Human IL13 is expressed in activated T helper cells (resembling Th0, Th1, Th2), and T cells expressing CD8. The alpha chain of the IL13 receptor has weak binding activity for IL13. High affinity receptors are formed when the receptor alpha chains of IL13 and IL4 receptors are coexpressed. Different IL13 receptor structures have been shown to exist on various cell types and the IL13 receptor may share more than one component with IL4 receptor. IL13 down-modulates macrophage activity, reducing the production of pro-inflammatory cytokines and chemokines in response to IFN-gamma or bacterial lypopolysaccharides. IL13 enhances the production of the IL1 receptor antagonist IL1ra. IL13 also decreases the production of nitric oxide by activated macrophages, leading to a decrease in parasiticidal activity. IL13 induces differentiation of human monocytes, enhances survival time in culture, and also induces differentiation and proliferation and isotype switching in B cells.
Alternative Names
IL-13 ; NC30
Quantity
100 µg
Regulatory
RUO
Source
E. coli
Host
Human
Endotoxin Level
<1.0 EU/μg of recombinant protein as determined by the LAL method
Biological Activity Comment
The ED50, as determined by the dose-dependent proliferation of TF-1 cells was found to be ≤ 2.0 ng/mL
Weight
13.0 kDa
Description
A quick spin of the vial followed by reconstitution in distilled water to a concentration not less than 0.1 mg/mL. This solution can then be diluted into other buffers.
Format
Lyophilized PowderLyophilized from a 0.2 μm filtered solution in sodium phosphate and NaCl (pH 8.0)
Purity
>95% as determined by SDS-PAGE
Storage
The lyophilized protein is stable for at least one year from date of receipt at -70°C. Upon reconstitution, this cytokine can be stored in working aliquots at 2° - 8°C for one month, or at -20°C for six months, with a carrier protein without detectable loss of activity. Avoid repeated freeze/thaw cycles.