A deletion in the CMAH gene in humans occurred approximately 3.5 million years ago. This resulted in the inactivation of the CMP-Neu5Ac hydroxylase enzyme, and hence, in the specific deficiency in N-glycolylneuraminic acid (Neu5Gc), a form of sialic acid, in all modern humans. Although there is evidence that this molecular milestone in the origin of humans may have led to the evolution of human-specific pathogens, how deficiency in Neu5Gc might alter progression of non-infectious human diseases remains unanswered. Here, we have investigated cardiac and skeletal muscle gene expression changes in mdx mice, a model of Duchenne muscular dystrophy (DMD), that do or do not carry the human-like inactivating mutation in the mouse Cmah gene. We have evidence that Neu5Gc-deficiency in humans might explain some of the discrepancies in the disease phenotype between mdx mice and DMD patients.
A human-specific deletion in mouse Cmah increases disease severity in the mdx model of Duchenne muscular dystrophy.
Sex, Age, Specimen part
View SamplesA zebrafish forward genetic screen for determinants of susceptibility to Mycobacterium marinum identified a hypersusceptible mutant deficient in the lysosomal hydrolase Cathepsin L that manifests the hallmarks of human lysosomal storage diseases. In uninfected mutants, macrophages progressively accumulate undigested material in their lysosomes, leading to impaired migration and the accumulation of unengulfed cell debris. During mycobacterial infection, these vacuolated macrophages cannot migrate to phagocytose infected macrophages undergoing apoptosis in the tuberculous granuloma. Consequently, unengulfed apoptotic macrophages undergo secondary necrosis causing granuloma breakdown and increased mycobacterial growth. Macrophage lysosomal accumulations similarly impair migration to newly infecting mycobacteria. We find that important aspects of this phenotype are recapitulated in human smokers, who are at increased risk for tuberculosis. A majority of alveolar macrophages from smokers exhibit lysosomal accumulations and do not migrate to Mycobacterium tuberculosis. This incapacitation of highly microbicidal first-responding macrophages may contribute to smokers' susceptibility to tuberculosis. Overall design: A forward genetic screen for zebrafish larvae that are hypersusceptible to Mycobacterium marinum infection identified a mutation in the transcription factor snapc1b at 13: 37996163 (T->C). Individuals of wild type (T/T) and mutant (C/C) were genotyped and pooled respectively for RNA isolation and transcriptome analysis.
Lysosomal Disorders Drive Susceptibility to Tuberculosis by Compromising Macrophage Migration.
No sample metadata fields
View SamplesGoal: To examine the effects of human resistin during helminth infection. Methodology: To examine the function of human resistin (hResistin), we utilized transgenic mice expressing the human resistin gene along with its entire regulatory region (hRetnTg+). Following infection with the helminth Nippostrongylus brasiliensis, whole lung RNA was sequenced in hRetnTg+ mice, control hRetnTg- and naïve mice. Conclusion: In hRetnTg+ mice, many genes involved in inflammation and the immune system, specifically toll-like receptor signaling and chemokines, are significantly upregulated, suggesting that human resistin promotes TLR signaling and inflammation during helminth infection. Overall design: Examination of whole lung mRNA from Nippostrongylus brasiliensis-infected lungs at day 7 in mice expressing human resistin
Macrophage-derived human resistin is induced in multiple helminth infections and promotes inflammatory monocytes and increased parasite burden.
No sample metadata fields
View SamplesPirin (PIR) is a putative transcriptional regulator whose expression is silenced in cells bearing the AML1/ETO and PML/RAR leukemogenic fusion proteins and is significantly repressed in a large proportion of acute myeloid leukemias. PIR expression increases during in vitro myeloid differentiation of primary hematopoietic precursor cells, and ablation of PIR in the U937 myelomonocytic cell line or in murine primary hematopoietic precursor cells results in impairment of terminal myeloid differentiation.
Pirin downregulation is a feature of AML and leads to impairment of terminal myeloid differentiation.
Cell line
View SamplesThe neurobiological functions of a number of kinases expressed in the brain are unknown. Here, we report new findings on DCLK3 (Doublecortin-like kinase 3) which is preferentially expressed in neurons in the striatum and dentate gyrus. Its function has never been investigated. DCLK3 expression is markedly reduced in Huntington''s disease. Recent data obtained in studies related to cancer suggest DCLK3 could have anti-apoptotic effect. Thus, we hypothesized that early loss of DCLK3 in Huntington''s disease may render striatal neurons more susceptible to mutant huntingtin (mHtt). We discovered that DCLK3 silencing in the striatum of mice exacerbated the toxicity of an N-terminal fragment of mHtt. Conversely, overexpression of DCLK3 reduced neurodegeneration produced by mHtt. DCLK3 also produced beneficial effects on motor symptoms in a knock-in mouse model of Huntington''s disease. Using different mutants of DCLK3, we found that the kinase activity of the protein plays a key role in neuroprotection. To investigate the potential mechanisms underlying DCLK3 effects, we studied the transcriptional changes produced by the kinase domain in human striatal neurons in culture. Results show that DCLK3 regulates in a kinase-dependent manner the expression of many genes involved in transcription regulation and nucleosome/chromatin remodeling. Consistent with this, histological evaluation showed DCLK3 is present in the nucleus of striatal neurons and, protein-protein interaction experiments suggested that the kinase domain interacts with zinc finger proteins, including TADA3, a core component of SAGA complex. Our novel findings suggest that the presence of DCLK3 in striatal neurons may play a key role in transcription regulation and chromatin remodeling in these brain cells, and show that reduced expression of the kinase in Huntington's disease could render the striatum highly vulnerable to neurodegeneration. Examination of DCLK3 as neuroprotector against mutant huntingtin in vivo and in vitro models. Overall design: Examination of DCLK3 as neuroprotector against mutant huntingtin in vitro experiments.
The striatal kinase DCLK3 produces neuroprotection against mutant huntingtin.
Specimen part, Cell line, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Performance comparison of two microarray platforms to assess differential gene expression in human monocyte and macrophage cells.
Sex, Age, Specimen part
View SamplesThe present study was conducted to compare the ability of Affymetrix and Illumina microarray technologies to characterize the differential gene expression profiles of human monocytes and monocyte-derived-macrophages.
Performance comparison of two microarray platforms to assess differential gene expression in human monocyte and macrophage cells.
Sex, Age, Specimen part
View SamplesTriple-negative (TN) breast cancers need to be refined in order to identify therapeutic subgroups of patients.
Gene-expression molecular subtyping of triple-negative breast cancer tumours: importance of immune response.
Disease
View SamplesBackground: Type I interferons (IFNs) are essential to the clearance of viral diseases, in part by initiating upregulation of IFN regulated genes (IRGs). A clear distinction between genes upregulated directly by virus and genes upregulated by secondary IFN production has not been made. Here we investigated the genes regulated by IFN-a2b compared to the genes regulated by SARS-CoV infection in ferrets.
Early gene expression events in ferrets in response to SARS coronavirus infection versus direct interferon-alpha2b stimulation.
Specimen part
View SamplesThe 2009 H1N1 influenza pandemic has prompted a significant need for the development of efficient, single-dose, adjuvanted vaccines. Here we investigated the adjuvant potential of CpG oligodeoxynucleotide (ODN) when used with a human seasonal influenza virus vaccine in ferrets. We found that the CpG ODNadjuvanted vaccine effectively increased antibody production and activated type I interferon (IFN) responses compared to vaccine alone. Based on these findings, pegylated IFN- 2b (PEG-IFN) was also evaluated as an adjuvant in comparison to CpG ODN and complete Freunds adjuvant (CFA). Our results showed that all three vaccines with adjuvant added prevented seasonal human A/Brisbane/59/2007 (H1N1) virus replication more effectively than did vaccine alone. Gene expression profiles indicated that, as well as upregulating IFN-stimulated genes (ISGs), CpG ODN enhanced B-cell activation and increased Toll-like receptor 4 (TLR4) and IFN regulatory factor 4 (IRF4) expression, whereas PEG-IFN augmented adaptive immunity by inducing major histocompatibility complex (MHC) transcription and Ras signaling. In contrast, the use of CFA as an adjuvant induced limited ISG expression but increased the transcription of MHC, cell adhesion molecules, and B-cell activation markers. Taken together, our results better characterize the specific molecular pathways leading to adjuvant activity in different adjuvant-mediated influenza virus vaccinations.
Molecular characterization of in vivo adjuvant activity in ferrets vaccinated against influenza virus.
Specimen part, Treatment
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