Fig. 6: Systemic administration of anti-VISTA reduces lung tumor burden and promotes anti-tumor immunity.

A Schematic of KLN205-Pten^null WT or Mlst8-KO cells inoculation and treatment schedule with IgG control and anti-VISTA (seven doses, blue arrows). B Representative images of the lungs harvested from IgG control or anti-VISTA treated KLN205-Pten^null WT tumor bearing mice after 25 days of tumor cell implantation. Scale bar: 100 μm. Lung weight indicating tumor burden from IgG Control and anti-VISTA. C Immunohistochemistry showing increased tumor cell apoptosis (Cleaved Caspase3) and increased CD8⁺ T cells in anti-VISTA treated animals. Scale bar: 20 μm. Flow cytometry analysis of CD25⁺ (D), GZMB⁺ (E) on CD8⁺ from anti-VISTA treated mice. F, G Flow cytometry was further performed on IgG and anti-VISTA treated animals for IFNγ⁺ and TNF-α⁺ on CD4⁺ T cells. Each dot on the quantification represents one mouse (n = 7–16 per group). p-values were determined by two-tailed unpaired Student t test. H Schematic of cytotoxic co-culture assay and quantification, where JH716-OVA-sgControl cells were co-cultured with CD8⁺ T cells in tumor conditioned medium (TCM) and in the presence of IgG control, or α-VISTA, or α-PSGL-1 (n = 3). p values were determined by two-way ANOVA with Tukey’s post hoc. *p < 0.05, **p < 0.01, ***p < 0.001, FC fold change.