Recombinant Human IL-4, His 25 - Ser 153 (Accession # AAH67514) was produced in human 293 cells (HEK293).
Predicted N Terminal:
Lyophilized from sterile 20 mM MES, 200 mM NaCl, pH6.0, 10% Trehalose.
Measured by its binding ability in a functional ELISA. Immobilized Human IL-4 at 5 μg/mL (100 μL/well) can bind Human IL-4 R alpha, His Tag with a linear range of 0.01-0.1 μg/mL. The bio-activity was determined by dose-dependent stimulation of the proliferation of TF-1 cells. The ED50< 0.2 ng/mL, corresponding to a specific activity of >5000000 Unit/mg.
Human IL-4 contains no "tag", and has a calculated MW of 14.9 kDa. The reducing protein migrates as 15 and 19 kDa in SDS-PAGE due to glycosylation.
Less than 0.1 EU per μg by the LAL method.
>90% as determined by SDS-PAGE.
Samples are stable for up to twelve months from date of receipt at -70ºC.
Store it under sterile conditions at -20ºC~-70ºC. It is recommended that the protein be aliquoted for optimal storage. Avoid repeated freeze-thaw cycles.
It is recommended that sterile water be added to the vial to prepare a stock solution of 0.2 ug/ul. Centrifuge the vial at 4ºC before opening to recover the entire contents.