IL-2 Protein, Human (His)

IL-2 protein is mainly produced by activated CD4-positive helper T cells and plays an important role in immune response and tolerance. Binding to IL-2R induces downstream signaling through JAK1 and JAK3 phosphorylation, thereby activating various pathways, including STAT, PI3K, and MAPK. IL-2 Protein, Human (His) is the recombinant human-derived IL-2 protein, expressed by E. coli , with N-6*His labeled tag.

The cytokine interleukin-2 (IL-2), produced primarily by activated CD4-positive helper T-cells and, to a lesser extent, by activated CD8-positive T-cells and natural killer (NK) cells, plays pivotal roles in the immune response and tolerance. IL-2 binds to a receptor complex composed of either the high-affinity trimeric IL-2R (IL2RA/CD25, IL2RB/CD122, and IL2RG/CD132) or the low-affinity dimeric IL-2R (IL2RB and IL2RG). This interaction induces oligomerization and conformational changes in the IL-2R subunits, initiating downstream signaling with the phosphorylation of JAK1 and JAK3. Subsequently, JAK1 and JAK3 phosphorylate the receptor, creating a docking site for the phosphorylation of various substrates, including STAT5. This process activates multiple pathways, including STAT, phosphoinositide-3-kinase/PI3K, and mitogen-activated protein kinase/MAPK pathways. IL-2 functions as a T-cell growth factor, enhances NK-cell cytolytic activity, and promotes robust proliferation of activated B-cells, leading to increased immunoglobulin production. Furthermore, IL-2 plays a crucial role in regulating the adaptive immune system by controlling the survival and proliferation of regulatory T-cells, essential for maintaining immune tolerance. Additionally, IL-2 participates in the differentiation and homeostasis of various effector T-cell subsets, including Th1, Th2, Th17, as well as memory CD8-positive T-cells.

Measured in a cell proliferation assay using CTLL-2 mouse cytotoxic T cells. The ED₅₀ for this effect is ≤3 ng/mL.

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  Measured in a cell proliferation assay using CTLL-2 mouse cytotoxic T cells. The ED₅₀ for this effect is 0.1764 ng/mL, corresponding to a specific activity is 5.669×10⁶ units/mg.

Human

E. coli

N-6*His

P60568 (A21-T153)

3558  [NCBI]

APTSSSTKKTQLQLEHLLLDLQMILNGINNYKNPKLTRMLTFKFYMPKKATELKHLQCLEEELKPLEEVLNLAQSKNFHLRPRDLISNINVIVLELKGSETTFMCEYADETATIVEFLNRWITFCQSIISTLT

Approximately 16 kDa

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  Greater than 95% as determined by reducing SDS-PAGE.

Lyophilized powder

Lyophilized from a 0.2 μm filtered solution of PBS, 300 mM NaCl, pH 7.4 or 10 mM Sodium Citrate, pH 4.0, 8% trehalose.

<1 EU/μg, determined by LAL method.

It is not recommended to reconstitute to a concentration less than 100 μg/mL in ddH₂O. For long term storage it is recommended to add a carrier protein (0.1% BSA, 5% HSA, 10% FBS or 5% Trehalose).

Stored at -20°C for 2 years from date of receipt. After reconstitution, it is stable at 4°C for 1 week or -20°C for longer (with carrier protein). It is recommended to freeze aliquots at -20°C or -80°C for extended storage.

Room temperature in continental US; may vary elsewhere.