Deep sequencing of BCR heavy chain repertoires in myalgic encephalomyelitis/chronic fatigue syndrome.
Ryback, Audrey A, Cowan, Graeme J M · Frontiers in immunology · 2025 · DOI
Quick Summary
This study examined immune system cells called B cells in people with ME/CFS to see if the disease might be caused by chronic infections or autoimmune problems. Researchers compared blood samples from 25 patients with mild/moderate ME/CFS, 36 with severe ME/CFS, healthy people, and people with multiple sclerosis. They found that ME/CFS patients' B cells did not show the typical patterns expected if chronic infection or autoimmunity were the main cause, though they did notice a difference in the balance of certain antibody types in milder cases.
Why It Matters
Understanding whether ME/CFS is driven by chronic infections or autoimmunity has major implications for treatment strategies. This study's direct examination of B-cell responses provides evidence against these leading hypotheses, potentially redirecting research toward other disease mechanisms. The observed IgM/IgG skewing suggests new biological leads that could improve diagnostic approaches and therapeutic understanding.
Observed Findings
- ME/CFS patients showed no increased B-cell clonality or differential somatic hypermutation compared to healthy controls and MS patients.
- IGHV3-30 gene usage was increased in mild/moderate ME/CFS patients, partially replicating a prior finding.
- No evidence of ongoing adaptive immune responses was detected in IGHV3-30 repertoires from patients with increased usage.
- A skewed ratio of IgM to IgG antibodies was observed in patients with mild/moderate ME/CFS.
- No detectable B-cell repertoire signatures consistent with chronic infection or autoimmunity were found in ME/CFS patients overall.
Inferred Conclusions
- ME/CFS does not display B-cell immune signatures typical of chronic infection or classical autoimmunity.
- The IgM/IgG ratio skewing in mild/moderate disease represents a potential new biological marker requiring further investigation.
- Previously reported IGHV3-30 increases in ME/CFS may represent population variation rather than evidence of ongoing adaptive immune responses.
- Alternative disease mechanisms beyond B-cell-mediated infection or autoimmunity should be prioritized in ME/CFS research.
Remaining Questions
- What is the functional significance of the altered IgM/IgG ratio in mild/moderate ME/CFS, and does it persist longitudinally?
- Are T-cell repertoires, innate immune cells, or cytokine dysregulation better explanations for ME/CFS pathogenesis than B-cell responses?
- Why does the IGHV3-30 increase appear in some populations but lack evidence of active immune responses?
- Do tissue-resident B cells or B cells in cerebrospinal fluid show different patterns than peripheral blood B cells in ME/CFS patients?
What This Study Does Not Prove
This study does not prove ME/CFS is not infectious or autoimmune in all cases—B-cell repertoire patterns alone cannot fully exclude these mechanisms, and findings in blood may not reflect immune responses in tissues. The lack of detected repertoire signatures does not rule out other immune abnormalities (T cells, innate immunity, cytokine dysregulation). The cross-sectional design cannot establish causation or temporal relationships between immune changes and disease.
Topics
Tags
Metadata
- DOI
- 10.3389/fimmu.2025.1489312
- PMID
- 40034707
- Review status
- Machine draft
- Evidence level
- Single-study or moderate support from human research
- Last updated
- 7 April 2026