suggest “novel immunopathway(s) that could be exploited to improve immunity in old age.”