VISTA (D5L5T) XP^® Rabbit mAb (Alexa Fluor^® 555 Conjugate) #23245

VISTA (V-Domain Ig Suppressor of T Cell Activation) is a negative checkpoint control protein that regulates T cell activation and immune responses. VISTA, which contains a single Ig-like V-type domain, a transmembrane domain, and an intracellular domain, has sequence similarity to both the B7 and CD28 family members. Although primarily expressed by myeloid cells, VISTA is also expressed by CD4+, CD8+, and FoxP3+ T-cells. Thus, VISTA is described as both a ligand and a receptor (1-3). Blocking VISTA induces T-cell activation and proliferation, and potentiates disease severity in the EAE model (1). Furthermore, genetic deletion of VISTA in mice leads to spontaneous T-cell activation and chronic inflammation (4,5). In mouse models of cancer, neutralization of VISTA enhances T-cell proliferation and effector function and increases tumor infiltration, suggesting VISTA blockade could be an effective strategy for tumor immunotherapy (6,7).