IL-12 P40 ELISA Kit (Interleukin-12 p40)

INTENDED USE

Human IL-12 p40 ELISA kit is designed for measuring in vitro quantitative amounts of interleukin-12 p40 (IL-12 p40) present in human biological fluids, serum, tissue homogenates and plasma (EDTA, heparin, citrate). This assay has a minimum detection limit of 18.75 pg/ml.

BACKGROUND

Interleukin 12 (IL-12) which is also called by the following names cytotoxic lymphocyte maturation factor (CLMF) and natural killer cell stimulatory factor (NKSF), is a 75kDa glycoprotein heterodimer that is made up of two unequal, genetically-unrelated subunits (p35 and p40 subunits). The p40 subunit is secreted in excess of IL-12p35 and has the ability to associate with p19 (IL-23p19 or IL-23A) in order to form IL-23. There is also sequence similarity shared between the p19 subunit and IL-6 subfamily members including the p35 subunit of IL-12. However, it can only become biologically active when it combines with the p40 subunit to produce a composite cytokine IL-23, whereas P19 subunit alone has no biological activity.

IL-12 p40 subunit has total molecular weight of 34.7 kDa and is made up of 306 amino acid residues in length. There are potentially four N-linked glycosylation sites and 10 cysteine residues. In murine p40 there is approx. 70% sequence homology to human and it contains 313 amino acid residues possessing 11 conserved cysteines and three N-linked glycosylation sites. The preliminary evidence is indicating that p40 is involved in receptor binding whereas P35 is important in signal transduction.

CONTENT

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-12 p40 antibody.
• Standards: Concentrations 0, 31.25, 62.5, 125, 250, 500, 1000, 2000 pg/ml, made up from lyophilized recombinant.
• Sample/Standard Dilution Buffer.
• Biotinylated-Labelled-Antibody.
• Antibody Dilution Buffer.
• HRP-Streptavidin Conjugate (SABC).
• SABC Dilution Buffer.
• TMB Substrate.
• Wash Buffer (25x).
• Plate Sealer.
• Product Instructions.

SENSITIVITY

The minimum detection sensitivity level of interleukin-12 p40 (IL-12 p40) using this IL-12 p40 ELISA kit was approximately 18.75 pg/ml. The dynamic range for this assay is 31.2 – 2,000 pg/ml.

ASSAY CHARACTERISTICS

– Specificity: Highly specific for IL-12 p40, no cross reactivity or interference between IL-12 p40 and analogues was detected.
– Recovery: Serum (86 – 104%), EDTA Plasma (94 – 103%), Heparin Plasma (86 – 100%).
– Linearity: Serum (86 – 101%), EDTA Plasma (83 – 100%), Heparin Plasma (82 – 99%).
– Precison Intra-Assay: CV < 8%.
– Precison Inter-Assay: CV < 10%.
– Stability: Less than 10%.

REFERENCES

1. IL-12p40: an inherently agonistic cytokine. Trends Immunol. (2007) 28 (1): 33-8. Review. Cooper A.M. and Khader S.A.
2. The regulation and biological activity of interleukin 12. Leuk Lymphoma. (1998) 29 (5-6): 427-38. Review. Lee S.M., et al.
3. Does p40-targeted therapy represent a significant evolution in the management of plaque psoriasis? J Eur Acad Dermatol Venereol. (2012) 26 Suppl 5: 2-8. Review. Griffiths C.E. and Girolomoni G.
4. IL-12: the role of p40 versus p75. Scand J Immunol. (2002) 56 (1): 1-11. Review. Abdi K.

ADDITIONAL INFORMATION

• Full Name: IL-12 P40 ELISA Kit (Interleukin-12 p40)
• Reactivity: Human
• Sample Type: Tissue Homogenates, Serum, Plasma, Biological Fluids
• Sensitivity: 18.75 pg/ml

OTHER RELATED ELISA KITS

• IL-12 P70 ELISA Kit
• IL-7 ELISA Kit
• IL-4 ELISA Kit