Summary
| Direction in Long COVID | ↑ Elevated — higher than in the comparison group |
|---|---|
| Category | Inflammatory |
| Also described as | Fibrotic cytokine |
| Compared against | HC, R (healthy controls, recovered individuals without persistent symptoms) |
| Associated symptoms | Pulmonary symptoms |
| Test type | Blood test (serum / plasma / whole blood) |
| LOINC code | 27999-4 |
| Source | Lai et al. 2023 — doi:10.3389/fmed.2023.1085988 |
| Condition atlas | Long COVID Biomarker Atlas |
Other conditions where Transforming Growth Factor-β (TGF-β) is reported
- Transforming Growth Factor-β (TGF-β) in ME/CFS — ↑ elevated vs HC
See the cross-condition hub: Transforming Growth Factor-β (TGF-β) across conditions.
Trials, interventions and tests
Commercial test availability
Transforming Growth Factor-β (TGF-β) — specialty laboratory test. Specialty send-out assay.
Links are for reference only; availability, specimen requirements and coverage vary by location.
Related Inflammatory markers in Long COVID
- Pro-inflammatory cytokines (composite) ↓
- Interleukin-8 (IL-8) ↑
- Cystatin D (CST5) ↑
- Interleukin-10 (IL-10) ↕
- CCL4 (MIP-1β) ↑
- Ferritin ↕
- Flt-1 / sVEGFR-1 ↑
- Serum Amyloid A (SAA) ↑
Full list: Long COVID Biomarker Atlas.
Frequently asked questions
Is Transforming Growth Factor-β (TGF-β) high or low in Long COVID?
Elevated. Studies summarised in the OSMF atlas report higher Transforming Growth Factor-β (TGF-β) in Long COVID than in healthy controls, recovered individuals without persistent symptoms. Source: Lai et al. 2023.
What symptoms is Transforming Growth Factor-β (TGF-β) associated with in Long COVID?
The cited literature associates this marker with Pulmonary symptoms. These are population-level associations and do not mean the marker causes the symptoms.
Which test measures Transforming Growth Factor-β (TGF-β)?
It is measured as a blood test (serum / plasma / whole blood). The standard laboratory code is LOINC 27999-4. Commercial laboratories such as ARUP Laboratories list an orderable assay.
Is one abnormal Transforming Growth Factor-β (TGF-β) result diagnostic of Long COVID?
No. No single biomarker is diagnostic of Long COVID. Transforming Growth Factor-β (TGF-β) 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.
Is Transforming Growth Factor-β (TGF-β) specific to Long COVID?
No. The same marker is also reported in ME/CFS in this atlas, so it reflects shared biology (for example inflammation or vascular stress) rather than a condition-specific signature.
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Last reviewed: 2026-06-29 · Page generated from long-covid.json · Browse: Long COVID 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.