Fig. 3

The clustering results of immune status for healthy individuals. a PCA visualization of the clustering results; b The proportions of each immune status group across different age periods (the young: 20–40; the middle-aged: 41–60; the old: > 60); c The number of individuals belonging to each immune status group as a function of age; d The proportion of individuals belonging to each immune status group as a function of age (*P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001)