急性移植物抗宿主病(graft-versus-host disease, GVHD)是影响异基因造血干细胞移植疗效的重要因素之一，研究证实Foxp3+ Treg免疫稳态失衡是急性GVHD发生的重要环节，我们的研究提示Gal-9通过调控Foxp3+ Treg的免疫稳态参与急性GVHD发生。但Gal-9上游调控在急性GVHD发生中的机制尚未阐明。我们前期研究发现了Gal-9的新调控分子TIPE2；作为调控免疫稳态的重要分子，TIPE2在急性GVHD中的研究尚未见报道。因此，本课题创新性地从探讨TIPE2与急性GVHD发生的相关性出发，通过体外实验及体内实验，从现象观察及机制探索两个方面探究TIPE2是否通过调控Gal-9影响Foxp3+ Treg免疫稳态从而在急性GVHD发生发展中起重要作用。如获成功，有望为急性GVHD提供更安全的防治策略及治疗靶点。

Acute graft-versus-host disease (GVHD) is an important factor affecting the effect of allogeneic hematopoietic stem cell transplantation. Studies have confirmed that the imbalance of Foxp3+ Treg immune homeostasis plays an important role in the development of acute GVHD. Our study revealed that Gal-9 was involved in the pathogenesis of acute GVHD by regulating the immune homeostasis of Foxp3+ Treg. However, the exact mechanism of the upstream regulation of Gal-9 in acute GVHD has not been elucidated. Our previous studies have identified TIPE2 as a new regulatory molecule of Gal-9. Nevertheless, the role of TIPE2, an important molecular regulation of immune homeostasis, in acute GVHD has not been reported. Therefore, we intend to explore the relevance of TIPE2 with acute GVHD at first and then from two angles: in vivo and in vitro experiments and two aspects: phenomenon and mechanism, we investigate whether TIPE2 could regulate Foxp3+ Treg immune homeostasis through mediating Gal-9, resulting in its modulation on the development and progression of acute GVHD. If successful, it might provide more safe prevention strategies and new therapeutic targets for acute GVHD.