Host-Microbe Multiomic Profiling Reveals Age-Dependent COVID-19 Immunopathology

Area of Science:

• Immunology
• Virology
• Gerontology

Background:

• Age is a significant risk factor for severe COVID-19, but the underlying immune mechanisms are not fully understood.
• Investigating age-related immune dysregulation is crucial for understanding COVID-19 severity and developing targeted therapies.

Approach:

• Analyzed blood and nasal samples from 1,031 hospitalized COVID-19 patients (18-96 years).
• Measured viral load, immune cell populations, inflammatory markers, and autoantibodies.
• Utilized transcriptomics, metatranscriptomics, and mass cytometry for comprehensive profiling.

Key Points:

• Older age correlated with higher SARS-CoV-2 viral load and slower viral clearance.
• Aging led to increased type I interferon and pro-inflammatory gene expression, with impaired inflammation resolution.
• Immune cell analysis revealed reduced naive T/B cells and increased monocytes and exhausted NK cells in older adults.
• Reactivation of latent viruses (HSV, CMV) was observed in the upper airways of older patients.

Conclusions:

• Aging causes significant immune dysregulation at multiple levels (transcriptional, protein, cellular) in COVID-19 patients.
• Age-dependent inflammatory imbalances and impaired immune resolution contribute to severe disease.
• Findings suggest novel therapeutic targets for mitigating age-related COVID-19 severity.