Human IL-21 ELISA Assay

$445.00

The Human IL-21 ELISA Assay (enzyme-linked immunoassay kit) is intended for the quantitative determination of human Interleukin 21 (IL-21) concentrations in cell culture supernates, serum, and plasma. The Eagle Biosciences Human Interleukin 21 (IL-21) ELISA Assay Kit is for research use only and not to be used in diagnostic procedures.

SKU: L2131-K01 Categories: , ,

Human IL-21 ELISA Assay

The Human IL-21 ELISA Assay is For Research Use Only

Size: 1×96 wells
Sensitivity: 15 pg/mL
Dynamic Range: 31.25 – 1000 pg/ml
Incubation Time: 3.5 hours
Sample Type: Serum, Plasma, Cell Culture
Sample Size: 100 µl
Alternative Names: Interleukin 21


SAMPLE COLLECTION AND STORAGE
Cell Culture Supernates – Remove particulates by centrifugation.
Serum – Use a serum separator tube (SST) and allow samples to clot for 30 minutes before centrifugation for 15 minutes at approximately 1000 x g. Remove serum, avoid hemolysis and high blood lipid samples.
Plasma – Recommended EDTA as an anticoagulant in plasma. Centrifuge for 15 minutes at 1000 x g within 30 minutes of collection.

Assay immediately or aliquot and store samples at -20°C. Avoid repeated freeze-thaw cycles. Dilute samples at the appropriate multiple (recommended to do pre-test to determine the dilution factor).
Note: Normal human serum or plasma samples are suggested to make a 1:2 dilution.


Assay Background

Interleukin-21 (IL-21) and its receptor play an important role in the regulation of the immune system. IL-21R, also called NILR (novel interleukin receptor), is a type I cytokine receptor with 4 conserved cysteine residues and an extracellular WSXWS motif. The biological effects of IL-21 include induction of differentiation of T-cells-stimulated B-cells into plasma cells and memory B-cells, stimulation (in conjunction) with IL-4 of IgG production, and induction of apoptotic effects in native B-cells and stimulated B-cells in the absence of T-cell signaling. Additionally, IL-21 promotes the anti-tumor activity of CD8+ T-cells and NK cells. IL-21 exerts its effect through binding to a specific type I cytokine receptor, IL-21R, which also contains the gamma chain found in other cytokine receptors including IL-2, IL-4, IL-7, IL-9 and IL-15. The IL21/IL21R interaction appears to play an important role in B and T cell proliferation after antigen stimulation and NK cell maturation.


Related Products

Human IL-22 ELISA Assay Kit
Human IL-17 ELISA Assay
Human IL-32 Alpha ELISA Assay Kit

Additional Information

Assay Principle


The Eagle Biosciences Human Interleukin 21 (IL-21) ELISA Assay Kit employs the quantitative sandwich enzyme immunoassay technique. A monoclonal antibody specific for IL-21 has been pre-coated onto a microplate. Standards and samples are pipetted into the wells and any IL-21 present is bound by the immobilized antibody. Following incubation unbound samples are removed during a wash step, and then a detection antibody specific for IL-21 is added to the wells and binds to the combination of capture antibody- IL-21 in sample. Following a wash to remove any unbound combination, and enzyme conjugate is added to the wells. Following incubation and wash steps a substrate is added. A colored product is formed in proportion to the amount of IL-21 present in the sample. The reaction is terminated by addition of acid and absorbance is measured at 450nm. A standard curve is prepared from seven IL-21 standard dilutions and IL-21 sample concentration determined.

  1. Prepare all reagents and working standards as directed in the previous sections.                            
  2. Determine the number of microwell strips required to test the desired number of samples plus appropriate number of wells needed for running blanks and standards. Remove extra microwell strips from holder and store in foil bag with the desiccant provided at 2-8°C sealed tightly.
  3. Add 100 µL of Standard, control, or sample, per well. Cover with the adhesive strip provided. Incubate for 1.5 hours at 37°C.
  4. Aspirate each well and wash, repeating the process three times for a total of four washes. Wash by filling each well with Wash Buffer (350 µL) using a squirt bottle, manifold dispenser or auto-washer. Complete removal of liquid at each step is essential to good performance. After the last wash, remove any remaining Wash Buffer by aspirating or decanting. Invert the plate and blot it against clean paper towels.
  5. Add 100 µL of the working solution of Biotin-Conjugate to each well. Cover with a new adhesive strip and incubate 1 hour at 37°C.
  6. Repeat the aspiration/wash.
  7. Add 100 µL of the working solution of Streptavidin-HRP to each well. Cover with a new adhesive strip and incubate for 30 minutes at 37°C Avoid placing the plate in direct light.
  8. Repeat the aspiration/wash.
  9. Add 100 µL of Substrate Solution to each well. Incubate for 10-20 minutes at 37°C. Avoid placing the plate in direct light.
  10. Add 100 µL of Stop Solution to each well. Gently tap the plate to ensure thorough mixing.
  11. Determine the optical density of each well immediately, using a microplate reader set to 450 nm.(optionally 630nm as the reference wave length;610-650nm is acceptable) 

Documents

Product Manual


 

Please note: All documents above are for reference use only and should not be used in place of the documents included with this physical product. If digital copies are needed, please contact us.

Publications

References


1.    Parrish-Novak, J. et al. (2000) Nature 408: 57.
2.    Parrish-Novak, J. et al. (2002) J Leukoc Biol 72: 856.
3.    Konforte, D. et al. (2009) J Immunol 182: 1781.
4.    Strengell, M. et al. (2002) J Immunol 169: 3600.
5.    Davis, I.D. et al. (2007) Clin Cancer Res 13: 6926.

Product Citations