Exploration of Immunology

Table 1. Cytokine pattern, oxidative stress, and specific immune cells dysfunction in FMS patients

Category	Biomarkers/Cells	Observed changes in FMS	Functional/Clinical implications
Pro-inflammatory cytokines	IL-6, IL-8, TNF-α	↑ levels	Pain amplification, fatigue, mood disturbances
Anti-inflammatory cytokines	IL-10	↓ levels	Sustained pro-inflammatory state
Oxidative stress	Malondialdehyde, protein carbonyls	↑ levels	Correlate with symptom severity
Antioxidant defense	Glutathione, superoxide dismutase	↓ activity	Increased oxidative damage
Immune system cells	T-reg cells	↓ cell count and function	Failure to suppress immune hyperactivation
Immune system cells	NK cells	↓ activity	Compromised immune surveillance

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Most studies cited used blood or serum samples and cytokine assays, such as ELISA, to quantify cytokine concentrations in FMS patients. Biomarkers such as malondialdehyde were assessed in plasma using spectrophotometric assays. NK cell activity was commonly evaluated using flow cytometry-based cytotoxicity assays. T-reg cell counts were determined through immunophenotyping. FMS: fibromyalgia syndrome; T-reg cells: regulatory T cells; NK: natural killer; ↑: increased; ↓: decreased

Declarations

Acknowledgments

The authors wish to express their gratitude to colleagues of the Rheumatology Department and Clinical Psychology of the University of Verona for their valuable insights, constructive feedback, and critical discussions that greatly enhanced the quality of this review. Their expertise and thoughtful suggestions contributed to the refinement of the manuscript. Any remaining errors or omissions are solely the responsibility of the authors.

Author contributions

MN: Conceptualization, Investigation, Writing—original draft, Writing—review & editing. VS and GV: Conceptualization, Writing—review & editing. LG and EP: Validation, Writing—review & editing, Supervision. AM, SC, and GDB: Supervision, Writing—review & editing. LP: Investigation. ES: Writing—original draft. All authors read and approved the submitted version.

Conflicts of interest

Giustino Varrassi, who is the Editorial Board Member and a Guest Editor of Exploration of Immunology, had no involvement in the decision-making or the review process of this manuscript. The other authors declare that they have no conflicts of interest.

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