Project description:This array analysis is to study the regulation of target messages’ expression in in vitro cultured murine neutrophils versus miR-223 null neutrophils. Culture media was SILAC-IMDM for MS analysis.
Project description:Radium 223 (Rad223) is a bone-seeking, alpha-particle-emitting radionuclide approved for the treatment of patients with metastatic castration resistant prostate cancer and is currently being tested in a variety of clinical trials for primary and metastatic cancers to bone. Clinical evaluation of Rad223 hematologic safety showed a significantly increased rate of neutropenia and thrombocytopenia in patients, hinting at myelosuppression as side effect. In this study we present a preclinical approach to investigate the consequences of Rad223 treatment on bone marrow biology. Rad223 accumulated in bones and induced confined radiation damage, followed by progressive replacement of the impaired areas with adipocyte infiltration, as monitored by three-dimensional multiphoton microscopy, ex vivo. Flow cytometry and single cell transcriptomic analyses on bone marrow hematopoietic populations revealed transient, non-specific Rad223-mediated cytotoxicity on resident populations, including stem, progenitor and mature leukocytes. This was paralleled by a significant decrease of white blood cells and platelets in peripheral blood, which was overcome within 40 days post-treatment. Rad223 exposure did not impair full hematopoietic reconstitution, suggesting that the bone marrow function is not permanently hampered. Our results provide a comprehensive explanation of Rad223 reversible effects on bone marrow cells and exclude long-term myelotoxicity, supporting its safety during treatment of patients at both early and late disease stages.
Project description:Analyze the transcriptome pattern of miR-155 deficient BMDC in both steady-state and inflammatory conditions, in comparison to WT counterparts.
Project description:We used a multi-omics approach combining transcriptomics, proteomics and metabolomics to study the impact of over-expression and inhibition of the microRNA miR-223, a pleiotropic regulator of metabolic-related disease, in the RAW monocyte-macrophage cell line. We analyzed the levels of proteins, mRNAs, and metabolites in order to identify genes involved in miR-223 regulation, to determine candidate disease biomarkers and potential therapeutic targets. We observed that both up- and down-regulation of miR-223 induced profound changes in the mRNA, protein and metabolite profiles in RAW cells. Microarray-based transcriptomics evidenced a change in 120 genes that were linked predominantly to histone acetylation, bone remodeling and RNA regulation. In addition, 30 out the 120 genes encoded long noncoding RNAs. The nanoLC-MS/MS revealed that 52 proteins were significantly altered when comparing scramble, pre- and anti-miR-223 treatments. Sixteen out of the mRNAs coding these proteins genes are predicted to have binding sites for miR-223. CARM-1, Ube2g2, Cactin and Ndufaf4 were confirmed to be miR-223 targets by western blotting. Analyses using Gene Ontology annotations evidenced association with cell death, splicing and stability of mRNAs, bone remodeling and cell metabolism. miR-223 alteration changed the expression of CARM-1, Ube2g2, Cactin and Ndufaf4 during osteoclastogenesis and macrophage, indicating that these genes are potential biomarkers of these processes. The most important discriminant metabolites found in the metabolomics study were found to be hydrophilic amino acids, carboxylic acids linked to metabolism and pyrimidine nucleotides, indicating that changes in miR-223 expression alter the metabolic profile of cells, and may affect their apoptotic and proliferative state.
Project description:Total bone marrow (BM) from miR-223 knockout (mir-223-/-) and wildtype (miR-223+/+) mice 21 was extracted, prestimulated for 2 days. Then, the BM cells were simultaneously cotransduced with MSCV-Hoxa9-pgk-neomycin and a MSCV-Meis1-IRES-YFP by co-cultivation with irradiated (4,000 cGy) viral producers. HoxA9-Meis1 transduced cells were sorted for YFP expression and continuously selected with neomycin (1.4 mg/ml). Processing of the pre-miRNA through Dicer1 generates a miRNA duplex, consisting of a miRNA and miRNA* strand. Despite the general view that miRNA*s have no functional role, we further investigated miRNA* species in 10 deep sequencing libraries from mouse and human tissue. Comparing miRNA/miRNA* ratios across the miRNA sequence libraries revealed that 50% of the investigated miRNA duplexes exhibit a highly dominant strand. Conversely, 10% of miRNA duplexes show a comparable expression of both strands, while the remaining 40% exhibit variable ratios across the examined libraries as exemplified by miR-223/miR-223* in murine and human cell lines. Functional analyses revealed a regulatory role for miR-223* in myeloid progenitor cells, implying an active role for both arms of the miR-223 duplex. This was further underscored by the demonstration that miR-223 and miR-223* target the IGF1R/PIK3 axis and that high miR-223* levels associate with increased overall survival in acute myeloid leukemia (AML) patients. Thus, we found a supporting role for miR-223* in differentiating myeloid cells in normal as well as the leukemic cell state. The fact that the miR-223 duplex acts through both arms extends the complexity of miRNA-directed gene regulation of this myeloid key miRNA.
Project description:In vitro generation of dendritic cells (DCs) is advantageous for overcoming the low frequency of primary DCs and the difficulty of applying isolation techniques for studying DC immunobiology. The culture of bone marrow cells with granulocyte-macrophage colony-stimulating factor (GM-CSF) has been used extensively to generate bone marrow-derived dendritic cells (BMDCs). Studies have reported the heterogeneity of cells grown in murine GM-CSF culture based on the levels of MHCII expression. Although porcine DCs are generated by this classical method, the exact characteristics of the BMDC population have not yet been defined. In this study, we discriminated GM-CSF-grown BMDCs from gnotobiotic miniature pigs according to several criteria including morphology, phenotype, gene expression pattern and function. We showed that porcine BMDCs were heterogeneous cells that differentially expressed MHCII. MHCIIhigh cells displayed more representative of DC-like morphology and phenotype, including costimulatory molecules, as well as they showed a superior T cell priming capacity as compared to MHCIIlow cell. Our data showed that the difference in MHCIIhigh and MHCIIlow cell populations involved distinct maturation states rather than the presence of different cell types. Overall, characterization of porcine BMDC cultures provides important information about this widely used cellular model.