Related Experiment Video
Updated: Aug 8, 2026
Accurate and Simple Measurement of the Pro-inflammatory Cytokine IL-1β using a Whole Blood Stimulation Assay
Published on: March 2, 2011
Immunoassay for functional human soluble interleukin-6 receptor in plasma based on ligand/receptor interactions
F A Montero-Julian1, J Liautard, S Flavetta
1Immunotech S.A., Marseille, France.
Insights
A new enzyme-ligand immunoassay (ELIA) accurately measures soluble interleukin-6 receptor (sIL-6R) in biological fluids. This assay enables precise quantification of sIL-6R, crucial for understanding its clinical significance.
Area of Science:
- Biochemistry
- Immunology
- Molecular Biology
Background:
- Soluble cytokine receptors, including soluble interleukin-6 receptor (sIL-6R), can bind ligands and influence biological activity.
- The clinical relevance of sIL-6R levels in biological fluids requires further investigation.
- Existing methods for sIL-6R measurement may be limited.
Purpose of the Study:
- To develop and validate a novel immunometric assay for the precise measurement of soluble interleukin-6 receptor (sIL-6R).
- To quantify sIL-6R complexed with IL-6 and total sIL-6R in biological samples.
- To establish a reliable method for assessing sIL-6R levels in clinical research.
Main Methods:
- Design of an enzyme-ligand immunoassay (ELIA) utilizing anti-IL-6 and anti-IL-6R monoclonal antibodies.
- Development of a reaction scheme to measure IL-6/sIL-6R complexes.
- Preparation of a recombinant sIL-6R standard from transfected murine thymoma cells.
- Validation of the assay for precise and reproducible measurement of sIL-6R in serum and plasma.
Main Results:
- The developed ELIA accurately measures sIL-6R complexed to IL-6 in biological fluids.
- The assay can determine total sIL-6R concentrations by using excess exogenous IL-6.
- The method demonstrated precise and reproducible quantification of sIL-6R in serum and plasma samples.
- A recombinant sIL-6R standard was successfully prepared and utilized.
Conclusions:
- The developed ELIA provides a precise and reproducible method for measuring sIL-6R in biological fluids.
- This assay is valuable for investigating the clinical significance of sIL-6R.
- The assay design has broad applicability for quantifying other soluble cytokine receptors.
Abstract:
Soluble forms of most cytokine receptors, able to bind effectively to their respective ligands, have now been described. A soluble interleukin-6-binding molecule derived from the gp80 component of the multichain IL-6 receptor can be detected in biological fluids, and can act as an agonist of IL-6 activity. The clinical significance of the soluble receptor levels still remains to be explored. We took advantage of the characterization of an anti-IL-6 monoclonal antibody and of an anti-IL-6R monoclonal antibody that both bound to IL-6/IL-6R complexes to design an immunometric assay for the measurement of soluble IL-6R complexed to IL-6. This reaction scheme was designated as ELIA (enzyme-ligand immunoassay). When exogeneous IL-6 was added in excess to an sIL-6R containing sample, all sIL-6R was present in a complexed form. Thus, the reaction scheme could also be used to determine total sIL-6R concentrations. A recombinant sIL-6R standard was prepared from the supernatant of murine thymoma cells transfected with a gene coding for an extracellular portion of the IL-6 receptor. The assay permitted the precise and reproducible measurement of sIL-6R in serum or plasma. This approach is of general relevance for the determination of soluble cytokine receptors in biological fluids, provided that adequate anti-cytokine and anti-receptor antibodies are available.
