Targeting cell surface VISTA expression on allospecific naïve T cells promotes tolerance.

The success of allogeneic hematopoietic stem cell transplantation (allo-HSCT) can be limited by graft-versus-host disease (GVHD). T-cell activation is a key factor in GVHD progression. Costimulatory signals can be counterbalanced by co-inhibitory signals such as the checkpoint molecule VISTA (V-domain Ig-containing suppressor of T-cell activation)/PD-1H that restrains activation and maintains donor T-cell quiescence.