IL-21, Human

IL-21 is a pleiotropic cytokine produced by CD4+ T cells in response to antigenic stimulation. Its action generally enhances antigen-specific responses of immune cells. The biological effects of IL-21 include induction of differentiation of T-cells-stimulated B-cells into plasma cells and memory B-cells, stimulation (in conjuction) with IL-4 of IgG production, and induction of apoptotic effects in naïve B-cells and stimulated B-cells in the absence of T-cell signaling. Additionally, IL-21 promotes the anti-tumor activity of CD8+ T-cells and NK cells. IL-21 exerts its effect through binding to a specific type I cytokine receptor, IL-21R, which also contains the gamma chain (gammac) found in other cytokine receptors including IL-2, IL-4, IL-7, IL-9 and IL-15. The IL-21/IL-21R interaction triggers a cascade of events which includes activation of the tyrosine kinases JAK1 and JAK3, followed by activation of the transcription factors STAT1 and STAT3.

Lyophilized from a 0.2um filtered concentrated, solution in PBS, pH 7.4.

Cytokine, Chemokines & Growth Factors

This lyophilized preparation is stable at 2-8 C, but should be kept at -20 C for long term storage, preferably desiccated. Upon reconstitution, the preparation is stable for up to one week at 2-8 C. For maximal stability, apportion the reconstituted preparation into working aliquots and store at -20 C to -70 C. Avoid repeated freeze/thaw cycles.

Proteins

USA