IL13 is an immunoregulatory cytokine produced primarily by activated Th2 cells. IL-13 is involved in several stages of B-cell maturation and differentiation. It up-regulates CD23 and MHC class II expression, and promotes IgE isotype switching of B cells. This cytokine down-regulates macrophage activity, thereby inhibits the production of pro-inflammatory cytokines and chemokines. This cytokine is found to be critical to the pathogenesis of allergen-induced asthma but operates through mechanisms independent of IgE and eosinophils. This gene, IL3, IL5, IL4, and CSF2 form a cytokine gene cluster on chromosome 5q, with this gene particularly close to IL4.
DESCRIPTION
Interleukin-13 Human Recombinant produced in E.Coli is a single, non-glycosylated polypeptide chain containing 112 amino acids and having a molecular mass of 12 kDa.
The IL-13 is purified by proprietary chromatographic techniques.
SOURCE
Escherichia Coli.
PHYSICAL APPEARANCE
Sterile Filtered White lyophilized (freeze-dried) powder.
FORMULATION
The protein (1mg/ml) was lyophilized with 1xPBS pH-7.2 & 5% trehalose.
SOLUBILITY
It is recommended to reconstitute the lyophilized Interleukin 13 in sterile 18MΩ-cm H2O not less than 100µg/ml, which can then be further diluted to other aqueous solutions.
STABILITY
Lyophilized Interleukin-13 although stable at room temperature for 3 weeks, should be stored desiccated below -18°C. Upon reconstitution IL13 should be stored at 4°C between 2-7 days and for future use below -18°C.
For long term storage it is recommended to add a carrier protein (0.1% HSA or BSA).
Please prevent freeze-thaw cycles.
PURITY
Greater than 95% as determined by:
(a) Analysis by RP-HPLC.
(b) Analysis by SDS-PAGE.
The ED50 was determined by the dose dependent prolifiration of TF-1 cells and was found to be < 1ng/ml, corresponding to a specific activity of >1 x 106units/mg.
PROTEIN CONTENT
Protein quantitation was carried out by two independent methods:
1. UV spectroscopy at 280 nm using the absorbency value of 0.57 as the extinction coefficient for a 0.1% (1mg/ml) solution. This value is calculated by the PC GENE computer analysis program of protein sequences (IntelliGenetics).
2. Analysis by RP-HPLC, using a calibrated solution of IL-13 as a Reference Standard.
USAGE
ProSpec's products are furnished for LABORATORY RESEARCH USE ONLY. The product may not be used as drugs, agricultural or pesticidal products, food additives or household chemicals.