Aging of immune system: immune signature from peripheral blood lymphocyte subsets in 1068 healthy adults

TLDR

Aging is a major risk factor for neurodegenerative, cardiovascular, and cancer conditions and is linked to impairments in genomic stability and immune control pathways. The study aims to identify a phenotypic signature of circulating immune cells associated with aging to develop biomarkers of immune senescence that could improve vaccine responses and therapeutic strategies. The authors conducted a cross‑sectional analysis of 1,068 healthy Chinese adults aged 18–80, profiling peripheral blood lymphocyte subsets to characterize age‑related changes. They found that aging is associated with a decline in naive CD4⁺ and CD8⁺ T cells, an expansion of memory T cells, loss of CD28 expression, and altered CD38/HLA‑DR expression, while NK and B cell counts remain stable, and they provide Chinese reference ranges for peripheral lymphocyte subsets.

Abstract

Aging is a major risk factor for several conditions including neurodegenerative, cardiovascular diseases and cancer. Functional impairments in cellular pathways controlling genomic stability, and immune control have been identified. Biomarker of immune senescence is needed to improve vaccine response and to develop therapy to improve immune control. To identify phenotypic signature of circulating immune cells with aging, we enrolled 1068 Chinese healthy volunteers ranging from 18 to 80 years old. The decreased naïve CD4+ and CD8+ T cells, increased memory CD4+ or CD8+ T cells, loss of CD28 expression on T cells and reverse trend of CD38 and HLA-DR, were significant for aging of immune system. Conversely, the absolute counts and percentage of NK cells and CD19+B cells maintained stable in aging individuals. The Chinese reference ranges of absolute counts and percentage of peripheral lymphocyte in this study might be useful for future clinical evaluation.