Stromal cells secrete exosomes carrying specific molecular signature involved in the support of Hematopoietic Stem and Progenitor Cells
ABSTRACT: Purpose: The study focused on the RNA content of supportive (AFT024) and non supportive (BFC012) stromal lines and their respective exosomes to analyze the molecular complexity of the Hematopoietic Stem and Progenitor Cell niche Methods: All the samples from small RNA (SR) and polyA-RNA libraries were sequenced using 1×50 bp single reads high-throughput sequencing (RNA-Seq) in single lane on Illumina HiSeq 2500. The sequence reads that passed quality filters were analyzed at the transcript isoform level with TopHat followed by Cufflinks and by Fisher's test for polyA-RNA, or with bowtie and parse tools for smallRNA (galaxy server https://lbcd41.snv.jussieu.fr/). Results: Using an optimized data analysis workflow, we mapped about 30 million sequence reads per sample to the mouse genome (build mm10). We focused on differentially expressed transcripts between i) exosomes from supportive and non supportive stromal cells and ii) exosomes and their respective cells.Using a subtractive strategy, we identified 324 mRNAs and 23 miRNAs specific to the exosomes of the supportive stromal line AFT024. We used gene ontology annotation to study the biological functions associated to these specific gene sets. Transcripts involved in negative regulation of apoptosis were found enriched in AFT exosomes. Conclusions: Our RNA seq analysis combined with biological assays reveal that exosomes serve as an important and novel mediator for the HSPC supporting capacity of stromal cells. This unprecedented effort to resolve the molecular complexity of the HSPC-targeted exosomes, provide new candidat genes of the HSPC support and may help designing innovative stromal-free culture conditions to deliver specific molecules to HSPCs. Fetal liver derived stromal lines and their corresponding secreted exosomes were sequenced using Illumina HiSeq2500 technology (Fasteris, CH). Due to low amount of exosomal RNAs, several RNA extraction were pooled and split to perform 2 technical sequencing replicates that were merged during bionformatic analyses.
Project description:One of the long-standing goals in the field has been to establish a culture system that would allow maintenance of HSC properties ex vivo. In the absence of such system, the ability to model human hematopoiesis in vitro has been limited, and there has been little progress in the expansion of human HSCs for clinical application. To that end, we defined a mesenchymal stem cell co-culture system based on a monoclonal OP9 stromal cell line (OP9M2), for expansion of clonally multipotent human HSPCs that were protected from apoptosis and immediate differentiation, and retained the HSPC phenotype. To identify the supportive mechanisms, we performed a genome-wide gene expression analysis of OP9M2 stromal cells and compared the expression to a non-supportive stomal line (BFC012). This co-culture system provides a new, well-defined platform for studying mechanisms involved in HSC-niche interactions and protection of critical HSC properties ex vivo. To determine the cellular identity and the supportive mechanism of the OP9M2 cells, we compared the OP9M2 cells with non-supportive BFC012 stromal cells using Affymetrix mouse microarrays.
Project description:We recently showed that exosomes from primary AML cells and cell lines have potent regulatory capacity and we hypothesized that leukemia cell exosome trafficking might account for the suppression of residual hematopoietic stem and progenitor cells (HSPC) in the leukemic niche. Here we studied Molm-14 cells in in vitro experiments using purified exosomes under carefully calibrated low-oxygen conditions. This approach revealed the active regulation of stromal- and hematopoietic progenitor cell function. Systematic analysis of AML exosomes identified a panel of differentially enriched hypoxia-responsive miRNAs, including miR-210, -155, and -146a. We cultured cells under normoxic and hypoxic conditions. Exosomes were released from the parental cells and captured. Total RNA was isolated from both exosomes and cells. Please note that the sample numbers (in the titles) do differ from pair identification (i.e. pair ID) as the pair is only in reference to the paired-t test and parental vs. released pairs.
Project description:Tumor infiltrating neutrophils (TAN) have been shown to exert both pro- and anti-tumoral activities and their recruitment and polarization are triggered by tumor-derived signals. Resident mesenchymal stromal cells (MSC) could contribute to tumor-supportive cell niche and have been shown to display tumor-specific transcriptomic, phenotypic, and functional features compared to normal tissue. In our study, we investigate whether these two cell subsets establish a bidirectional crosstalk in the context of B-cell lymphoma. We used microarrays to explore how neutrophils could trigger the polarization of tumor-supportive stromal cells. Gene expression analysis were performed on stromal cells (MSC) derived from bone marrow (BM) or tonsil (Resto) of healthy donors. These BM-MSC (n=3) or Resto (n=3) were primed or not with neutrophils for 1 day to induce stromal modification.
Project description:Polycomb Repressive Complex 2 (PRC2) has been shown to play a key role in hematopoietic stem and progenitor cell (HSPC) function. Analyses of mouse mutants harboring deletions of core components have implicated PRC2 in fine-tuning multiple pathways that instruct HSPC behavior, yet how PRC2 is targeted to specific genomic loci within HSPCs remains unknown. Here we use shRNA-mediated knockdown to survey the function of known PRC2 accessory factors in HSPCs by testing the competitive reconstitution capacity of transduced murine fetal liver cells. We find that similar to the phenotype observed upon depletion of core subunit Suz12, depleting Jarid2 enhances the competitive transplantation capacity of both fetal and adult, mouse and human HSPCs. Gene expression profiling revealed common Suz12 and Jarid2 target genes that are enriched for the H3K27me3 mark established by PRC2. These data implicate Jarid2 as an important component of PRC2 that has a central role in coordinating HSPC function. RNA-seq of jarid knockdown, suz knockdown and control from HSPC in 16 week old mice.
Project description:Epithelial (CD31-CD45-EpCAM+) and stromal (CD31-CD45-EpCAM-) lung cells were derived by FACS from ShhCre;Ezh2fl/fl and control ShhCre;Ezh2fl/+ mouse embryos at day E16.5 (3 biological replicates per genotype-tissue combination). Total RNA extracted from the samples was subjected to NGS library preparation using TruSeq Stranded Total RNA with Ribo-Zero (Illumina). Completed libraries from different samples were sequenced on HiSeq 2000 TruSeq with SBS Kit v3 - HS reagents (Illumina) as 100 bp single end reads at the Australian Genome Research Facility. RNA-seq gene expression profiles from Ezh2 deficient and control lung epithelial and stromal cell populations at day E16.5 (3 replicates per genotype-tissue combination).
Project description:we examine the genes expression after activation of mitoflash. The MEF were expressed with CypD or treated with paraquat and mastoparan. RNA was harvested using Trizol reagent. Illumina TruSeq RNA Sample Prep Kit was used with 1 ug of total RNA for the construction of sequencing libraries.RNA libraries were prepared for sequencing using standard Illumina protocols.Sequenced reads were trimmed for adaptor sequence, and masked for low-complexity or low-quality sequence, then mapped to mm10 whole genome using bowtie2-2.2.5 with parameters -p 8 --bowtie2 -sensitivity-level very_sensitive.
Project description:Purpose: Cadmium is a nonessential heavy metal and a well known toxic agent. Cadmium is known to alter the gene expression and signaling but the role of miRNAs during Cadmium exposure is not understood. Methods: Mice were treated with 100 mg/ ml cadmium chloride for 120 days and accumulation of cadmium in blood and organs are confirmed by GFAAS. Subsequently, the total RNA was isolated from the whole blood and small RNA sequencing was executed in Illumina HiSeq 1000. Results: The reads were annotated to the mice genome and miRNAs in miRbase using miRDeep* and novel miRNAs were also predicted. The differential expression was studied by DeSeq Conclusions: This is the first report to reveal the cadmium responsive miRNome. These candidate miRNAs can serve as biomarkers for cadmium Whole blood small RNA profiles of control and cadmium exposed mice generated by deep sequencing using Illumina HiSeq 1000
Project description:Hematopoietic stem cells (HSCs) are at the basis of the hematopoietic hierarchy. Their ability to self-renew and differentiate is strictly controlled by molecular signals produced by their surrounding micorenvironments composed of stromal cells. HSCs first emerge in the AGM (Aorta Gonads Mesonephros) region, amplify in the fetal liver (FL) and are maintained in the adult bone marrow (BM). To further characterize the molecular program of the HSC niches, we have compared the global transcriptome of HSC-supportive and non-supportive stromal clones established from the AGM, FL and BM. Hematopoietic stem cells (HSCs) are at the basis of the hematopoietic hierarchy. Their ability to self-renew and differentiate is strictly controlled by molecular signals produced by their surrounding micorenvironments composed of stromal cells. HSCs first emerge in the AGM (Aorta Gonads Mesonephros) region, amplify in the fetal liver (FL) and are maintained in the adult bone marrow (BM). To further characterize the molecular program of the HSC niches, we have compared the global transcriptome of HSC-supportive line from Fetal Calvaria (OP9) and non-supportive stromal clones from fetal liver (BFC). Hematopoietic stem cells (HSCs) are at the basis of the hematopoietic hierarchy. Their ability to self-renew and differentiate is strictly controlled by molecular signals produced by their surrounding micorenvironments composed of stromal cells. HSCs first emerge in the AGM (Aorta Gonads Mesonephros) region, amplify in the fetal liver (FL) and are maintained in the adult bone marrow (BM). To further characterize the molecular program of the HSC niches, we have compared the global transcriptome of HSC-supportive and non-supportive stromal clones established from fetal liver. We took advantage of stromal clones established from the AGM, FL and BM and tested for their ability to support or not HSCs ex vivo. RNA were extracted from confluent stromal cultures or sorted cells and used for hybridization of Affymetrix (mouse gene 1.0 ST) microarrays.
Project description:In order to determine the role of the transcription factor Arntl2 in regulating metastatic ability and identify Arntl2-dependent transcriptonal targets in metastatic lung adenocarcinoma, we sequenced the mRNA from 3 mouse metastasis cell lines. Each of these cell lines (482N1shLuciferase, 482N1shArntl2#1, and 482N1shArntl2#2) were derived from the same parental cell line, 482N1. 482N1 was derived from a lymph node metastasis of a Kras LSL G12D, p53 flox/flox 129S1/SvlmJ mouse model of metastatic lung adenocarcinoma. A comparison of shLuciferase and shArntl2 cell lines reveals Arntl2-dependent changes in the metastatic transcriptome. This study includes 6 samples: 2 biological replicates of 482N1 shLuciferase, 2 biological replicates of 482N1 shArntl2#1, and 2 biological replicates of 482N1shArntl2#2. Poly-A RNA was isolated and prepared for sequencing using the Illumina TruSeq RNA kit (v2) to generate 100bp paired end reads. Reads were aligned to mm10.
Project description:To determine the different gene signatures between primary tumor and tumor-derived exosomes, we have employed RNA-sequencing as a discovery platform to identify gene signatures of tumor-derived exosomes, taking the original tumors as a control. We subcutaneously inoculated C57BL/6 mice with Lewis lung carcinoma (LLC). Three weeks later, tumor tissues were cut and tumor-derived exosomes were isolated as described in the "treatment protocol". Then, both exosomal RNA and tumor RNA were extracted and sequenced. From sequencing, we found that exosomal RNAs showed quite different transcript profiles from tumor RNAs. Examination of different gene signatures between primary tumor and tumor-derived exosomes. 2 replicates each.