The Role of Cytokines in Traumatic Brain Injury
Abstract
1. Introduction
2. IL-1
3. IL-6
4. IL-10
5. IL-17
6. TNF-α
7. Other Cytokines
8. Pediatric TBI
9. Genetic Polymorphisms
10. Conclusions
Funding
Data Availability Statement
Conflicts of Interest
References
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| Cytokine | Main Cellular Sources | Biological Role | Clinical Relevance |
|---|---|---|---|
| IL-1β | Microglia, astrocytes, endothelial cells | Potent pro-inflammatory mediator; BBB disruption; microglial activation | Discriminates TBI vs. controls and CT+ vs. CT−; limited prognostic value for long-term outcome |
| IL-6 | Microglia, astrocytes, neurons, endothelial cells | Inflammation, BBB disruption, metabolic regulation | Strong association with injury severity, CT/MRI positivity, mortality, and functional outcome |
| IL-10 | Macrophages, T lymphocytes, microglia | Anti-inflammatory; limits immune-mediated damage | Reflects injury severity; potential tool to exclude CT lesions in selected mTBI populations |
| IL-17A | Th17 cells, γδ T cells, innate immune cells | Neutrophil recruitment; BBB disruption | Elevated in serum and effluent in TBI; possible therapeutic target |
| TNF-α | Microglia, macrophages, neurons | Dual role: pro-inflammatory and neurotrophic | Elevated in TBI and CT+ cases; inconsistent association with outcome |
| IL-8 | Microglia, astrocytes, endothelial cells | Chemotaxis, inflammation | Altered levels reported; possible association with pediatric outcomes |
| IL-9 | T cells | Immune modulation | Low levels associated with post-traumatic vasospasm |
| IL-15 | Monocytes, macrophages, endothelial cells | T-cell and NK-cell activation | Discriminates TBI severity, CT status, and functional outcome |
| Phase | Timeframe | Biomarker(s) | Kinetic Description and Duration |
|---|---|---|---|
| Hyper-Acute | <1 h | IL-1β | Rapidly upregulated mRNA and protein levels in the cortex and deep brain regions. |
| Acute | 3–24 h | IL-6, IL-10, TNF-α | IL-6: Rapid upregulation following tissue injury, staying elevated through the first 24 h. IL-10: Increased levels reported specifically on day 1. TNF-α: Significant elevation measured at a mean of 10.2 h post-injury. |
| Sub-Acute | Days 1–7 | IL-8, IL-15, IL-17A | IL-8: Baseline elevation at admission; levels remain significantly higher in non-survivors through days 5 to 7. IL-17A: Sustained elevation in both serum and effluent. |
| Delayed | Weeks | IL-9 | Characterized by a later immune modulation profile; low levels are linked to post-traumatic vasospasm which typically appears days after the initial injury. |
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Vlachodimitropoulou, L.; Lampros, M.; Alexiou, G.A.; Zikou, A.K.; Voulgaris, S.; Voulgari, P.V. The Role of Cytokines in Traumatic Brain Injury. Biomedicines 2026, 14, 879. https://doi.org/10.3390/biomedicines14040879
Vlachodimitropoulou L, Lampros M, Alexiou GA, Zikou AK, Voulgaris S, Voulgari PV. The Role of Cytokines in Traumatic Brain Injury. Biomedicines. 2026; 14(4):879. https://doi.org/10.3390/biomedicines14040879
Chicago/Turabian StyleVlachodimitropoulou, Lamprini, Marios Lampros, George A. Alexiou, Anastasia K. Zikou, Spyridon Voulgaris, and Paraskevi V. Voulgari. 2026. "The Role of Cytokines in Traumatic Brain Injury" Biomedicines 14, no. 4: 879. https://doi.org/10.3390/biomedicines14040879
APA StyleVlachodimitropoulou, L., Lampros, M., Alexiou, G. A., Zikou, A. K., Voulgaris, S., & Voulgari, P. V. (2026). The Role of Cytokines in Traumatic Brain Injury. Biomedicines, 14(4), 879. https://doi.org/10.3390/biomedicines14040879

