Product Information

Protein sequence	A DNA sequence encoding IL-15 (P40933) and IL-15RA (Q13261) was expressed with the C-terminal fused Fc region of human IgG1
Expression Host	HEK293 cells
QC Testing Purity	> 95 % as determined by SDS-PAGE
Activity	The ED₅₀ as determined by the dose-dependent stimulation of the proliferation of CTLL-2 cells was found to be 0.2~3 ng/mL. The specific activity of recombinant human IL-15 is ≥ 5 × 10⁶ IU/mg, which is calibrated by the human IL-15 WHO International Standard (NIBSC code: 95/554)
Endotoxin Level	< 0.01 EU per μg of the protein as determined by the LAL method
Molecular Mass	The recombinant human IL-15 predicts a molecular mass of 12.8 kD and 33 kD
Formulation	Lyophilized from sterile PBS, pH 7.4. Normally 6 % mannitol are added as protectants before lyophilization
Stability & Storage	24 months at 2 °C to 8 °C in lyophilized state. 6 months at -20 °C under sterile conditions after reconstitution. 12 months at -80 °C under sterile conditions after reconstitution. Recommend to aliquot the protein into smaller quantities after reconstituting with water for injection, normal saline or PBS. Avoid repeated freeze-thaw cycles.

Background

The protein encoded by IL-15 gene is a cytokine that regulates T cell and natural killer cell activation and proliferation. IL-15 and IL-2 share many biological activities. They are found to bind common hematopoietin receptor subunits, and may compete for the same receptor, and thus negatively regulate each other's activity. The number of CD8+ memory cells is shown to be controlled by a balance between IL-15 and IL-2. IL-15 induces the activation of JAK kinases, as well as the phosphorylation and activation of transcription activators STAT3, STAT5, and STAT6. Studies of the mouse counterpart suggested that IL-15 may increase the expression of apoptosis inhibitor BCL2L1/BCL-x(L), possibly through the transcription activation activity of STAT6, and thus prevent apoptosis. Alternatively spliced transcript variants of this gene have been reported.

References

X. Zhu, W.D. Marcus, W. Xu, H.I. Lee, K. Han, J.O. Egan, J.L. Yovandich, P.R. Rhode, H.C. Wong, Novel human interleukin-15 agonists, J Immunol 183(6) (2009): 3598-3607.
M. Chirifu, C. Hayashi, T. Nakamura, S. Toma, T. Shuto, H. Kai, Y. Yamagata, S.J. Davis, S. Ikemizu, Crystal structure of the IL-15-IL-15Ralpha complex, a cytokine-receptor unit presented in trans, NatImmunol 8(9) (2007)：1001-1007.

Document

Recombinant Human IL-15 Protein

Recombinant Human IL-15 Protein_SDS

Recombinant Human IL-15 Protein-T&L