However, the role of IFN-γ in xGVHD remains to be determined as another report showed that a P2X7 receptor antagonist reduced the serum IFN-γ concentration (~ 2-fold), without diminishing the engraftment and GVHD lethality (whereas it mildly reduced tissue damage) [123]. The gene discussed is P2RX7; the disease is graft versus host disease.