Aging, imbalanced inflammation and viral infection.
1Department of Internal Medicine, Yale University School of Medicine, New Haven, CT, USA. daniel.goldstein@yale.edu
Virulence
|December 24, 2010
Summary
Older adults may be more vulnerable to viral infections due to exaggerated immune responses, specifically elevated Interleukin-17 (IL-17) levels, leading to severe outcomes. This research suggests new anti-inflammatory treatments could improve infection recovery in the elderly.
Area of Science:
- Immunology
- Gerontology
- Virology
Background:
- Aging is associated with increased susceptibility to viral and secondary bacterial infections.
- Current understanding suggests this is due to declining immune function in older individuals.
- However, emerging evidence points towards dysregulated immune responses in aging.
Purpose of the Study:
- To investigate the role of immune response exaggeration in age-related susceptibility to viral infections.
- To identify specific inflammatory mediators and immune cells involved in this process.
- To explore potential therapeutic strategies targeting immune dysregulation in elderly patients.
Main Methods:
- Comparative analysis of immune responses in aged and young mice infected with herpes virus.
- Quantification of serum inflammatory mediator levels, particularly Interleukin-17 (IL-17).
- Assessment of natural killer T-cell (NKT-cell) contributions and interferon-alpha (IFN-α) responses by plasmacytoid dendritic cells (pDCs).
Main Results:
- Aged mice exhibited significantly higher serum levels of the inflammatory mediator IL-17 compared to younger mice post-herpes viral infection.
- Elevated IL-17 responses in aged mice were linked to lethal immune pathology.
- Natural killer T-cells (NKT-cells) were identified as key contributors to heightened IL-17 production in aged individuals, synergizing with impaired viral clearance due to defective IFN-α responses by pDCs.
Conclusions:
- Contrary to prevailing theories, exaggerated immune responses, specifically elevated IL-17, contribute to severe viral infections in older adults.
- Age-related immune pathology during viral infection involves a complex interplay between heightened IL-17 and impaired viral clearance mechanisms.
- Targeting imbalanced inflammation with novel anti-inflammatory drugs may offer a promising therapeutic approach to improve outcomes for elderly individuals facing viral infections.
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