Stimulation of granulopoiesis by transforming growth factor beta: synergy with granulocyte/macrophage-colony-stimulating factor.

Transforming growth factor-beta (TGF-beta) has potent antiproliferative effects on human hematopoietic progenitor cells. We report here that TGF-beta 1 and -beta 2 also exert bimodal dose-dependent stimulation of granulocyte-macrophage colony-stimulating factor (CSF) and granulocyte- CSF-induced day 7 granulocyte-macrophage colony-forming units. This increase in colony formation was restricted to low doses (0.01 to 1.0 ng/mL) of TGF-beta 1 and was due to increased granulopoiesis, showing that TGF-beta can affect the differentiation as well as the proliferation of hematopoietic progenitors. Furthermore, TGF-beta 3 was found to be a more potent inhibitor of hematopoietic progenitor cells than TGF-beta 1 and -beta 2. In contrast to the bidirectional proliferative effects of TGF-beta 1 and -beta 2, the effects of TGF- beta 3 on human hematopoiesis were only inhibitory, showing for the first time that TGF-beta isoforms differ not only in potencies but also with regard to the nature of the response they elicit.

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Vascular Smooth Muscle Cell–Derived Transforming Growth Factor-β Promotes Maturation of Activated, Neointima Lesion–Like Macrophages

Arteriosclerosis Thrombosis and Vascular Biology ◽

10.1161/atvbaha.114.303214 ◽

2014 ◽

Vol 34 (4) ◽

pp. 877-886 ◽

Cited By ~ 22

Author(s):

Allison Ostriker ◽

Henrick N. Horita ◽

Joanna Poczobutt ◽

Mary C.M. Weiser-Evans ◽

Raphael A. Nemenoff

Keyword(s):

Smooth Muscle ◽

Growth Factor ◽

Macrophage Activation ◽

Transforming Growth Factor ◽

Conditioned Media ◽

Colony Stimulating Factor ◽

Macrophage Colony Stimulating Factor ◽

Macrophage Colony ◽

Stimulating Factor

Objective— To define the contribution of vascular smooth muscle cell (SMC)–derived factors to macrophage phenotypic modulation in the setting of vascular injury. Approach and Results— By flow cytometry, macrophages (M4) were the predominant myeloid cell type recruited to wire-injured femoral arteries, in mouse, compared with neutrophils or eosinophils. Recruited macrophages from injured vessels exhibited a distinct expression profile relative to circulating mononuclear cells (peripheral blood monocytes; increased: interleukin-6, interleukin-10, interleukin-12b, CC chemokine receptor [CCR]3, CCR7, tumor necrosis factor-α, inducible nitric oxide synthase, arginase 1; decreased: interleukin-12a, matrix metalloproteinase [MMP]9). This phenotype was recapitulated in vitro by maturing rat bone marrow cells in the presence of macrophage-colony stimulating factor and 20% conditioned media from cultured rat SMC (sMφ) compared with maturation in macrophage-colony stimulating factor alone (M0). Recombinant transforming growth factor (TGF)-β1 recapitulated the effect of SMC conditioned media. Macrophage maturation studies performed in the presence of a pan-TGF-β neutralizing antibody, a TGF-β receptor inhibitor, or conditioned media from TGF-β–depleted SMCs confirmed that the SMC-derived factor responsible for macrophage activation was TGF-β. Finally, the effect of SMC-mediated macrophage activation on SMC biology was assessed. SMCs cocultured with sMφ exhibited increased rates of proliferation relative to SMCs cultured alone or with M0 macrophages. Conclusions— SMC-derived TGF-β modulates the phenotype of maturing macrophages in vitro, recapitulating the phenotype found in vascular lesions in vivo. SMC-modulated macrophages induce SMC activation to a greater extent than control macrophages.

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