The satellite cell is considered the major tissue-resident stem cell underlying muscle regeneration, however, multiple non-satellite cell myogenic progenitors have been identified. PW1/Peg3 is expressed in satellite cells as well as a subset of interstitial cells with myogenic potential termed PICs (PW1+ Interstitial Cells). PICs differ from satellite cells by their anatomical location (satellite cells are sublaminal and PICs are interstitial), they do not express any myogenic marker and arise from a Pax3-independent lineage. Upon isolation from juvenile muscle (1 to 3 weeks old), PICs are capable to form both skeletal and smooth muscle suggesting they constitute a more plastic population compared to satellite cells. We used microarrays to gain insight into the relantionship between PICs and satellite cells.
Defining skeletal muscle resident progenitors and their cell fate potentials.
Age, Specimen part
View SamplesPlasmacytoid dendritic cells (pDC) are the major source of type I interferons (IFN-I) during viral infections, in response to triggering of endosomal Toll Like Receptors (TLR) 7 or 9 by viral single-stranded RNA or unmethylated CpG DNA, respectively. IFN-I production in pDC occurs in specialized endosomes encompassing preformed signaling complexes of TLR7 or 9 with their adaptor molecule MyD88 and the transcription factor interferon regulatory factor 7 (IRF7). The triggering of TLR leads to IRF7 phosphorylation, nuclear translocation and binding to the promoters of the genes encoding IFN-I to initiate their transcription. pDC express uniquely high levels of IRF7 at steady state and this expression is further enhanced by positive IFN-I feedback signaling during viral infections. However, the specific cell-intrinsic roles of MyD88 versus IFN-I signaling in pDC responses to a viral infection have not been rigorously dissected. To achieve this aim, we generated mixed bone marrow chimera mice (MBMC) allowing to rigorously compare the gene expression profiles of WT versus Ifnar1-KO or MyD88-KO pDC isolated from the same animals at steady state or after infection with the mouse cytomegalovirus (MCMV). Our results indicate that, in vivo during MCMV infection, pDC undergo a major transcriptional reprogramming, under combined instruction of IFN-I, IFN- and direct TLR triggering. However, these different stimuli drive specific, largely distinct, gene expression programs. We rigorously determined which gene modules require cell-intrinsic IFN-I signaling for their induction in pDC during a physiological viral infection in vivo. We delineated non-redundant versus shared versus antagonistic responses with IFN-. We demonstrated that cell-intrinsic IFN-I responsiveness is dispensable for induction of the expression of all IFN-I/III genes and many cytokines or chemokines in pDC during MCMV infection, contrary to MyD88 signaling.
Molecular dissection of plasmacytoid dendritic cell activation <i>in vivo</i> during a viral infection.
Specimen part, Treatment
View SamplesThe goal of this experiment was to use global gene expression profiling to assess the global genetic reprogramming of different types of splenic mononuclear phagocytes early after MCMV infection in vivo. This study includes new samples (GSM3178486-GSM3178497; available below) profiling splenic CD11b+ conventional dendritic cells (cDC2), classical monocytes (cMo) and red pulp macrophages (RPM) from untreated or day 1.5 MCMV-infected mice together with re-analysis of previously published data in order to examine the similarities in the pDC gene expression profiles across datasets.
Molecular dissection of plasmacytoid dendritic cell activation <i>in vivo</i> during a viral infection.
Specimen part, Treatment
View SamplesDendritic cells (DCs) are a complex group of cells which play a critical role in vertebrate immunity. Spleen or lymph node resident DCs are subdivided into conventional DC (cDC) subsets (CD11b and CD8alpha in mouse; BDCA1 and BDCA3 in man) and plasmacytoid DCs (pDCs). It is currently unclear if these various DC populations belong to a unique hematopoietic lineage and if the subsets identified in the mouse and human systems are evolutionary homologs. To bring novel insights into these questions, we sought conserved genetic signatures for these DCs through the analysis of a compendium of genome-wide expression profiles of mouse or human leukocytes.
Novel insights into the relationships between dendritic cell subsets in human and mouse revealed by genome-wide expression profiling.
No sample metadata fields
View SamplesMurine Cytomegalovirus (MCMV) infection leads to the activation of various immune cells, including dendritic cells (DCs) and Natural Killer (NK) cells. This activation is partly driven by innate cytokines including IFN-I, which are induced early after infection. The objective was to address the role of different innate cytokines in shaping DC subsets and NK cell responses, in particular the role of cell intrinsic responses to IFN-I.
Differential responses of immune cells to type I interferon contribute to host resistance to viral infection.
Specimen part
View SamplesDendritic cells (DCs) are a complex group of cells which play a critical role in vertebrate immunity. They are subdivided into conventional DC (cDC) subsets (CD11b and CD8alpha in mouse) and plasmacytoid DCs (pDCs). Natural killer cells are innate lymphocytes involved in the recognition and killing of abnormal self cells, including virally infected cells or tumor cells. DCs and NK cells are activated very early upon viral infections and regulate one another. However, the global responses of DC and NK cells early after viral infection in vivo and their molecular regulation are not entirely characterized. The goal of this experiment was to use global gene expression profiling to assess the global genetic reprogramming of DC and NK cells during a viral infection in vivo, as compared to B lymphocytes, and to investigate the underlying molecular mechanisms
Differential responses of immune cells to type I interferon contribute to host resistance to viral infection.
Sex, Specimen part
View SamplesThe injection of the pathogen-associated molecular pattern Polyinosinic-polycytidylic acid (poly(I:C)) leads to the activation of various immune cells, including dendritic cells (DCs) and Natural Killer (NK) cells. This activation is due to different innate cytokines produced early after injection, in particular IFN-I. The objective of the study was to compare the pattern of expression of IFN-I stimulated genes between DC and NK cells.
Differential responses of immune cells to type I interferon contribute to host resistance to viral infection.
Specimen part
View SamplesConjugated linoleic acid (CLA), a class of fatty acids found in beef and dairy products, has been shown to inhibit tumorigenesis in a variety of cancer model systems. Based on previously well-documented anti-tumor activity of CLA in rodent models of breast cancer, a pilot study was initiated to examine the effect of dietary CLA in a well-established transgenic model of breast cancer. Western blots were performed for the detection of AKT, c-Src, ERK1/2, and Cdc24. CLA significantly increased tumor burden (p<0.1) independent of an increase in oncogenic signaling. Mammary gland whole mounts indicated a loss of mammary adipose and extensive epithelial expansion in CLA-treated animals. Microarray analysis indicated a significant reduction in cytoskeletal related genes with at least a two-fold decrease in five out of six CLA-fed animals compared to untreated controls. Reduction of Cdc42, a key regulator of cell adhesion and cytoskeletal arrangements, was confirmed at the protein level by western blot (p<0.01). These findings suggest that dietary CLA may advance the malignant phenotype by promoting a loss of cell polarity and adhesion in the mammary gland epithelium. This action may have serious clinical implications for a subset high-risk population and warrants further investigation.
Pilot study on the effects of dietary conjugated linoleic acid on tumorigenesis and gene expression in PyMT transgenic mice.
Sex, Age, Specimen part
View SamplesEpithelial ovarian cancer is a very heterogeneous disease and remains the most lethal gynaecological malignancy in the Western world. Rational therapeutic approaches need to account for interpatient and intratumoral heterogeneity in treatment design. Detailed characterization of in vitro models representing the different histological and molecular subtypes is therefore imperative. Strikingly, from ~100 available ovarian cancer cell lines the origin and which subtype they represent is largely unknown. We have extensively and uniformly characterized 39 ovarian cancer cell lines (with mRNA/microRNA expression, exon sequencing, dose response curves for clinically relevant therapeutics) and obtained all available information on the clinical features and tissue of origin of the original ovarian cancer to refine the putative histological subtypes. From 39 ovarian cell lines, 14 were assigned as high-grade serous, four serous-type, one low-grade serous and 20 non-serous type. Three morphological subtypes (21 Epithelial, 7 Round, 12 Spindle) were identified that showed distinct biological and molecular characteristics, including overexpression of cell movement and migration-associated genes for the Spindle subtype. Clinical validation showed a clear association of the spindle-like tumors with metastasis, advanced stage, suboptimal debulking and poor prognosis. In addition, the morphological subtypes associated with the molecular C1-6 subtypes identified by Tothill et al. [1], Spindle clustered with C1-stromal subtype, Round with C5-mesenchymal and Epithelial with C4 subtype. We provide a uniformly generated data resource for 39 ovarian cancer cell lines, the ovarian cancer cell line panel (OCCP). This should be the basis for selecting models to develop subtype specific treatment approaches, which is very much needed to prolong the survival of ovarian cancer patients.
Ovarian cancer cell line panel (OCCP): clinical importance of in vitro morphological subtypes.
Cell line
View SamplesHepatic gene expression analysis in mice fed control diet or diets supplemented with 1% Fraction 1 (haxane) or Fraction 2 (methanol) of Boswellia Serrata
Effects of Boswellia serrata in mouse models of chemically induced colitis.
No sample metadata fields
View Samples