Systematic and Cell Type-Specific Telomere Length Changes in Subsets of Lymphocytes

Abstract EN

Telomeres, the protective DNA-protein complexes at the ends of linear chromosomes, are important for genome stability.

Leukocyte or peripheral blood mononuclear cell (PBMC) telomere length is a potential biomarker for human aging that integrates genetic, environmental, and lifestyle factors and is associated with mortality and risks for major diseases.

However, only a limited number of studies have examined longitudinal changes of telomere length and few have reported data on sorted circulating immune cells.

We examined the average telomere length (TL) in CD4+, CD8+CD28+, and CD8+CD28− T cells, B cells, and PBMCs, cross-sectionally and longitudinally, in a cohort of premenopausal women.

We report that TL changes over 18 months were correlated among these three T cell types within the same participant.

Additionally, PBMC TL change was also correlated with those of all three T cell types, and B cells.

The rate of shortening for B cells was significantly greater than for the three T cell types.

CD8+CD28− cells, despite having the shortest TL, showed significantly more rapid attrition when compared to CD8+CD28+ T cells.

These results suggest systematically coordinated, yet cell type-specific responses to factors and pathways contribute to telomere length regulation.