The Healthy Human Global Project - Hong Kong : a community-based cross-sectional study of a healthy Asian population

Immune responses are highly variable from one individual to another, with this variability determined by factors such as age, sex, genetics and environment, which also affect physical and mental well-being. Systems immunology studies have been applied to human cohort studies to better understand these effects, but most are performed in Western populations of mostly European ancestry, neglecting the vast majority of human global diversity. To overcome this limitation, we established the Healthy Human Global Project Hong Kong (HHGP-HK) cohort to allow the study of immune variability in a healthy Asian population. Taking inspiration from the established French Milieu Interieur study we adapted inclusion and exclusion criteria to identify healthy donors, and to facilitate cross comparison between the two cohorts we collected similar demographic, medical and lifestyle information. To study the effects of age and sex, donors were stratified for both ranging from 20-79 years. We report here significant age and sex effects on multiple clinical laboratory measures, many of which were consistently observed in the Milieu Interieur cohort. C-reactive protein and liver enzymes were two exceptions perhaps reflecting different environmental effects between the two cohorts. We applied biological aging, physiological, and mental health scores to our cohort which highlights the need to develop and adapt such scores for application to populations of non-European descent. We also included wearable fitness trackers from which we observed significant age and sex differences for sleep, physical activity, and heart rate variability. This unique cohort will enable the better understanding of factors that determine immune variability within Asian populations.