V‐domain immunoglobulin suppressor of T‐cell activation and programmed death receptor 1 dual checkpoint blockade enhances antitumour immunity and survival in glioblastoma

Compared with normal mice, the frequency of VISTA expression and co-expression of VISTA and PD-1 on tumour-infiltrating lymphocytes (TILs) in tumour-bearing mice was increased. Anti-VISTA monotherapy significantly up-regulated multiple immune stimulation-related pathways and moderately prolonged mouse survival time. Blocking the immune checkpoint VISTA and PD-1 significantly prolonged the survival time of mice and cured about 80% of the mice; CD8⁺ T cells played an important role in this process. In addition, we found that the expression of VISTA and PD-1 was significantly up-regulated in GBM patients by immunofluorescence, and patients with high expression of VISTA and PD-1 were associated with poor overall survival. This combination of blocking the immune checkpoint VISTA and PD-1 may achieve clinical transformation in GBM.