异基因造血干细胞移植是目前根治急性白血病的有效手段，但移植后白血病复发和巨细胞病毒（CMV）感染等并发症严重影响预后，这两种并发症之间的关系迄今不明。近年来研究和我们Meta分析结果提示，移植后早期CMV感染可以降低白血病的复发率，介导抗白血病效应(GVL)。结合我们前期研究，移植后CMV感染可以影响T细胞亚群的分化和重建，这可能与感染后级联式炎症网络反应有关。本研究拟通过分析移植患者CMV感染后IL-12p40/p70、IFN-γ、IL-18、IP-10水平，检测体外感染人外周血单个核细胞和鼠脾脏细胞后细胞因子及FOXO1磷酸化情况，探索IL-12/IFN-γ炎症轴在调控T-bet/Eomes平衡，诱导Tc、NK和γδT等免疫细胞分化中的作用；同时在白血病小鼠骨髓移植模型中，应用活体动物成像技术验证病毒的GVL效应。这一研究将为破解CMV感染介导GVL的细胞与分子免疫学机制提供新的证据。

Allogeneic hematopoietic stem cell transplantation (Allo-HSCT) is a potentially lifesaving treatment for patients with acute leukemia. Leukemia relapse and cytomegalovirus (CMV) infection remain challenging problems in the HSCT procedure, causing significant morbidity and mortality. Recent studies and our meta-analysis show that early CMV reactivation post HSCT decreases the risk of leukemia relapse, possibly by graft-versus-leukemia effect(GVL). CMV infection can affect the differentiaton and reconstitution of T cells after HSCT in our previous report, which may be related to a cascade of inflammatory network. We will detect the level of IL-12p40/p70,IFN-γ,IL-18 and IP-10 in peripheral blood of transplant recipients with CMV reactivation, and in human peripheral mononuclear blood cells and spleen cells of mice infected with CMV. We will explore the role of IL-12/IFN-γ axis in regulating T-bet/Eomes balance and differentiation of Tc, NK, and γδT cells. Fanally, we will also validate GVL in an EL4 leukemia allo-HSCT model of mice using in vivo imaging technology. This study will provide new evidence for the cellular and molecular immunology mechanism of GVL induced by CMV infection.