IL-6
Interleukin-6 is the cytokine at the centre of the acute-phase response, chronic inflammation and cytokine release syndrome. Quantify it, detect it or stimulate with it: every IL-6 format for human, mouse, rat and veterinary species, with datasheets and protocols included.
Start from what your experiment has to answer: how much IL-6 is in the sample, where it is expressed, or what happens when cells are exposed to it.
Sandwich ELISA for serum, plasma, cell-culture supernatant and tissue lysate. Pre-coated 96-well plate, standards and detection reagents included; results in under 4 hours.
Browse IL-6 ELISA kits → DetectPolyclonal and monoclonal antibodies validated for western blot, IHC, ICC and flow cytometry, plus neutralising clones for blocking IL-6 signalling in culture.
Browse IL-6 antibodies → StimulateBioactive recombinant IL-6 for cell stimulation, STAT3 phosphorylation assays, ELISA standards and binding studies. Carrier-free options available.
Browse IL-6 proteins →Interleukin-6 is a pleiotropic cytokine secreted by monocytes, macrophages, T cells, fibroblasts, endothelial cells and adipocytes in response to pathogen-associated signals, IL-1 and TNF-α. It binds the membrane-bound IL-6 receptor (IL-6R, CD126) and recruits two gp130 molecules, triggering JAK1/JAK2 phosphorylation and STAT3 activation.
Because IL-6R is restricted to hepatocytes and leukocytes, most tissues respond through trans-signalling: IL-6 bound to soluble IL-6R (sIL-6R) activates gp130 on cells that lack the receptor. This mechanism underlies much of the pro-inflammatory activity of IL-6 and is the rationale for sgp130-based therapeutics.
In the liver IL-6 drives synthesis of C-reactive protein, serum amyloid A, fibrinogen and hepcidin. In the immune system it promotes B-cell differentiation into antibody-secreting cells, supports Th17 development together with TGF-β, and inhibits regulatory T-cell induction.
IL-6 is poorly conserved between species (human and mouse IL-6 share about 42% amino-acid identity), so a species-matched assay is essential. We stock kits and proteins for the models most used in inflammation, infection and veterinary research.
| Species | Available formats | Typical samples |
|---|---|---|
| Human | ELISA kits (standard & high-sensitivity), sIL-6R ELISA, antibodies, recombinant protein | Serum, plasma, cell-culture supernatant, CSF, synovial fluid |
| Mouse | ELISA kits, IL-6R ELISA, antibodies, recombinant protein | Serum, plasma, BAL fluid, tissue homogenate, supernatant |
| Rat | ELISA kits, recombinant protein | Serum, plasma, tissue homogenate |
| Bovine, porcine, ovine, equine, canine, goat, chicken, rabbit | ELISA kits, recombinant protein | Serum, plasma, milk, supernatant |
Need a species or matrix you don't see here? Ask technical support — many kits have validation data for additional sample types on request.
Healthy human serum IL-6 is usually below 5–10 pg/mL. Choose a high-sensitivity kit for baseline or exercise studies, and a standard-range kit for sepsis, CRS or stimulated cultures where levels reach ng/mL.
IL-6 is stable for a few hours at room temperature but degrades with repeated freeze–thaw. Separate serum or plasma within 30 minutes, aliquot, and store at −80 °C; avoid more than two freeze–thaw cycles.
Total IL-6 ELISA measures free and sIL-6R-bound cytokine. If trans-signalling is the question, pair the IL-6 kit with an sIL-6R or sgp130 ELISA and report the ratio.
Most healthy adults fall below 5–10 pg/mL, rising with age, obesity and smoking. Values above 50–100 pg/mL are typical of active infection or inflammatory disease, and can exceed 1,000 pg/mL in cytokine release syndrome or septic shock.
No. Human and mouse IL-6 share only ~42% sequence identity and the capture/detection antibody pairs are species-specific. Use the matching species kit; for humanised mouse models, run both assays.
Both work. EDTA plasma gives slightly lower and more consistent values than serum because clotting can release IL-6 from platelets and leukocytes. Whichever you choose, keep it consistent across the study.
Yes. Bioactive recombinant IL-6 is routinely used at 1–100 ng/mL to induce STAT3 phosphorylation in hepatoma, myeloma and T-cell lines. Check the datasheet for the ED50 of the specific lot.
The IL-6 ELISA quantifies the cytokine itself; the sIL-6R ELISA measures the soluble receptor that enables trans-signalling. They answer different questions and are often run together in inflammation studies.