CytoStim causes activation of T cells by binding to the T cell receptor (TCR) and cross-linking it to a major histocompatibility complex molecule of an antigen–presenting cell. CytoStim is an antibody–based reagent that acts similarly to a superantigen but independently of certain Vβ domains of the TCR. Upon incubation with CytoStim, CD4
+ and CD8
+ cells start to secrete effector cytokines or up-regulate activation markers on their cell surface within a few hours. CytoStim is suitable for rapid stimulation of CD4
+ and CD8
+ T cells in fresh PBMCs, whole blood, or other leukocyte-containing single-cell suspensions from tissues. It can be used instead of SEB as a positive control in antigen-specific T cell stimulation assays or intracellular cytokine staining experiments to detect cytokine or activation marker expression.
