IL27 and graft versus host disease: Ayasoufi K proved that IL‐27 neutralization or receptor deficiency delayed CD8+ T cell recovery after murine anti‐thymocyte globulin (mATG) treatment in heart allotransplantation mouse model,8 and blocking IL‐27 pathway prevented from graft‐versus‐host disease (GVHD) occurrence through promoting Treg cell reconstitution and stabilizing Foxp3 expression,9 suggested IL‐27 with pro‐inflammation and allorejection accelerating effects.