Streptococcus suis is a major swine pathogen that can be transmitted to humans causing severe symptoms. A large human outbreak was described in China, where approximately 25% out of 215 infected humans developed an unusual streptococcal toxic shock-like syndrome (STSLS). Albeit increased expression of inflammatory mediators following infection by the Chinese S. suis strain was suggested as responsible for STSLS case severity, the mechanisms involved are still poorly understood. In this study, we investigated the host innate immune response to infection by either one of 3 strains of S. suis: 89-1591 (Canadian, intermediate virulence), P1/7 (European, high virulence), and SC84 (Chinese, epidemic strain). Using Illumina microarray and validating those results with qPCR and Luminex assay, infected mice showed elevated expression of mainly pro-inflammatory chemokine and cytokine genes. Generally, pro-inflammatory genes were expressed at a higher level in mice infected with S. suis strain SC84 > P1/7 > 89-1591. Interestingly, IFN was expressed at much higher levels only in mice infected with the S. suis strain SC84, which could potentially explain some of the STSLS symptoms. IFN-KO mice infected with SC84 showed better survival than WT mice while no differences was seen in mice infected with highly virulent P1/7 strain. Overall, our results show an important role of IFN in S. suis infections and might explain in part the increased virulence of SC84 responsible for a recent outbreak in China.
Exacerbated type II interferon response drives hypervirulence and toxic shock by an emergent epidemic strain of Streptococcus suis.
Sex, Specimen part
View SamplesStreptococcus suis is a major swine pathogen that can be transmitted to humans causing severe symptoms. A large human outbreak was described in China, where approximately 25% out of 215 infected humans developed an unusual streptococcal toxic shock-like syndrome (STSLS). Albeit increased expression of inflammatory mediators following infection by the Chinese S. suis strain was suggested as responsible for STSLS case severity, the mechanisms involved are still poorly understood. In this study, we investigated the host innate immune response to infection by either one of 3 strains of S. suis: 89-1591 (Canadian, intermediate virulence), P1/7 (European, high virulence), and SC84 (Chinese, epidemic strain). Using Illumina microarray and validating those results with qPCR and Luminex assay, infected mice showed elevated expression of mainly pro-inflammatory chemokine and cytokine genes. Generally, pro-inflammatory genes were expressed at a higher level in mice infected with S. suis strain SC84 > P1/7 > 89-1591. Interestingly, IFN was expressed at much higher levels only in mice infected with the S. suis strain SC84, which could potentially explain some of the STSLS symptoms. IFN-KO mice infected with SC84 showed better survival than WT mice while no differences was seen in mice infected with highly virulent P1/7 strain. Overall, our results show an important role of IFN in S. suis infections and might explain in part the increased virulence of SC84 responsible for a recent outbreak in China.
Exacerbated type II interferon response drives hypervirulence and toxic shock by an emergent epidemic strain of Streptococcus suis.
Sex, Specimen part
View SamplesStreptococcus suis is a major swine pathogen that can be transmitted to humans causing severe symptoms. A large human outbreak was described in China, where approximately 25% out of 215 infected humans developed an unusual streptococcal toxic shock-like syndrome (STSLS). Albeit increased expression of inflammatory mediators following infection by the Chinese S. suis strain was suggested as responsible for STSLS case severity, the mechanisms involved are still poorly understood. In this study, we investigated the host innate immune response to infection by either one of 3 strains of S. suis: 89-1591 (Canadian, intermediate virulence), P1/7 (European, high virulence), and SC84 (Chinese, epidemic strain). Using Illumina microarray and validating those results with qPCR and Luminex assay, infected mice showed elevated expression of mainly pro-inflammatory chemokine and cytokine genes. Generally, pro-inflammatory genes were expressed at a higher level in mice infected with S. suis strain SC84 > P1/7 > 89-1591. Interestingly, IFN was expressed at much higher levels only in mice infected with the S. suis strain SC84, which could potentially explain some of the STSLS symptoms. IFN-KO mice infected with SC84 showed better survival than WT mice while no differences was seen in mice infected with highly virulent P1/7 strain. Overall, our results show an important role of IFN in S. suis infections and might explain in part the increased virulence of SC84 responsible for a recent outbreak in China.
Exacerbated type II interferon response drives hypervirulence and toxic shock by an emergent epidemic strain of Streptococcus suis.
Sex, Specimen part
View SamplesThe bacterial product lipopolysaccharide (LPS) stimulates nuclear factor kB (NF-kB) signaling, which results in the production of proinflammatory cytokines, such as tumor necrosis factor-alpha (TNF-alpha), as part of the immune response. NF-kB target genes also include those encoding proteins that inhibit NF-kB signaling through negative feedback loops. By simultaneously studying the dynamics of the nuclear translocation of the NF-kB subunit RelA and the activity of a Tnf-driven reporter in a mouse macrophage cell line, Sung et al. found that the gene encoding RelA was also a target of NF-kB. Synthesis of RelA occurred only at higher concentrations of LPS and constituted a positive feedback loop that dominated over existing negative feedback mechanisms. Genes expressed in response to a high concentration of LPS were enriched for those involved in innate immune responses. Together, these data suggest that the RelA-dependent positive feedback loop enables macrophages to mount an effective immune only above a critical concentration of LPS.
Switching of the relative dominance between feedback mechanisms in lipopolysaccharide-induced NF-κB signaling.
Specimen part
View SamplesWe used microarrays to determine how the quality and quantity of peptide-MHC impact TCR-induced gene expression in vivo.
Distinct influences of peptide-MHC quality and quantity on in vivo T-cell responses.
No sample metadata fields
View SamplesThe innate immune system is the organisms first line of defense against pathogens. Pattern recognition receptors (PRRs) are responsible for sensing the presence of pathogen-associated molecules. The prototypic PRRs, the membrane-bound receptors of the Toll-like receptor (TLR) family, recognize pathogen-associated molecular patterns (PAMPs) and initiate an innate immune response through signaling pathways that depend on the adaptor molecules MyD88 and TRIF. Deciphering the differences in the complex signaling events that lead to pathogen recognition and initiation of the correct response remains challenging. Here we report the discovery of temporal changes in the protein signaling components involved in innate immunity. Using an integrated strategy combining unbiased proteomics, transcriptomics and macrophage stimulations with three different PAMPs, we identified differences in signaling between individual TLRs and revealed specifics of pathway regulation at the protein level.
Proteome and Secretome Analysis Reveals Differential Post-transcriptional Regulation of Toll-like Receptor Responses.
Specimen part, Cell line
View SamplesMgrR is a newly characterized Hfq dependent small RNA RNA. The expression of MgrR is regulated by Two component system, PhoPQ regulon, which senses low Mg2+ in environment. It has been reported that Hfq-binding sRNAs base pair with target RNAs, frequently leading to rapid degradation of target messages or, less frequently, to stabilization, both of which can be assayed by using microarrays. In order to search for the target genes of MgrR, we therefore examined the consequences of MgrR expression on mRNA abundance under two conditions. In condition 1, the chromosomal copy of mgrR was deleted and MgrR was expressed for 15 from an induced plac-mgrR plasmid and compared to cells carrying a vector induced for the same period. In condition 2, the expression of mRNAs was compared in wild-type cells (mgrR+) and the mgrR deletion strain, both grown in LB; because MgrR levels are fairly high under our normal growth conditions, this allowed analysis of both the direct and indirect (long-term) effects of MgrR.
A PhoQ/P-regulated small RNA regulates sensitivity of Escherichia coli to antimicrobial peptides.
No sample metadata fields
View SamplesThe stromal microenvironment plays a vital role in cancer initiation and progression. We performed a comparative expression profiling of pulmonary MSC derived from NSCLC and corresponding normal lung tissue of 5 newly diagnosed patients. The analysis indicated variable expression of genes involved in DNA repair, apoptosis, proliferation or angiogenesis between NSCLC-MSC and NLT-MSC.
Mesenchymal stem cells in non-small cell lung cancer--different from others? Insights from comparative molecular and functional analyses.
Specimen part, Subject
View SamplesTranscription termination factor Rho is essential in enterobacteria. We inhibited Rho activity with bicyclomycin and used microarray experiments to assess Rho function on a genome-wide scale. Rho is a global regulator of gene expression that matches E. coli transcription to translational needs. Remarkably, genes that are most repressed by Rho are prophages and other horizontally-acquired portions of the genome. Elimination of these foreign DNA elements increases resistance to bicyclomycin. Although rho remains essential, such reduced-genome bacteria no longer require Rho cofactors NusA and NusG. Thus, Rho termination, supported by NusA and NusG, is required to suppress the toxic activity of foreign DNA.
Termination factor Rho and its cofactors NusA and NusG silence foreign DNA in E. coli.
Compound
View SamplesTo determine whether the polyamide-Chl conjugate 1R-Chl would cause similar changes in global gene expression in K562 cells, affymetrix gene chip analysis was performed using 1R-Chl. Through class comparison analysis, 1R-Chl affected the levels of transcription and genes of interest were determined.
Small molecules targeting histone H4 as potential therapeutics for chronic myelogenous leukemia.
Sex, Age, Disease
View Samples