SpecificityThe Human IL-21 ELISA Kit allows for the detection and quantification of endogenous levels of natural and/or recombinant Human IL-21 proteins within the range of 31.3 pg/ml - 2000 pg/ml.
Intended UseHuman IL21 ELISA Kit allows for the in vitro quantitative determination of IL21 , concentrations in serum, Plasma , tissue homogenates and Cell culture supernates and Other biological fluids.
StorageStore the whole ELISA kit at 4℃
Product Description specificalPrinciple of the Assay||The Human IL-21 ELISA (Enzyme-Linked Immunosorbent Assay) kit is an in vitro enzyme-linked immunosorbent assay for the quantitative measurement of Human IL-21 in Cell Culture Supernatants, Serum, Plasma. This assay employs an antibody specific for Human IL-21 coated on a 96-well plate. Standards and samples are pipetted into the wells and IL-21 present in a sample is bound to the wells by the immobilized antibody. The wells are washed and biotinylated anti-Human IL-21 antibody is added. After washing away unbound biotinylated antibody, HRP-conjugated streptavidin is pipetted to the wells. The wells are again washed, a TMB substrate solution is added to the wells and color develops in proportion to the amount of IL-21 bound. The Stop Solution changes the color from blue to yellow, and the intensity of the color is measured at 450 nm.
Background/Introduction: Interleukin-21 (IL-21) and its receptor play an important role in the regulation of the immune system. IL-21R, also called NILR (novel interleukin receptor), is a type I cytokine receptor with 4 conserved cysteine residues and an extracellular WSXWS motif. 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 native 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 found in other cytokine receptors including IL-2, IL-4, IL-7, IL-9 and IL-15. The IL21/IL21R interaction appears to play an important role in B and T cell proliferation after antigen stimulation and NK cell maturation.