BD, 555106, BD Pharmingen™ Recombinant Rat IL-2

Preparation And Storage: Preparation And Storage This preparation contains no preservatives, thus it should be handled under aseptic conditions. Store product at -80°C prior to use or for long term storage of stock solutions. Rapidly thaw and quick-spin product prior to use. Avoid multiple freeze-thaws of product. Upon initial thawing the product should be aliquoted into polypropylene microtubes and frozen at –80°C for future use. Alternatively, the product can be diluted in sterile neutral buffer containing not less than 0.5 - 10 mg/ml carrier protein, such as human or bovine albumin, aliquoted and stored at ≤ -70°C. For in vitro biological assay use, we recommend carrier-protein concentrations of 0.5 – 1.0 mg/ml. For use as an ELISA standard we recommend carrier-protein concentrations of 5 - 10 mg/ml. Failure to add carrier protein or store at indicated temperatures may result in a loss of activity. The product should not be diluted to less than 10 μg/ml for long term storage. Carrier proteins should be pre-screened for possible effects in an appropriate experimental system. Carrier proteins may effect experimental results due to toxicity, high endotoxin levels or possible blocking activity.
Recommended Assay Procedures: Recommended Assay Procedures 1. Biological Activity Activity is tested: in a Proliferation assay using CTLL-2 indicator cells Specific activity : 0.6 - 5.0 x 10^8 Units*/mg ED50 : 20 - 150 pg/ml Observed Dose response : 100 fold * A Unit is defined as the amount of material required to stimulate a half-maximal response at cytokine saturation. Note : This application is not routinely tested at BD Biosciences. 2. ELISA Standard Recombinant rat IL-2 is useful as a quantitative standard for measuring rat IL-2 protein levels in an IL-2 specific sandwich ELISA. To obtain linear standard curves, doubling dilutions of this rat IL-2 standard from ~2,000 to 15 pg/ml should be included in each ELISA plate.