CD23 is a calcium dependent transmembrane glycoprotein which is expressed in many cell types. The cytoplasmic region of the protein has two isoforms the 'a' isoform that participates in IgE-regulated endocytosis, and the 'b' isoform, which is involved in IgE-regulated phagocytosis. It has been found that there are at least four soluble forms of the CD23 protein (sCD23) all of which are produced by the activity of metallo/cysteine proteases. In addition to binding IgE, sCD23 have been shown to promote the activation and differentiation of B-cells and stimulate the release of pro-inflammatory cytokines from monocytes.
Quantity
20 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
Measured by its ability to bind in a functional ELISA. Immobilized rhCD23 at 2 µg/mL (100 µL/well) can bind human IgE with a linear range of 0.0151 µg/mL.
Weight
19.5 kDa
Description
Reconstitute at 100 µg/mL in sterile PBS
Format
Lyophilized PowderLyophilized from a 0.2 µm filtered solution in PBS
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.