Heightened innate immunity may trigger chronic inflammation, fatigue and post-exertional malaise in ME/CFS.
Che, Xiaoyu, Ranjan, Amit, Guo, Cheng et al. · medRxiv : the preprint server for health sciences · 2025 · DOI
Quick Summary
This study found that people with ME/CFS may have an overactive immune system that responds too strongly to germs and infections. The research showed problems with how the body produces energy and manages inflammation, and these problems got worse after exercise in ME/CFS patients but not in healthy people. The findings suggest multiple biological systems are working abnormally in ME/CFS, which could help doctors develop better treatments.
Why It Matters
Understanding the biological mechanisms underlying ME/CFS—particularly how immune activation, energy metabolism, and post-exertional malaise are interconnected—is crucial for developing targeted treatments. This study provides a comprehensive molecular framework that could guide development of therapeutic interventions and validate biomarkers for diagnosis and treatment monitoring.
Observed Findings
- Exaggerated innate immune response to microbial antigens in ME/CFS patients compared to controls
- Impaired energy production through multiple metabolic pathways (citric acid cycle, fatty acid oxidation, amino acid metabolism)
- Systemic inflammation accompanied by abnormal lipid profiles and complement activation
- Disrupted tryptophan-serotonin-kynurenine pathway regulation and redox imbalance
- Worsening of metabolic and immune abnormalities following exercise in ME/CFS patients but not in healthy controls
Inferred Conclusions
- ME/CFS involves a dysregulated innate immune system that overresponds to microbial stimuli and perpetuates chronic inflammation
- Multiple interconnected metabolic abnormalities impair energy production and reinforce inflammatory processes
- Post-exertional malaise may result from exercise-induced exacerbation of underlying immune and metabolic dysfunction
- Targeted interventions addressing immune dysregulation, energy metabolism, and redox balance may be therapeutically beneficial
Remaining Questions
- Which abnormalities are primary drivers of ME/CFS pathogenesis versus secondary consequences, and can they be therapeutically targeted in sequence?
- Do specific subsets of patients have different patterns of immune and metabolic dysfunction, suggesting distinct disease subtypes requiring different treatments?
- Can these molecular markers predict which patients will respond to specific therapeutic interventions, and how do they change with treatment?
- What triggers the initial immune dysregulation, and why do some individuals recover from infection while others develop ME/CFS?
What This Study Does Not Prove
This study does not prove causation—it identifies associations between biological abnormalities and ME/CFS symptoms. It is a preprint (not yet peer-reviewed) and mechanistic in nature, so results require independent replication in larger cohorts. The study does not establish which abnormalities are primary causes versus secondary consequences of the disease.
Topics
Tags
Metadata
- DOI
- 10.1101/2025.07.23.25332049
- PMID
- 40778181
- Review status
- Editor reviewed
- Evidence level
- Early hypothesis, preprint, editorial, or weak support
- Last updated
- 7 April 2026