P2RX7 and graft versus host disease: Finally, our studies have revealed increased expression of murine P2rx7 and P2rx4 in GVHD tissues from Hu-PBMC-NSG mice compared to those from non-engrafted NSG mice (Cuthbertson et al., 2020) and the presence of functional murine P2X7 receptors in NSG mice (Geraghty et al., 2017), whilst both human P2RX7 and ADORA2 are detected in Hu-PBMC-NSG mice (Geraghty et al., 2019d).