Project description:Conditioned medium (CM) from bone marrow derived macrophages untreated or treated with LPS was collected and filtered through a 0.22-μm filter. The filtered CM was sequentially fractionated with 50-kDa and 100-kDa Amicon filters. The 50–100 kDa fraction of CM was analyzed by mass spectrometry.
Project description:In vivo pathways of natural retinoid metabolism and elimination have not been well characterized in primary myeloid cells, even though retinoids and retinoid receptors have been strongly implicated in regulating myeloid maturation. Using a UAS-GFP reporter transgene, and retrovirally expressed Gal4-RARA in primary mouse bone marrow cells, we identified two distinct enzymatic pathways utilized by mouse myeloid cells ex vivo to synthesize RARA ligands from free vitamin A metabolites (retinyl acetate, retinol, and retinal). Bulk Kit+ bone marrow progenitor cells utilize diethylaminobenzaldehyde (DEAB)-sensitive enzymes, whereas bone marrow-derived macrophages use DEAB-insensitive enzymes to synthesize natural RARA-activating retinoids (all-trans retinoic acid). Bone marrow-derived macrophages do not express the DEAB-sensitive enzymes Aldh1a1, Aldh1a2, or Aldh1a3, but instead express Aldh3b1, which we found is capable of DEAB-insensitive synthesis of all trans-retinoic acid. However, under steady-state and stimulated conditions in vivo, diverse bone marrow cells and peritoneal macrophages showed no evidence of intracellular RARA-activating retinoids despite expression of these enzymes and a vitamin A sufficient diet, suggesting that the enzymatic conversion of retinal is not the rate limiting step in the synthesis of intracellular RARA-activating retinoids in myeloid bone marrow cells and that that RARA remains in an un-liganded configuration during adult hematopoiesis. In order to identify additional enzymes that might contribute to DEAB-insensitive retinoid synthesis in bone marrow-derived macrophages, we compared gene expression in Kit+ progenitor cells vs bone marrow macrophages by Affymetrix array profiling. We analyzed 3 biological samples each of mouse bone marrow-derived macrophages and Kit+ progenitor cells
Project description:In vivo pathways of natural retinoid metabolism and elimination have not been well characterized in primary myeloid cells, even though retinoids and retinoid receptors have been strongly implicated in regulating myeloid maturation. Using a UAS-GFP reporter transgene, and retrovirally expressed Gal4-RARA in primary mouse bone marrow cells, we identified two distinct enzymatic pathways utilized by mouse myeloid cells ex vivo to synthesize RARA ligands from free vitamin A metabolites (retinyl acetate, retinol, and retinal). Bulk Kit+ bone marrow progenitor cells utilize diethylaminobenzaldehyde (DEAB)-sensitive enzymes, whereas bone marrow-derived macrophages use DEAB-insensitive enzymes to synthesize natural RARA-activating retinoids (all-trans retinoic acid). Bone marrow-derived macrophages do not express the DEAB-sensitive enzymes Aldh1a1, Aldh1a2, or Aldh1a3, but instead express Aldh3b1, which we found is capable of DEAB-insensitive synthesis of all trans-retinoic acid. However, under steady-state and stimulated conditions in vivo, diverse bone marrow cells and peritoneal macrophages showed no evidence of intracellular RARA-activating retinoids despite expression of these enzymes and a vitamin A sufficient diet, suggesting that the enzymatic conversion of retinal is not the rate limiting step in the synthesis of intracellular RARA-activating retinoids in myeloid bone marrow cells and that that RARA remains in an un-liganded configuration during adult hematopoiesis. In order to identify additional enzymes that might contribute to DEAB-insensitive retinoid synthesis in bone marrow-derived macrophages, we compared gene expression in Kit+ progenitor cells vs bone marrow macrophages by Affymetrix array profiling.
Project description:Glioblastoma multiforme (GBM) presents a formidable clinical challenge due to its complex microenvironment. Here, we introduce lipid droplet (LD)-loaded macrophages, or tumor-associated foam cells (TAFs), as a previously unidentified immune cell population in GBM. Through extensive analyses of patient tumors, together with in vitro and in vivo investigations, we reveal that TAFs exhibit distinct pro-tumorigenic characteristics related to hypoxia, mesenchymal transition, angiogenesis, and impaired phagocytosis. Moreover, TAF presence correlates with worse patient outcome. Our mechanistic investigations demonstrate that TAF formation is facilitated by lipid cargo from extracellular vesicles released by GBM cells. Importantly, we demonstrate that targeting key enzymes involved in LD formation, such as DGAT1 or ACSL, effectively disrupts TAF functionality. This study establishes TAFs as a prominent immune cell entity in GBM and provides valuable insights into their interplay within the microenvironment. Disruptin
Project description:To identify factors that could explain why mice transplanted with Vim deficient bone marrow display decreased atherosclerosis despite increased inflammation, we performed global gene expression profiling of bone-marrow derived macrophages from vimentin-deficient or wild-type littermates on C57BL/6 background. We elucidated the role of vimentin in atherogenic low-density receptorâ deficient mice after bone marrow transplantation from vimentin-deficient mice.
Project description:Macrophages were derived from the bone-marrow of 3 x fl/+ Dicer LysCre +/- (wild-type) and 3 x fl/fl Dicer LysCre +/- mice and stimulated with IL-4 (50ng/mL) for 72h. Total RNA was isolated and analyzed by gene array. In this experiment, we derived Dicer deficient bone-marrow macrophages using Dicer fl/+ LysM-Cre by Dicer fl/+ crossed mice to obtain Dicer fl/fl LysM-cre progeny (and Dicer deficient macrophages). Next, we studied the effects of IL-4 stimulation in macrophage with a deficiency in Dicer/microRNAs.