Purity
>95%, by SDS-PAGE under reducing conditions and visualized by silver stain
Endotoxin Level
<0.01 EU per 1 μg of the protein by the LAL method.
Activity
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 ED 50 for this effect is 0.35-1.4 µg/mL in the presence of 30 ng/mL of recombinant human IL-2.
Source
Chinese Hamster Ovary cell line, CHO-derived
Rat CD25/IL-2 R alpha
(Glu22-Gln235)
Accession # P26897IEGRMDP Mouse IgG2a
(Glu98-Lys330)N-terminus C-terminus Accession #
N-terminal Sequence
AnalysisGlu22
Structure / Form
Disulfide-linked homodimer
Predicted Molecular Mass
51.6 kDa (monomer)
SDS-PAGE
70-85 kDa, reducing conditions
5156-RM |
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Formulation Lyophilized from a 0.2 μm filtered solution in PBS. | ||
Reconstitution Reconstitute at 500 μg/mL in sterile PBS. | ||
Shipping 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.
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Background: CD25/IL-2 R alpha
IL-2 receptor alpha (IL-2 R 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). IL-2 R alpha is primarily expressed on activated T cells and on regulatory T cells (Treg) (1-3). The rat IL-2 R alpha cDNA encodes a 267 amino acid (aa) precursor that includes a 21 aa signal peptide, a 214 aa extracellular domain (ECD) with two Sushi domains, a 21 aa transmembrane segment, and an 11 aa cytoplasmic domain (4). Within the ECD, rat IL-2 R alpha shares 58% and 81% aa sequence identity with human and mouse IL-2 R alpha, respectively. It shares approximately 15% aa sequence identity with IL-4, -7, -9, -15, and -21 receptor subunits that also complex with gamma c. IL-2 R beta (CD122) and gamma c (IL-2 R gamma /CD132) dimerize to form a constitutively expressed intermediate affinity IL-2 receptor (5, 6). By itself, IL-2 R alpha binds IL-2 with low affinity. It associates with IL-2 R beta and gamma c to generate a ternary high affinity IL-2 receptor complex (7). A soluble form of IL-2 R 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-2 R alpha are found in some cancers and immune disorders (10). IL-2 R 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-2 R alpha is also required for the development of CD4+CD25+ Treg which suppress autoreactive CD4+ T cells, thereby contributing to peripheral T cell homeostasis (11-13).
References:
Minami, Y. et al. (1993) Annu. Rev. Immunol. 11:245.
Kovanen, P.E. and W.J. Leonard (2004) Immunol. Rev. 202:67.
Bluestone, J.A. and Q. Tang (2005) Curr. Opin. Immunol. 17:638.
Page, T.H. and M.J. Dallman (1991) Eur. J. Immunol. 21:2133.
Hatakeyama, M. et al. (1989) Science 244:551.
Takeshita, T. et al. (1992) Science 257:379.
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) Mediators 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.
Long Name:
Interleukin 2 Receptor alpha
Entrez Gene IDs:
3559 (Human); 16184 (Mouse); 25704 (Rat); 403870 (Canine)
Alternate Names:
CD25 antigen; CD25; IDDM10; IL-2 R alpha; IL-2 receptor subunit alpha; IL2R alpha; IL-2R subunit alpha; IL2R; IL2RA; IL-2Ra; IL-2-RA; IL2-RA; interleukin 2 receptor, alpha; interleukin-2 receptor subunit alpha; p55; TAC antigen; TCGFR
