TACR1 and acute graft versus host disease: A loss of corneal endothelial cells but an upregulation of neurokinin-1 receptor (NK1R) was observed in an acute GVHD murine model, suggesting that ocular GVHD affects the corneal endothelium, inducing the cell number reduction, which is associated with increased expression of the proinflammatory marker NK1R (46).