Cytokine‐induced differentiation of hematopoietic cells into microglia‐like cells in vitro. Issue 2 (7th December 2017)

• Record Type: Journal Article
• Authors: Igarashi, Ayuko; Sakuma, Hiroshi; Hayashi, Masaharu; Noto, Daisuke; Miyake, Sachiko; Okumura, Akihisa; Shimizu, Toshiaki
• Is Part Of: Clinical & experimental neuroimmunology. Volume 9:Issue 2(2018)
• Page Start: 139
• Page End: 149
• Publication Date: 2017-12-07
• Subjects: bone marrow lineage‐negative cells -- colony‐stimulating factor 1 receptor -- interleukin‐34 -- microglia -- transforming growth factor‐β; 616.80479
• DOI: 10.1111/cen3.12429
• Languages: English
• ISSNs: 1759-1961

Abstract

Abstract: Objectives: Microglia are the immune cells of the central nervous system. Several in vitro methods have been reported to induce the formation of microglia from hematopoietic cells, using granulocyte‐macrophage colony‐stimulating factor and interleukin‐34 (IL‐34). However, the phenotype of these cells has not been fully characterized. The objective of the present study was to clarify the differential roles of colony‐stimulating factors and transforming growth factor‐β (TGF‐β) in the differentiation of hematopoietic cells to microglia‐like cells. Methods: Murine bone marrow lineage‐negative (BMLN) cells were co‐cultured with astrocytes for 1 week in the presence or absence of colony‐stimulating factors. Surface markers for microglia were examined by flow cytometry. Results: BMLN cells co‐cultured with astrocytes developed into microglia‐like cells (CD11b + CD45 lo F4/80 lo CX3CR1 hi ), whose expression pattern of surface markers was distinct from bone marrow‐derived macrophages (CD11b + CD45 hi F4/80 hi CX3CR1 lo ). Morphologically, microglia‐like cells were found to possess actively extending and retracting long branched processes. Additionally, these cells were found to proliferate significantly during differentiation and this was dependent on colony‐stimulating factor 1 receptor signaling. Macrophage colony‐stimulating factor or granulocyte‐macrophage colony‐stimulating factor induced the differentiation of BMLN cells into CD11b hi CD45 hi cells that were different from microglia. In contrast, IL‐34 induced differentiation into CD11b + CD45 lo microglia‐like cells with relatively higher CX3CR1 expression. Although TGF‐β failed to induce the formation of microglia‐like cells with process‐bearing morphology, BMLN cells cultured with both IL‐34 and TGF‐β developed into microglia‐like cells that had finely branched processes and lower F4/80 expression. Conclusions: IL‐34 and TGF‐β collectively promote the development of microglia‐like cells from hematopoietic cells. Abstract : Bone marrow lineage‐negative cells co‐cultured with astrocytes developed into microglia‐like cells (CD11b + CD45 lo F4/80 lo CX3CR1 hi ). Microglia‐like cells possessed actively extending and retracting long branched processes. IL‐34 and TGF‐beta collectively promote the development of microglia‐like cells.