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 expressed in human 293 cells is a glycosylated monomer with an apparent molecular mass of 17 to 40 kDa.
<1 EU/µg of recombinant protein as determined by the LAL method
Biological Activity Comment
The EC(50) as determined by the dose-dependent stimulation of the proliferation of human TF-1 cells (human erythroleukemic indicator cell line).was found to be ≤ 2 ng/mL.
Weight
17 to 40 kDa, monomer,glycosylated
Description
A quick spin of the vial followed by reconstitution in sterile 1xPBS.
Format
Lyophilized Powder1x 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. Avoid repeated freeze/thaw cycles.