RNA sequencing was performed on uninjured, and injured (FSP1, and aSMA expressing) fibroblasts from mice hearts. Fibrosis accompanying wound healing can drive the failure of many different organs. Activated fibroblasts are the principal determinants of post-injury pathological fibrosis as well as physiological repair, making them a difficult therapeutic target. Fibroblasts are a heterogeneous cell population lacking unique functional classification. We demonstrated that FSP1 and aSMA expressing cells are distinct, post-injury fibroblasts in the heart, kidney, and skin and exhibit unique temporal expression patterns. Using mice that express GFP under the FSP1 or aSMA promoters, we isolated these fibroblasts from mouse hearts after myocardial infarction. Protein and transcript arrays, cellular assays as well as in vivo granulation tissue formation were used to determine their functional role(s) in healing and fibrosis. Whereas aSMA+ fibroblasts predominated in producing matrix proteins, FSP1+ fibroblasts significantly promoted angiogenesis. These studies have the potential to shift our focus towards viewing fibroblasts not only molecularly but also as functionally heterogeneous and provide a new paradigm with which to approach treatment for organ fibrosis. Overall design: Fibroblasts were isolated from uninjured BL6 mice for control. FSP1 and aSMA expressing fibroblasts were isolated from transgenic mice that express GFP under FSP1 or aSMA promoter. GFP positive cells were freshly sorted 10 days following myocardial infarction from mice ventricles. RNA was prepared using Ambion RNAqueous kit and submitted for RNA sequencing.
Identification of a pro-angiogenic functional role for FSP1-positive fibroblast subtype in wound healing.
Age, Specimen part, SubjectView Samples
Hepatitis C virus (HCV) infection is a major cause of chronic liver disease worldwide. The current standard therapy for chronic hepatitis C (CHC) consists of a combination of pegylated IFN alpha (pegIFN-alpha) and ribavirin. It achieves a sustained viral clearance in only 5060% of patients. To learn more about molecular mechanisms underlying treatment failure, we investigated IFN-induced signaling in paired liver biopsies collected from CHC patients before and after administration of pegIFN-alpha. In patients with a rapid virological response to treatment, pegIFN-alpha induced a strong up-regulation of IFN-stimulated genes (ISGs). As shown previously, nonresponders had high expression levels of ISGs before therapy. Analysis of posttreatment biopsies of these patients revealed that pegIFN-alpha did not induce expression of ISGs above the pretreatment levels. In accordance with ISG expression data, phosphorylation, DNA binding, and nuclear localization of STAT1 indicated that the IFN signaling pathway in nonresponsive patients is preactivated and refractory to further stimulation. Some features characteristic of nonresponders were more accentuated in patients infected with HCV genotypes 1 and 4 compared with genotypes 2 and 3, providing a possible explanation for the poor response of the former group to therapy. Taken together with previous findings, our data support the concept that activation of the endogenous IFN system in CHC not only is ineffective in clearing the infection but also may impede the response to therapy, most likely by inducing a refractory state of the IFN signaling pathway.
Interferon signaling and treatment outcome in chronic hepatitis C.
No sample metadata fieldsView Samples
We used microarray analysis to examine which genes are differentially expressed in mice that received a combination of fish oil and indomethacin.
Fish oil and indomethacin in combination potently reduce dyslipidemia and hepatic steatosis in LDLR(-/-) mice.
Specimen part, CompoundView Samples
Although new therapies have doubled the survival of multiple myeloma (MM) patients, this remains an incurable disease. It has been postulated that the so-called MM Cancer Stem Cells (MM-CSC) would be responsible for tumor initiation and relapse but their unequivocal identification remains unclear. Here, we investigated in a panel of MM cell lines the presence of CD20+ cells harboring a MM-CSC phenotype. Among the multiple cell lines investigated, only a small population of CD20dim+ cells (0.3%) in the RPMI-8226 cell line was found. CD20dim+ RPMI-8226 cells expressed the plasma cell markers CD38 and CD138 and were CD19-CD27-. Additionally, CD20dim+ RPMI-8226 cells did not exhibit stem-cell markers as shown by gene expression profiling and the aldehyde dehydrogenase (ALDH) assay. Moreover, we demonstrated that CD20dim+ RPMI-8226 cells are not essential for CB17-SCID mice engraftment and show lower self-renewal potential than the CD20- RPMI-8226 cells. These results do not support CD20+ expression for the identification of MM-CSC.
CD20 positive cells are undetectable in the majority of multiple myeloma cell lines and are not associated with a cancer stem cell phenotype.
No sample metadata fieldsView Samples
Mouse ES cells were stably transduced with a lentivirus expressing either wild-type KBP or the stable mutant KBP(KK/RR) and maintained in self-renewing growth conditions. RNA-seq was performed to assess mRNA expression differences caused by the stabilization of KBP. Overall design: 6 samples [a triplicate set for ES cells expressing wild-type KBP and a triplicate set expressing KBP(KK/RR)] were analyzed.
The TDH-GCN5L1-Fbxo15-KBP axis limits mitochondrial biogenesis in mouse embryonic stem cells.
Specimen part, SubjectView Samples
Despite recent advances in the treatment of multiple myeloma (MM), it remains an incurable disease potentially due to the presence of resistant myeloma cancer stem cells (MM-CSC). Although the presence of clonogenic cells in MM was described more than 30 years ago, the phenotype of MM-CSC is still a matter of debate, especially with respect to the expression of syndecan- 1 (CD138). Here, we demonstrate the presence of two subpopulations - CD138++ (95-99%) and CD138low (1-5%) - in eight MM cell lines. To find out possible stem-cell-like features, we have phenotypically, genomic and functionally characterized the two subpopulations. Our results show that the minor CD138low subpopulation is morphologically identical to the CD138++ fraction and does not represent a more immature B-cell compartment (with lack of CD19, CD20 and CD27 surface expression). Moreover, both subpopulations have similar gene expression and genomic profiles. Importantly, both CD138++ and CD138low subpopulations have similar sensitivity to bortezomib, melphalan and doxorubicin. Finally, serial engraftment in SCID mice shows that CD138++ as well as CD138low cells have self-renewal potential and they are also phenotypically interconvertible. Overall, our results differ from previously published data which attribute a B-cell phenotype to MM-CSC and urge the need to explore more reliable markers to discriminate true clonogenic myeloma cells.
Phenotypic, genomic and functional characterization reveals no differences between CD138++ and CD138low subpopulations in multiple myeloma cell lines.
Disease, Cell lineView Samples
MicroRNAs have been demonstrated to be deregulated in multiple myeloma (MM). We have previously reported the downregulation of miR-214 in MM compared to normal plasma cells. In the present study, we have explored the functional role of miR-214 in myeloma pathogenesis. Ectopic expression of miR-214 reduced cell growth and induced apoptosis of myeloma cells. In order to identify the potential direct target genes of miR-214 which could be involved in the biological pathways regulated by this miRNA, gene expression profiling of H929 myeloma cell line transfected with precursor miR-214 was carried out. Functional analysis revealed significant enrichment for DNA replication, cell cycle phase and DNA binding. We show that miR-214 directly down-regulates the expression of PSMD10, which encodes the oncoprotein gankyrin, and ASF1B, a histone chaperone required for DNA replication, by binding to their 3'-UTR. In addition, gankyrin inhibition induced an increase of P53 mRNA levels and subsequent up-regulation in CDKN1A (p21Waf1/Cip1) and BAX transcripts, which are direct transcriptional targets of p53. In conclusion, we demonstrate that miR-214 function as a tumor suppressor in myeloma by a positive regulation of p53 and inhibition of DNA replication.
Restoration of microRNA-214 expression reduces growth of myeloma cells through positive regulation of P53 and inhibition of DNA replication.
Cell lineView Samples
We recently reported that carbon monoxide (CO) has bactericidal activity. To understand its mode of action we analysed the gene expression changes occurring when Escherichia coli, grown aerobically and anaerobically, is treated with the carbon monoxide releasing molecule, CORM-2. The E. coli microarray analysis shows that E. coli CORM-2 response is multifaceted with a high number of differentially regulated genes spread through several functional categories, namely genes involved in inorganic ion transport and metabolism, regulators, and genes implicated in posttranslational modification, such as chaperones. CORM-2 has higher impact in E. coli cells grown anaerobically, as judged by the existence of repressed genes belonging to eight functional classes which are absent in aerobically CORM-2 treated cells. In spite of the relatively stable nature of the CO molecule, our results show that CO is able to trigger a significant alteration in the transcriptome of E. coli which necessarily has effects in several key metabolic pathways.
Exploring the antimicrobial action of a carbon monoxide-releasing compound through whole-genome transcription profiling of Escherichia coli.
No sample metadata fieldsView Samples
Skeletal (striated) muscle is one of the four basic tissue types, together with the epithelium, connective and nervous tissues. Lungs, on the other hand, develop from the foregut and among various cell types contain smooth, but not skeletal muscle. Therefore, during earlier stages of development, it is unlikely that skeletal muscle and lung depend on each other. However, during the later stages of development, respiratory muscle, primarily the diaphragm and the intercostal muscles, execute so called fetal breathing-like movements (FBMs), that are essential for lung growth and cell differentiation. In fact, the absence of FBMs results in pulmonary hypoplasia, the most common cause of death in the first week of human neonatal life. Most knowledge on this topic arises from in vivo experiments on larger animals and from various in vitro experiments. In the current era of mouse mutagenesis and functional genomics, it was our goal to develop a mouse model for pulmonary hypoplasia.
Role of skeletal muscle in lung development.
Specimen partView Samples
TREM-1 is an orphan immunoreceptor expressed on monocytes, macrophages, and neutrophils. TREM-1 associates with and signals via the adapter protein DAP12/TYROBP, which contains an immunoreceptor tyrosine-based activation motif (ITAM). TREM-1 activation by receptor cross-linking is pro-inflammatory, and can amplify cellular responses to Toll-like receptor (TLR) ligands such as bacterial lipopolysaccharide (LPS). To investigate the cellular consequences of TREM-1 activation, we have characterized global gene expression changes in human monocytes in response to TREM-1 cross-linking in comparison to and combined with LPS. Both TREM-1 activation and LPS up-regulate chemokines, cytokines, matrix metalloproteases, and PTGS/COX2, consistent with a core inflammatory response. However, other immunomodulatory factors are selectively induced, including SPP1 and CSF1 (i.e., M-CSF) by TREM-1 activation and IL-23 and CSF3 (i.e., G-CSF) by LPS. Additionally, cross-talk between TREM-1 activation and LPS occurs on multiple levels. While synergy in GM-CSF protein production is reflected in commensurate mRNA abundance, comparable synergy in IL-1b protein production is not. TREM-1 activation also attenuates the induction of some LPS target genes, including those that encode IL-12 cytokine family subunits. Whereas positive TREM-1 outputs are abolished by the PI3K inhibitor wortmannin, this attenuation is largely PI3K-independent. These experiments provide a detailed analysis of the cellular consequences of TREM-1 activation, and highlight some of the complexity in signal integration between ITAM- and TLR-mediated signaling.
Innate immune responses to TREM-1 activation: overlap, divergence, and positive and negative cross-talk with bacterial lipopolysaccharide.
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