Recombinant Human IL-12 p40/IL12B Protein (C-His)
AG-1015-HU-HISHumanExpressed in HEK293C-His In StockSpecifications
- Species
- Human
- Expression host
- HEK293
- Tag
- C-His
- Accession
- P29460
- Amino acid range
- aa 23 – 328 (mature chain, UniProt P29460)
- Predicted MW
- 34.7 kDa (apparent 38–48 kDa due to glycosylation)
- Purity
- >95% as determined by SDS-PAGE under reducing conditions.
- Endotoxin
- Low endotoxin; every lot is tested by LAL assay, with the specification stated on the lot COA.
- Applications
- ELISA (free p40 measurement), anti-p40 antibody screening (ustekinumab), IL-12/IL-23 axis studies, receptor (IL-12Rβ1) binding assays
Bioactivity
Measured by functional ELISA. Immobilized recombinant human IL-12 p40 binds reference anti-p40 antibody (ustekinumab) with an EC50 in the range of 20–80 ng/mL.
Background
The p40 subunit (IL12B) is the shared structural component of two cytokines with opposite immunological roles: IL-12 (with p35), a potent Th1-driving and anti-angiogenic factor, and IL-23 (with p19), the maintainer of pathological Th17 responses. Monomers of p40 are secreted in excess and act as natural antagonists, so free p40 measurement is an important readout in IL-12/IL-23 axis studies. Therapeutically, ustekinumab neutralizes both IL-12 and IL-23 by binding p40 and is approved for psoriasis and Crohn's disease, while newer agents target p19 selectively. Recombinant human p40 serves anti-cytokine drug screening, free-p40 ELISA development and receptor-binding studies across this clinically central cytokine family.
Formulation & Handling
- Formulation
- Supplied in either a lyophilized powder or a ready-to-use liquid format. Buffer: PBS, pH 7.4, with 5% trehalose as cryoprotectant.
- Reconstitution
- Lyophilized: briefly centrifuge the vial before opening, reconstitute in sterile distilled water to 0.1–1.0 mg/mL, and let stand at room temperature for 10 minutes before aliquoting. Liquid: ready to use — thaw on ice and equilibrate.
- Storage
- Both lyophilized and liquid proteins are stable for 12 months at -40 °C to -80 °C. After reconstitution, aliquot and store at -40 °C to -80 °C. Avoid repeated freeze-thaw cycles.
- Shipping
- Shipped on dry ice or cold packs.
Related products
AG-1012-HU-HIS In StockAG-1013-HU-HIS In Stock