Association of T and NK Cell Phenotype With the Diagnosis of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS).
Rivas, Jose Luis, Palencia, Teresa, Fernández, Guerau et al. · Frontiers in immunology · 2018 · DOI
Quick Summary
This study compared immune system cells in the blood of people with ME/CFS to healthy people. Researchers found that ME/CFS patients had different levels of certain immune cells, particularly lower regulatory T cells and higher NKT-like cells, along with changes in natural killer (NK) cells. Using these immune cell differences, researchers could correctly identify about 70% of ME/CFS patients versus healthy controls, suggesting these immune markers might someday help doctors diagnose the condition.
Why It Matters
ME/CFS currently lacks objective diagnostic tests; diagnosis relies entirely on clinical criteria, delaying recognition and treatment. Identifying consistent immune cell abnormalities could lead to blood tests that objectively confirm ME/CFS and distinguish it from other conditions. This work supports the biological basis of ME/CFS and opens pathways for more targeted therapeutic development.
Observed Findings
ME/CFS patients had significantly lower T regulatory cells (CD4+CD25++(high)FOXP3+) compared to healthy controls
ME/CFS patients had significantly higher NKT-like cells (CD3+CD16+/-CD56+) than healthy individuals
NK cells showed reduced NKG2C expression in ME/CFS patients
NK cells showed increased CD69 and CD56bright phenotypes in ME/CFS patients
A two-marker classification model (NKG2C and regulatory T cells) correctly classified individuals as ME/CFS or healthy in 70% of cases
Inferred Conclusions
ME/CFS patients exhibit a distinct immunological profile characterized by altered T cell and NK cell subpopulations
Measurement of specific immune markers, particularly NKG2C and regulatory T cells, may help improve diagnostic accuracy for ME/CFS
Viral infections may condition these immune alterations, though direct causation is not established
These immunological differences could guide development of disease-specific therapeutic interventions
Remaining Questions
Why are regulatory T cells reduced in ME/CFS and what are the functional consequences for immune regulation?
What This Study Does Not Prove
This study does not prove these immune cell changes cause ME/CFS or that they are specific to the disease—they may occur in other conditions. The 70% diagnostic accuracy, while promising, is not sufficient for clinical practice without validation in independent cohorts. Correlation between immune markers and disease cannot establish causation or explain the mechanism underlying ME/CFS pathology.