Hu Recom IL-33, 10 µg

Supplied by STEMCELL Technologies as a lyophilized powder, this recombinant human Interleukin-33 (UniProt O95760) belongs to the IL-1 family and acts as a pro-inflammatory mediator that binds the ST2 receptor and activates NF-κB and MAPK signaling. IL-33 is expressed by epithelial cells, smooth muscle cells, and fibroblasts in various tissues, as well as by resting basophils, mast cells, eosinophils, natural helper cells, group 2 innate lymphoid cells, dendritic cells, and activated macrophages. It contributes to allergic inflammation by driving production of IL-4, IL-5, and IL-13, and supports host defense against microbial and viral infections. In the central nervous system, endothelial cells and astrocytes release IL-33, which induces microglial proliferation and pro-inflammatory cytokine output.

The protein is produced in E. coli and lyophilized from a sterile-filtered aqueous solution containing sodium phosphate at pH 7.5. Purity is ≥ 95%, with a predicted molecular mass of 18.1 kDa. Endotoxin is ≤ 1 EU/μg protein by kinetic LAL analysis. Specific activity is ≥ 2 x 10^6 units/mg, with an EC50 ≤ 0.5 ng/mL as determined in a D10S cell proliferation assay co-stimulated with anti-CD3; a representative assay gave an EC50 of 0.1 - 0.15 ng/mL after 67 hours of culture. Mouse cross-reactivity is indicated. The lyophilized material is stored at -20°C to -80°C and remains stable for 12 months from receipt. Reconstitute in sterile water to at least 0.1 mg/mL without vortexing.

Per the safety data sheet, the material is a solid powder not classified as hazardous under GHS and is intended for research use only.