IL3 is produced mainly by T cells following cell activation by antigens and mitogens, but also by keratinocytes, natural killer cells, mast cells, endothelial cells, and monocytes. The analysis of bacterial- derived recombinant IL3 shows that glycosylation is not required for activity. IL3 sequences are evolutionarily less well conserved with human and murine IL3 sharing approximately 29% homology (at the protein level) and murine and rat IL3 sharing approximately 54% homology. IL3 receptors are expressed on macrophages, mast cells, eosinophils, megakaryocytes, basophils, bone marrow progenitor cells and various myeloid leukemia cells. Binding of IL3 to its receptor causes specific phosphorylation of a 150 kDa membrane glycoprotein. Recombinant human IL3 is a non-glycosylated globular protein.
<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 Human TF-1 cells was found less than 0.5 ng/mL
Weight
15.0 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 Phosphate Buffer and NaCl (pH 6.3)
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.