Product Specifications for Recombinant Human CD25/IL-2R alpha His-tag Protein, CF
Human embryonic kidney cell, HEK293-derived human CD25/IL-2R alpha protein Glu22-Cys213, with a C-terminal 6-His tag
>95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining.
<0.10 EU per 1 μg of the protein by the LAL method.
N-terminal sequence Analysis
Predicted Molecular Mass
35-43 kDa, under reducing conditions
Measured by its ability to inhibit the IL-2-dependent proliferation of MO7e human megakaryocytic leukemic cells. Avanzi, G. et al. (1988) Br. J. Haematol. 69:359. The ED50 for this effect is 0.15-1.2 µg/mL in the presence of 30 ng/mL of Recombinant Human IL-2 (Catalog # 202-IL)
Scientific Data Examples for Recombinant Human CD25/IL-2R alpha His-tag Protein, CF
Recombinant Human CD25/IL-2R alpha His-tag Protein Bioactivity
Recombinant Human CD25/IL-2R alpha His-tag (Catalog # 10305-RL) inhibits IL-2 dependent cell proliferation of the MO7e human megakaryocytic leukemic cell line. The ED50 for this effect is 0.15-1.2 μg/mL.
Recombinant Human CD25/IL-2R alpha His-tag Protein SDS-PAGE
2 μg/lane of Recombinant Human CD25/IL-2R alpha His-tag (Catalog # 10305-RL) was resolved with SDS-PAGE under reducing (R) and non-reducing (NR) conditions and visualized by Coomassie® Blue staining, showing bands at 35-43 kDa.
Formulation, Preparation and Storage
What does CF mean?
CF stands for Carrier Free (CF). We typically add Bovine Serum Albumin (BSA) as a carrier protein to our
Adding a carrier protein enhances protein stability, increases shelf-life, and allows the recombinant
protein to be stored at a more dilute concentration.
The carrier free version does not contain BSA.
What formulation is right for me?
In general, we advise purchasing the recombinant protein with BSA for use in cell or tissue culture, or
as an ELISA standard.
In contrast, the carrier free protein is recommended for applications, in which the presence of BSA
Lyophilized from a 0.2 μm filtered solution in PBS.
Reconstitute at 500 μg/mL in PBS.
The product is shipped at ambient temperature. Upon receipt, store it immediately at the temperature recommended below.
Stability & Storage:
Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
12 months from date of receipt, -20 to -70 °C as supplied.
1 month, 2 to 8 °C under sterile conditions after reconstitution.
3 months, -20 to -70 °C under sterile conditions after reconstitution.
Background: CD25/IL-2R alpha
IL-2 receptor alpha (IL-2R alpha), also known as CD25, is a 55 kDa type I membrane glycoprotein that belongs to the family of cytokine receptors that utilize the common gamma chain subunit (gamma c). Human IL-2R alpha cDNA encodes a 213 amino acid (aa) precursor with a 21 aa signal peptide and a 192 aa extracellular region. The ECD of Human IL-2R alpha shares a 59% amino acid sequence identity with the ECD of mouse and rat IL-2R alpha, respectively. IL‑2R alpha is primarily expressed on activated T cells and on regulatory T cells (Treg) (1-3). IL-2R beta (CD122) and gamma c (IL-2R gamma /CD132) dimerize to form a constitutively expressed intermediate affinity IL-2 receptor (4, 5). By itself, IL-2R alpha binds IL-2 with low affinity. IL-2R alpha makes no contacts with IL-2R beta or gamma c, and only minor changes are observed in the IL-2 structure in response to receptor binding. These findings support the principal role of IL-2R alpha to deliver IL-2 to the signaling complex and act as regulator of signal transduction (6, 7). A soluble form of IL‑2R alpha can be generated by proteolytic cleavage of the cell surface receptor, rendering the T cell unresponsive to IL-2 (8, 9). Increased serum levels of soluble IL‑2R alpha are found in some cancers and immune disorders (10). IL-2R alpha is required for activation induced cell death (AICD) of naive T cells, a mechanism responsible for deleting autoreactive T cell clones (11, 12). IL-2R alpha is also required for the development of CD4+CD25+ Treg which suppresses autoreactive CD4+ T cells, thereby contributing to peripheral T cell homeostasis (11-13).
Minami, Y. et al. (1993) Annu. Rev. Immunol. 11:245.
Kovanen, P.E. and Leonard, W.J. (2004) Immunol. Rev. 202:67.
Bluestone, J.A. and Tang, Q. (2005) Curr. Opin. Immunol. 17:638.
Hatakeyama, M. et al. (1989) Science 244:551.
Takeshita, T. et al. (1992) Science 257:379.
Stauber, D. et al. (2006) Proc. Natl. Acad. Sci. U. S. A. 103:2788.
Wang, X. et al. (2005) Science 310:1159.
Wagner, D.K. et al. (1986) J. Immunol. 137:592.
Schulz, O. et al. (1998) J. Exp. Med. 187:271.
Witkowska, A.M. (2005) Mediat. Inflamm. 2005:121.
Willerford, D.M. et al. (1995) Immunity 3:521.
Van Parijs, L. et al. (1997) J. Immunol. 158:3738.
Almeida, A.R.M. et al. (2002) J. Immunol. 169:4850.
Which Brands are Currently Available on bio‑techne.com? R&D Systems, Tocris Bioscience and ProteinSimple branded products are available to purchase through bio‑techne.com. ProteinSimple branded instruments are available to quote. ACD branded products will be available on bio‑techne.com in the near future. Novus Biologicals branded products are not currently available on bio‑techne.com and can be found at novusbio.com.
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