The Mouse IL-21 Antibody is a SULFO-TAG conjugated detection antibody for IL-21. It is the same detection antibody that is in the V-PLEX Mouse IL-21 Assay. Detection antibody is supplied as a 50X concentrated solution. Mouse IL-21 (CVID11) is expressed by activated NK cells and TH17 cells. It stimulates proliferation of B-cells and up-regulates NK cells. IL-21 is a co-stimulator of multiple T-cell biological actions including activation, proliferation and polarization. IL-21 signals through a heterodimeric receptor to the JAK/STAT pathway.