Interleukin 2 (IL-2) is a pleiotropic cytokine produced primarily by mitogen- or antigen-activated T lymphocytes (1, 2). Human IL-2 (also known as T-cell growth factor) is produced by T-cells in response to antigenic or mitogenic stimulation. IL-2 is a potent lymphoid cell growth factor which exerts its biological activity primarily on T cells promoting proliferation and maturation.

Additionally, IL-2 has been found to stimulate growth and differentiation of B cells, NK cells, LAK cells, monocytes, and oligodendocytes. IL-2 is involved in treatment of cancers such as melanoma and renal cell cancer. It plays a key role in promoting the clonal expansion of antigen-specific T cells. In addition, IL-2 has also been shown to mediate multiple immune responses on a variety of cell types.

The sequence of mouse IL-2 cDNA predicts a 169 amino acid (aa) residue precursor glycoprotein containing a 20 aa residue signal peptide that is cleaved to form the mature protein (3, 4). At the amino acid sequence level, mature mouse IL-2 is approximately 60% identical to human IL-2 (1, 2, 5). Whereas human IL-2 is active on mouse cells, mouse IL-2 is species-specific and is inactive on human cells (6). The gene for IL-2 has been mapped to mouse chromosome 3 (7).

The biological effects of IL-2 are mediated by specific cell surface receptor complexes. The functional high-affinity receptor for IL-2 is composed of three distinct polypeptide chains (8, 9).

IL-2 stimulates the proliferation of thymocytes; stimulates the proliferation and differentiation of activated B cells; promotes the growth, differentiation and cytocidal activity of monocytes; induces the growth of natural killer cells and stimulates cytokine production by these cells as well as the cytolytic activity of these cells; enhances the production of lymphocyte-activated killer (LAK) cells; and induces the proliferation and differentiation of oligodendrocytes (1).

This assay employs the quantitative sandwich enzyme immunoassay technique. A monoclonal antibody specific for IL-2 has been pre-coated onto a microplate. Standards and samples are pipetted into the wells and any IL-2 present is bound by the immobilized antibody. Following incubation unbound samples are removed during a wash step, and then a detection antibody specific for IL-2 is added to the wells and binds to the combination of capture antibody-IL-2 in sample. Following a wash to remove any unbound combination, and enzyme conjugate is added to the wells. Following incubation and wash steps a substrate is added. A coloured product is formed in proportion to the amount of IL-2 present in the sample. The reaction is terminated by addition of acid and absorbance is measured at 450nm. A standard curve is prepared from seven IL-2 standard dilutions and IL-2 sample concentration determined.

Figure 1:Schematic diagram of the assay

1. Aluminium pouches with a Microwell Plate coated with monoclonal antibody to mouse IL-2 (812)

2. 2 vials mouse IL-2 Standard lyophilized, 2000 pg/ml upon reconstitution

3. 2 vials concentrated Biotin-Conjugate anti-mouse IL-2 antibody

4. 2 vials Streptavidin-HRP solution,

5. 1 bottle Standard /sample Diluent

6. 1 bottle Biotin-Conjugate antibody Diluent

7. 1 bottle Streptavidin-HRP Diluent

8. 1 bottle Wash Buffer Concentrate 20x (PBS with 1% Tween-20)

9. 1 vial Substrate Solution

10. 1 vial Stop Solution

11. 4 pieces Adhesive Films

12. package insert

NOTE: [96 Tests]

Unopened Kit：Store at 2 -8° C. Do not use past kit expiration date. opened/ReconstitutedReagents：Please refer to the datasheets for detail information.

1. Goldsmith, M.A. and W.C. Greene (1994) in The Cytokine Handbook, 2nd ed.,Thomson, A. ed., Academic Press, New York, p. 57.

2. Hatakeyama, M. and T. Taniguchi (1990) in Peptide Growth Factors and TheirReceptors I, Sporn, M.B. and A.B. Roberts eds.,Springer-Verlag, New York, p. 523.

3. Yokota, T. et al. (1985) Proc. Natl. Acd. Sci. USA 82:68.

4. Kashima, N. et al. (1985) Nature 313:401.

5. Fuse, A. et al. (1984) Nucl. Acids Res. 12:9323.

6. Thomas, R. et al. (2003)J Leukocyte Bio. 961-965

7. Bronte, V. et al. (1995) J. Immunol.5282-5292

8. Yokota, T. et al. (1985) Proc. Natl. Acad. Sci. USA 82:68.

9. Kashima, N. et al. (1985) Nature 313:401.