Related Experiment Video
Updated: Jun 24, 2026
09:10
Measuring Single-Cell Aging with an Imaging-based Biomarker of Chromatin and Epigenetic Aging
Published on: January 30, 2026
An Aging Clock Based on Immune Repertoire Features: COVID-19 Accelerates Aging.
Xin Gao1,2, Si-Jia Li1,3, Jin Li1
1The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Beijing Hospital, National Center of Gerontology, National Health Commission, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, People's Republic of China.
Aging Cell
|June 23, 2026
Summary
Aging reshapes T/B cell receptor repertoires, decreasing diversity and altering immune cell function. COVID-19 intensifies these age-related immune changes, impacting long-term health and recovery.
Area of Science:
- Immunology
- Gerontology
- Genomics
Background:
- Aging leads to immunosenescence, increasing vulnerability to infections.
- T/B cell receptor (TCR/BCR) repertoire changes with age are not fully understood, especially in diverse populations.
- The impact of SARS-CoV-2 on immune repertoire aging requires further investigation.
Purpose of the Study:
- To characterize T/B cell receptor repertoire remodeling during aging in Chinese individuals.
- To investigate the exacerbating effects of COVID-19 on immune repertoire aging.
- To develop and validate an immune repertoire aging clock.
Main Methods:
- High-throughput sequencing of CDR3 regions from leukocyte DNA of healthy Chinese individuals and post-COVID-19 cases.
- Analysis of TCR/BCR repertoire diversity, clonotype counts, and gene usage.
- Development of a LightGBM-based machine learning model for immune age prediction.
Main Results:
- Aging correlated with reduced TCR/BCR diversity, shorter CDR3 sequences, and altered clonotype composition, with a critical turning point around 60 years.
- Post-COVID-19 cases showed intensified repertoire aging, including altered amino acid usage and expanded pathogen-related clones.
- The developed immune aging clock validated accelerated biological aging and reduced intrinsic capacity in post-COVID-19 individuals.
Conclusions:
- Age-dependent remodeling of the immune repertoire is significant and influenced by factors like COVID-19.
- COVID-19 exacerbates immunosenescence, potentially contributing to post-viral dysfunction.
- Findings offer insights into immunosenescence and post-COVID-19 syndromes, with potential clinical applications.
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