细胞生存和功能受到内外因素的调控，异常胞外环境在肿瘤发生、发展中起重要作用。巨噬细胞是微环境中的重要成员，参与众多生理、病理过程，其中肿瘤相关巨噬细胞（TAM）促进多数实体瘤的进展。巨噬细胞作为新型Niche参与造血干细胞调控，白血病是血液系统恶性疾病，然而白血病相关巨噬细胞鲜有研究，其性质和作用机制急待阐明。在多项国家自然科学基金课题资助下，从不同白血病裸鼠模型中发现了巨噬细胞的异常聚集和功能，体外共培养可异常活化巨噬细胞为与TAM类似又有独特表型的群体。在此基础上，本课题提出白血病相关巨噬细胞的概念，并通过小鼠急性白血病模型，深入探索白血病相关巨噬细胞的分布、表型和功能特点，以及在白血病发展中的作用机制，更完整地阐明巨噬细胞在白血病发展中的作用和意义，完善环境因素对肿瘤、白血病作用机制，具有重要的理论意义；同时，还可为进一步寻找白血病治疗的新靶点提供新线索，具有潜在的应用前景。

The survival and function of cells are strictly regulated by intrinsic and extrinsic factors. Abnormal extracellular environment take important roles on the genesis and development of malignancies. Macrophages are important members of the microenvironment, taking part in multiple physiological and pathological processes. Tumor associate macrophages (TAM) promote the malignant phenotype in most solid tumors. Macrophages, the newly suggested niche harboring hematopoietic stem cells, participate in the regulation of hematopoiesis. Leukemia is hematopoietic malignancy, whereas little has been done on leukemia associated macrophages. Their characteristics and functional mechanism need to be established. During the study for the previous NSFC grants, we found the abnormal recruitment and function of macrophages from two independent nude mice models. Furthermore, macrophages could be abnormally activated to a unique subset of cells similar to TAM in the in vitro co-culture system. In the present study, we put forward the criteria of leukemia associated macrophage. Then we study the distribution, phenotype and function of leukemia associated macrophage as well as their role in the development of leukemia by using murine acute leukemia models. This study will not only enable us to further understand the role and significance of macrophages in the development of leukemia, as well as the mechanism of environment factors on tumors and leukemia, but also provide clues for further study searching for new targets for the treatment of leukemia.