Bcakground

Interleukin-2 (IL-2) is an O-glycosylated four α-helix bundle cytokine that has potent stimulatory activity for antigen-activated T cells. It is expressed by CD4⁺ and CD8⁺ T cells, γδ T cells, B cells, dendritic cells, and eosinophils (1–3). Mature mouse IL-2 shares 56% and 73% amino acid (aa) sequence identity with human and rat IL-2, respectively. It shows strain-specific heterogeneity in an N-terminal region that contains a poly-glutamine stretch (4). Mouse and human IL-2 exhibit cross-species activity (5).

The receptor for IL-2 consists of three subunits that are present on the cell surface in varying preformed complexes (6–8). The 55 kDa IL-2Rα is specific for IL-2 and binds with low affinity. The 75 kDa IL-2Rβ, which is also a component of the IL-15 receptor, binds IL-2 with intermediate affinity. The 64 kDa common γ chain (γc/IL-2Rγ), which is shared with the receptors for IL-4, -7, -9, -15, and -21, does not independently interact with IL-2. Upon ligand binding, signal transduction is performed by both IL-2Rβ and γc.

IL-2 is best known for its autocrine and paracrine activity on T cells. It drives resting T cells to proliferate and induces IL-2 and IL-2Rα synthesis (1, 2). It contributes to T cell homeostasis by promoting the Fas-induced death of naïve CD4⁺ T cells but not activated CD4⁺ memory lymphocytes (9). IL-2 plays a central role in the expansion and maintenance of regulatory T cells, although it inhibits the development of Th17-polarized cells (10–12). Thus, IL-2 may be a key cytokine in the natural suppression of autoimmunity (13, 14).

Reference

1. Ma, A. et al. (2006) Annu. Rev. Immunol. 24:657.

2. Gaffen, S.L. and K.D. Liu (2004) Cytokine 28:109.

3. Kashima, N. et al. (1985) Nature 313:402.

4. Matesanz, F. et al. (1993) Immunogenetics 38:300.

5. Mosmann, T.R. et al. (1987) J. Immunol. 138:1813.

6. Liparoto, S.F. et al. (2002) Biochemistry 41:2543.

7. Wang, X. et al. (2005) Science 310:1159.

8. Bodnar, A. et al. (2008) Immunol. Lett. 116:117.

9. Jaleco, S. et al. (2003) J. Immunol. 171:61.

10. Malek, T.R. (2003) J. Leukoc. Biol. 74:961.

11. Laurence, A. et al. (2007) Immunity 26:371.

12. Kryczek, I. et al. (2007) J. Immunol. 178:6730.

13. Afzali, B. et al. (2007) Clin. Exp. Immunol. 148:32.

14. Fehervari, Z. et al. (2006) Trends Immunol. 27:109.

Specifications

Synonyms	Aldesleukin; IL2; IL-2; IL-2lymphokine; interleukin 2; interleukin-2;T-cell growth factor; TCGF
Accession #	P04351
Source	Human embryonic kidney cell, HEK293-derived mouse IL-2 protein
Source	Ala21-Gln169
Predicted Moleucular weight	17.2kDa

Components and Storage

Formulation	Solution protein
	Dissolved in sterile PBS buffer
	This solution can be diluted into other aqueous buffers. Centrifuge the vial prior to opening
Storage and Stability	Avoid repeated freeze-thaw cycles
	It is recommended that the protein be aliquoted for optimal storage
	12 months from date of receipt, -20 to -70 °C as supplied
Shipping	Shipping with dry ice

Quality

Purity	> 95%, determined by SDS-PAGE
Endotoxin Level	<0.010 EU per 1 ug of the protein by the LAL method
Activity	Measured in a cell proliferation assay using CTLL-2 mouse cytotoxic T cells
Activity	The EC50 for this effect is 0.01-0.1 ng/mL

SDS-PAGE

Bioactivity

Documents

Mouse IL2