VISTA, also known as B7-H5, PD-1H, platelet receptor Gi24, Dies1, and SISP1, is a transmembrane glycoprotein that promotes both MT1-MMP expression and the MT1-MMP mediated activation of MMP-2. VISTA supports the differentiation of embryonic stem cells (ESC) and enhances BMP-4 induced signaling in ESC but is also downregulated following BMP-4 exposure. It binds to BMP-4 directly and also associates with the type I BMP receptor Activin RIB/ALK-4. VISTA is expressed on the surface of naïve CD4+ T cells, regulatory T cells, and adipocytes. It is upregulated in vivo on activated monocytes and dendritic cells. VISTA inhibits CD4+ and CD8+ T cell proliferation and their production of IL-2 and IFN-gamma. Its expression on tumor cells attenuates the anti-tumor immune response and enables more rapid tumor progression. In contrast, VISTA limits disease progression in the autoimmune disease model EAE.