Interleukin-5 (IL-5) ELISA Kit


Interleukin-5 ELISA kit can be used for in vitro quantitative analysis of interleukin-5 (IL-5) levels in human cell culture supernatant, serum, plasma (EDTA, heparin) and urine samples. This assay has a minimum detection limit of < 2.0 pg/ml.


Interleukin-5 (IL-5) is also commonly referred to as eosinophil differentiation factor (EDF), it is a 135 amino acid polypeptide with a molecular mass of 12.5 kDa. Monomeric IL-5 has no activity and needs to form a homodimer in order for it to become active and function. One IL-5 homodimer has the ability to engage in binding to one IL-5 receptor and it has been implicated that the dimer undergoes a conformational change upon binding a receptor molecule and this change allows it to bind to a second receptor.

The amino acid sequence of mature human and mouse are approx. 75% identical, however, the human IL-5 is marginally active on mouse cells whereas mouse IL-5 is highly active on human cells. Interleukin-5 along with the chemokine eotaxin play a vital role in the coordination of the eosinophil-based inflammatory response. Even though there are many cells that contribute to inflammation, eosinophils are noted in particular because of their contribution to late phase allergic-type disorders. When they are activated within tissues, eosinophils are able to release highly basic preformed mediators (e.g. major basic protein and eosinophil peroxidase). These substances are highly toxic to parasites and can be quite damaging to the surrounding tissue functionality such as superoxide-mediated tissue destruction, vascular permeability and smooth muscle constriction.

IL-5 appears to carry out a number of functions on eosinophils which can include down modulation of Mac-1, growth and differentiation, induction of granule release, upregulation of receptors for IgA or IgG and the stimulation of lipid mediator (PAF and leukotriene C4) secretion. Finally, IL-5 has been considered as a candidate gene in the pathogenesis of asthma, since it is the main cytokine controlling eosinophil activity, eosinophils have been identified as being pivotal in the development of airway inflammation.


All reagents supplied need to be stored at 2 °C – 8 °C, unopened reagents will retain reactivity until expiration date. Do not use reagents beyond this date.

  • One 96-Well Plate: Pre-coated with anti-human IL-5 antibody.
  • Standards: Concentrations 0, 15.625, 31.25, 62.5, 125, 250, 500, 1000 pg/ml, made up from lyophilized recombinant human interleukin-5.
  • Sample/Standard Dilution Buffer.
  • Biotinylated-labelled IL-5 Antibody.
  • Antibody Dilution Buffer.
  • HRP-Streptavidin Conjugate (SABC).
  • SABC Dilution Buffer.
  • TMB Substrate.
  • Wash Buffer (25x).
  • Plate Sealer.
  • Product Instructions.


The minimum detection sensitivity level of interleukin-5 (IL-5) using this human IL-5 ELISA kit was approximately 9.375 pg/ml. The dynamic range for this assay is 15.625 – 1000 pg/ml.


– Interleukin-5 (IL-5): ELISA
– Specificity: Highly specific for IL-5, no cross reactivity or interference between IL-5 and analogues was detected.
– Recovery: Serum (85 – 100%), EDTA Plasma (87 – 100%), Heparin Plasma (85 – 103%).
– Linearity: Serum (85 – 104%), EDTA Plasma (85 – 91%), Heparin Plasma (86 – 98%).
– Precison Intra-Assay: CV < 8%.
– Precison Inter-Assay: CV < 10%.
– Stability: Less than 10%.


  1. Inhibition of interleukin-5 for the treatment of eosinophilic diseases. Discov Med. (2012) 13 (71): 305-12. Review. Corren J.
  2. Anti-interleukin-5 therapy in severe asthma. Eur Respir Rev. (2013) 22 (129): 251-7. Review. Garcia G., et al.
  3. Analysis of three human interleukin 5 structures suggests a possible receptor binding mechanism. FEBS Lett. (1998) 424 (3): 121-6. Review. Verschelde J.L., et al.
  4. Cytokine recognition by human interleukin 5 receptor. Vitam Horm. (2005) 71: 321-44. Review. Ishino T., et al.
  5. Anti-interleukin-5 antibody therapy in eosinophilic diseases. Pathobiology. (2005) 72 (6): 287-92. Review. Simon D., et al.


  • Full Name: Interleukin-5 (IL-5) ELISA Kit
  • Reactivity: Human
  • Sample Type: Serum, Biological Fluids, Plasma (Heparin, EDTA), Tissue Homogenates
  • Sensitivity: 9.375 pg/ml



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