TNF-α does not have a single universal reference range across all laboratories. Each laboratory must establish and validate its own reference interval based on the specific assay, instrumentation, and methodology it uses.
TNF-α reference ranges may vary from 1.4 – 11.9 pg/mL across laboratories dependent upon the methodology.
Because reference ranges are method-specific, results from one laboratory should not be interpreted using another laboratory’s reference range. Differences in reference intervals or flagging thresholds do not indicate that a result is invalid; rather, they reflect differences in assay methodology and laboratory validation processes. For meaningful longitudinal comparison, repeat testing should be performed on the same laboratory platform whenever possible.
Sample handling requirements are also assay-specific. For example, laboratories use a spin-and-freeze method for their TNF-α assay and testing platform. While those procedures are appropriate for that method, they should not be assumed to apply to other laboratories using different methods and instrumentation.
Vibrant’s TNF-α assay has been validated using our standardized collection process and refrigerated shipping conditions (2–8°C or 36-46°F). Based on internal validation studies, TNF-α remains stable throughout the testing process. These findings are consistent with published peer-reviewed research demonstrating that TNF-α and other cytokines can remain stable under delayed processing conditions, including both refrigerated and room-temperature storage.
References
- Jackman RP, et al. Cytokine stability in samples used for T-cell immunologic studies. Cytokine. 2011. Available at: https://pubmed.ncbi.nlm.nih.gov/21159926/
- Győrffy B, et al. Stability of cytokines under varying pre-analytical conditions. PLOS ONE. 2024. Available at: https://doi.org/10.1371/journal.pone.0311921