Research Tracker›Biomarker Atlas›ME/CFS›CD26 / sCD26 (DPPIV)

CD26 / sCD26 (DPPIV) in ME/CFS

In ME/CFS (ME/CFS, CFS), the direction of change for CD26 / sCD26 (DPPIV), also described as T cell activation marker, is inconsistent across studies that used healthy controls as the reference group. The cited literature links this alteration to immune dysregulation. This entry summarises Maksoud et al. 2023. Group-level associations like this do not translate into an individual diagnostic cut-off.

↕ InconsistentImmune

Summary

Direction in ME/CFS↕ Inconsistent — reported as both higher and lower across studies, with no consistent direction
CategoryImmune
Also described asT cell activation marker
Compared againstHC (healthy controls)
Associated symptomsImmune dysregulation
Test typeBlood test (serum / plasma / whole blood)
SourceMaksoud et al. 2023 — doi:10.1186/s12916-023-02893-9
Condition atlasME/CFS Biomarker Atlas

Related Immune markers in ME/CFS

Full list: ME/CFS Biomarker Atlas.

Frequently asked questions

Is CD26 / sCD26 (DPPIV) high or low in ME/CFS?

Mixed. Some studies report higher and others lower CD26 / sCD26 (DPPIV) in ME/CFS compared with healthy controls, so no single direction is established. Source: Maksoud et al. 2023.

What symptoms is CD26 / sCD26 (DPPIV) associated with in ME/CFS?

The cited literature associates this marker with Immune dysregulation. These are population-level associations and do not mean the marker causes the symptoms.

Which test measures CD26 / sCD26 (DPPIV)?

It is measured as a blood test (serum / plasma / whole blood). Many of the cited studies used research-grade assays, so clinical availability may vary.

Is one abnormal CD26 / sCD26 (DPPIV) result diagnostic of ME/CFS?

No. No single biomarker is diagnostic of ME/CFS. CD26 / sCD26 (DPPIV) findings come from group comparisons, overlap considerably between patients and controls, and vary with study design, timing and comparison group. A result should be interpreted by a clinician alongside symptoms, history and other tests.

Cite this page

Open Source Medicine Foundation. (2026). CD26 / sCD26 (DPPIV) in ME/CFS: direction, evidence and what it means. OSMF Research Tracker. Retrieved October 7, 2026, from https://research.opensourcemed.info/biomarkers/me-cfs/cd26-scd26-dppiv.html
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Last reviewed: 2026-06-29 · Page generated from me-cfs.json · Browse: ME/CFS atlas · Biomarker Index · All marker pages

Disclaimer: This page is an educational synthesis of published, peer-reviewed research and is not medical advice. Biomarker findings vary across studies with case definitions, comparison groups, timing and assay methods. Direction of change reflects the predominant finding in the cited source and does not establish a diagnostic threshold. Discuss any test result with a qualified clinician.