Increased neutrophil apoptosis in chronic fatigue syndrome.
Kennedy, G, Spence, V, Underwood, C et al. · Journal of clinical pathology · 2004 · DOI
Quick Summary
This study found that people with ME/CFS have more dying white blood cells (neutrophils) and fewer healthy ones compared to people without the condition. The researchers also discovered that ME/CFS patients have higher levels of a chemical called TGF-beta1 that can trigger cell death. These findings suggest that ME/CFS involves measurable problems with the immune system that can be detected in a blood test.
Why It Matters
This research provides objective biological evidence that ME/CFS involves measurable immune system dysfunction, countering skepticism that the condition is purely psychological. Identifying specific immune abnormalities opens pathways for developing diagnostic tests and targeted treatments. These findings strengthen the scientific foundation for recognizing ME/CFS as a biomedical illness.
Observed Findings
ME/CFS patients had significantly higher numbers of apoptotic (dying) neutrophils compared to healthy controls
ME/CFS patients had significantly lower numbers of viable (healthy) neutrophils
Neutrophils from ME/CFS patients showed increased annexin V binding, a marker of apoptosis
Neutrophils from ME/CFS patients showed increased expression of TNF-receptor-I, a death receptor
ME/CFS patients had elevated concentrations of active TGF-beta1, an anti-inflammatory cytokine (p < 0.005)
Inferred Conclusions
ME/CFS is associated with a detectable, objective abnormality in immune cell function
The immune abnormality resembles patterns seen in patients with active viral or toxic illness
TGF-beta1 may play a role in the increased neutrophil death observed in ME/CFS patients
These immune markers could potentially serve as biomarkers for ME/CFS diagnosis and monitoring
Remaining Questions
Does the neutrophil apoptosis occur early in ME/CFS development or only in established disease, and does it change over the illness course?
What specifically triggers or maintains the elevated TGF-beta1 in ME/CFS patients?
What This Study Does Not Prove
This study does not prove that neutrophil apoptosis causes ME/CFS symptoms, only that the association exists. It cannot establish whether the immune changes are primary drivers of disease or secondary responses to infection or other factors. The relatively small sample size and single-timepoint design limit whether these findings apply to all ME/CFS patients or remain stable over time.