Hu Recom IL-4, 1000 µg

Manufactured by STEMCELL Technologies, this Human Recombinant IL-4 is supplied as a lyophilized preparation from a sterile-filtered aqueous solution containing 0.1% trifluoroacetic acid. The protein is expressed in E. coli and corresponds to UniProt accession number P05112, with a predicted molecular mass of 15.1 kDa. Alternative designations include B cell stimulating factor, BCDF, BCGF, and BSF31. The cytokine signals through a heterodimeric receptor composed of IL-4Rα and the common gamma chain, engaging JAK1/3 and recruiting STAT6 and IRS1/2, and is reported to drive immunoglobulin class switching in B cells, mast cell hyperplasia, mucus production, and the differentiation of naïve T cells into T helper type 2 (Th2) cells.

The product is supplied at a purity of ≥ 95% and an endotoxin level of ≤ 1 EU/μg protein as measured by kinetic Limulus amebocyte lysate (LAL) analysis. Biological activity is determined in a cell proliferation assay using TF-1 cells, with an EC50 of ≤ 0.25 ng/mL. Specific activity is approximately 1.4 x 10^4 IU/µg, calibrated against the human recombinant IL-4 WHO International Standard (NIBSC code: 88/656). Human IL-4 is species-specific and does not cross-react with mouse cells.

Recommended preparation is to reconstitute in sterile water to at least 0.1 mg/mL by pipetting the solution down the sides of the vial, avoiding vortexing. The product is described as stable as supplied for 12 months from the date of receipt when properly stored. According to the manufacturer's safety data sheet, the material is not classified as a hazardous substance or mixture under the Globally Harmonized System (GHS) or the 2012 OSHA Hazard Communication Standard (29 CFR 1910.1200), and is supplied for laboratory reagent / cell culture use.