Transcriptomic profiles of aging in purified human immune cells

Area of Science:

• Genomics
• Aging Research
• Molecular Biology

Background:

• Transcriptomic studies offer insights into human aging.
• Previous studies faced limitations due to small sample sizes and mixed cell types, hindering interpretation.

Purpose of the Study:

• To investigate age-associated gene expression patterns in purified human immune cells.
• To identify shared and cell-specific molecular signatures of aging.

Main Methods:

• Analyzed transcriptomic profiles of CD14+ monocytes from 1,264 participants (aged 55-94) in the Multi-Ethnic Study of Atherosclerosis.
• Compared monocyte data with CD4+ T cell profiles from a subset (n=423).
• Utilized false discovery rate (FDR) for statistical significance and explored methylation mediation and pulse pressure associations.

Main Results:

• Identified 2,704 age-differentially expressed genes in monocytes.
• Found six co-expressed gene networks linked to protein synthesis, oxidative phosphorylation, and autophagy, declining with age.
• Observed age-associated expression in both monocytes and CD4+ T cells for ribosomal protein synthesis genes, with cell-specific differences in other genes.

Conclusions:

• A decline in ribosomal protein synthesis gene expression with age is a shared aging pattern across CD14+ monocytes and CD4+ T cells.
• Findings underscore the importance of using purified cell types for transcriptomic aging studies.
• Further longitudinal research is needed to link identified genes and pathways to aging-related diseases.