Human IL21 (Interleukin 21) Microsample ELISA Kit

The test principle applied in this kit is Sandwich enzyme immunoassay. The microtiter plate provided in this kit has been pre-coated with an antibody specific to Human IL21. Standards or samples are added to the appropriate microtiter plate wells then with a biotin-conjugated antibody specific to Human IL21. Next, Avidin conjugated to Horseradish Peroxidase (HRP) is added to each microplate well and incubated. After TMB substrate solution is added, only those wells that contain Human IL21, biotin-conjugated antibody and enzyme-conjugated Avidin will exhibit a change in color. The enzyme-substrate reaction is terminated by the addition of sulphuric acid solution and the color change is measured spectrophotometrically at a wavelength of 450nm ± 10nm. The concentration of Human IL21 in the samples is then determined by comparing the OD of the samples to the standard curve.Detection Range: 31.3-2000 pg/mL. Sensitivity: 17.4 pg/mL. Assay Type: Sandwich. Standard: 2000 pg/mL. Sample Type: sserum, plasma, tissue homogenates, cell lysates, cell culture supernates and other biological fluids. Assay duration: 3.5h. Protein Function: Cytokine with immunoregulatory activity. May promote the transition between innate and adaptive immunity. Induces the production of IgG(1) and IgG(3) in B-cells (By similarity). Implicated in the generation and maintenance of T follicular helper (Tfh) cells and the formation of germinal-centers. Together with IL6, control the early generation of Tfh cells and are critical for an effective antibody response to acute viral infection (By similarity). May play a role in proliferation and maturation of natural killer (NK) cells in synergy with IL15. May regulate proliferation of mature B- and T-cells in response to activating stimuli. In synergy with IL15 and IL18 stimulates interferon gamma production in T-cells and NK cells (PubMed:11081504, PubMed:15178704). During T-cell mediated immune response may inhibit dendritic cells (DC) activation and maturation (By similarity) [The Uniprot Consortium]