Interleukin-17 (IL-17) is essential in host defense against extracellular bacteria and fungi, especially at mucosal sites, but it also contributes significantly to inflammatory and autoimmune disease pathologies. Binding of IL-17 to its receptor leads to recruitment of the adaptor protein CIKS/Act1 via heterotypic association of their respective SEFIR domains and to activation of the transcription factor NF-kB; it is not known whether CIKS and/or NF-kB are required for all gene induction events. Here we report that CIKS is essential for all IL-17 induced immediate-early genes in primary mouse embryo fibroblasts, while NF-kB is profoundly involved. We also identify a novel sub-domain in the N-terminus of CIKS that is essential for IL-17-mediated NF-kB activation. This domain is both necessary and sufficient for the interaction between CIKS and TRAF6, an adaptor required for NF-kB activation. The ability of decoy peptides to block this interaction may provide a new therapeutic strategy for intervention in IL-17-driven autoimmune and inflammatory diseases.
IL-17-induced NF-kappaB activation via CIKS/Act1: physiologic significance and signaling mechanisms.
Specimen part, Treatment
View SamplesGiven the dearth of new antibiotics, host-directed therapies (HDTs) are especially desirable. Since IFN-gamma (IFN) plays a central role in host resistance to intracellular bacteria, including Mycobacterium tuberculosis, we searched for small molecules to augment the IFN response in macrophages. Using a novel screen we identified a compound belonging to the rocaglate family(CMLD009433) that synergize with a sub-threshold concentration of IFN to enhance macrophage activation.
Fine-tuning of macrophage activation using synthetic rocaglate derivatives.
Specimen part, Treatment
View SamplesLive antigen-specific CD4 T cells are identified typically by tetramer staining or by staining of cytokines captured on the cell surface by bi-functional antibodies. We attempted identification of mycobacteria specific CD4 T cells using CD154 staining. In this method, splenocytes were stimulated with appropriate antigens in the presence of monensin and fluorochrome-conjugated anti-CD154 antibody. Antigen-specific cells will be stained positive for CD154. We performed microarrays with CD154 positive and negative CD4 T cells.
Transcriptome Analysis of Mycobacteria-Specific CD4<sup>+</sup> T Cells Identified by Activation-Induced Expression of CD154.
Specimen part
View SamplesResistance to amebiasis is associated with a polymorphism in the leptin receptor. Previous studies demonstrated that humans with the ancestral Q223 leptin receptor allele were nearly four times less likely to be infected with Entamoeba histolytica than those carrying the mutant R223 allele. We hypothesized that the Q223 allele protected against E. histolytica via STAT3-mediated transcription of genes required for mucosal immunity. To test this, mice containing the humanized LEPR Q or R allele at codon 223 were intracecally infected with E. histolytica. Susceptibility to amebiasis was assessed, and cecal tissues analyzed for changes in gene expression. By 72 h post-challenge all Q223 mice had cleared E. histolytica, whereas 39% of 223R mice were infected. 37 genes were differentially expressed in response to infection at 72 h, including pro-inflammatory genes (CXCL2, calprotectin (S100A8/9), Pla2g7, Itbg2, and MMP9) and functions pertaining to the movement and activity of immune cells. A comparison at 12 h post-challenge of infected Q223 vs. R223 mice identified a subset of differentially-expressed genes, many of which were closely linked to leptin signaling. Further analyses indicated that the Q223 gene expression pattern was consistent with a suppressed apoptotic response to infection, while 223R showed increased cellular proliferation and recruitment. These studies are the first to illuminate the downstream effects of leptin receptor polymorphisms on intestinal infection by E. histolytica. As such, they are important for the insight that they provide to this previously uncharacterized mechanism of mucosal immunity. Resistance to amebiasis is associated with a polymorphism in the leptin receptor. Previous studies demonstrated that humans with the ancestral Q223 leptin receptor allele were nearly four times less likely to be infected with Entamoeba histolytica than those carrying the mutant R223 allele. We hypothesized that the Q223 allele protected against E. histolytica via STAT3-mediated transcription of genes required for mucosal immunity. To test this, mice containing the humanized LEPR Q or R allele at codon 223 were intracecally infected with E. histolytica. Susceptibility to amebiasis was assessed, and cecal tissues analyzed for changes in gene expression. By 72 h post-challenge all Q223 mice had cleared E. histolytica, whereas 39% of 223R mice were infected. 37 genes were differentially expressed in response to infection at 72 h, including pro-inflammatory genes (CXCL2, calprotectin (S100A8/9), Pla2g7, Itbg2, and MMP9) and functions pertaining to the movement and activity of immune cells. A comparison at 12 h post-challenge of infected Q223 vs. R223 mice identified a subset of differentially-expressed genes, many of which were closely linked to leptin signaling. Further analyses indicated that the Q223 gene expression pattern was consistent with a suppressed apoptotic response to infection, while 223R showed increased cellular proliferation and recruitment. These studies are the first to illuminate the downstream effects of leptin receptor polymorphisms on intestinal infection by E. histolytica. As such, they are important for the insight that they provide to this previously uncharacterized mechanism of mucosal immunity.
Effect of the leptin receptor Q223R polymorphism on the host transcriptome following infection with Entamoeba histolytica.
Specimen part, Time
View SamplesA delay in the mammalian inflammatory response is a prominent feature of infection with Yersinia pestis, the agent of bubonic and pneumonic plague. Y. pestis factors have been identified that either do not stimulate a normal inflammatory response, or actively suppress it. Prominent among these are components of the Type III secretion system that is encoded on the Yersinia virulence plasmid (pYV). We used a rat model of bubonic plague to characterize the kinetics and extent of the mammalian transcriptomic response to infection with wild-type or pYV-negative Y. pestis in the draining lymph node. Remarkably, dissemination and multiplication of wild-type Y. pestis during the bubonic stage of disease did not induce any detectable gene expression response by host lymph node cells. This was followed, however, by an extensive transcriptomic response, including upregulation of several cytokine, chemokine, and other immune response genes, after systemic spread during septicemic plague. Matched lymph node samples used for histopathology and extracellular cytokine measurements, combined with the microarray data set, broadly outlined the mammalian immune response to Y. pestis and how it is influenced by pYV-encoded factors. The results indicate that both WT and pYV Y. pestis induce primarily a Th17 response, and not a Th1 or Th2 response. In the absence of pYV, a sustained recruitment of polymorphonuclear leukocytes, the major Th17 effector cell, to the lymph node resulted in clearance of infection. Thus, the ability to counteract a Th17- driven PMN response in the lymph node appears to be a major function of the Y. pestis virulence plasmid. In contrast, classic markers of the proinflammatory response and macrophage activation, such as TNF- and IFN-, were not induced at all by pYV Y. pestis, and appeared only late in infection with WT Y. pestis.
Transcriptomic and innate immune responses to Yersinia pestis in the lymph node during bubonic plague.
Sex, Specimen part, Treatment, Time
View SamplesChronic hepatitis C virus (HCV) infection is now routinely treated with interferon (IFN)-free regimens composed of directly acting antiviral (DAA) agents. Changes in hepatic and peripheral innate and adaptive immune function during DAA therapy associate with achieving a sustained virologic response (SVR). The present study explored the impact of cirrhosis on host endogenous interferon pathways during DAA therapy. mRNA and micro-RNA (miRNA) expression profiling was performed on paired pre- and end-of-treatment (EOT) liver biopsies from subjects treated with a 2 DAA regimen (sofosbuvir/ledipasvir [SOF/LDV]) for 12 weeks (n=4, 3 with cirrhosis) or a 3 DAA regimen (SOF/LDV with GS-9669 or GS-9451) for 6 weeks (n=6, 0 with cirrhosis). Nine of ten subjects achieved SVR, with one relapse in the GS-9669 treatment arm (ISHAK fibrosis 4). Hepatic interferon-stimulated gene expression was down-regulated in the liver of all subjects, with no observable impact of cirrhosis or duration of treatment. Hepatic down-regulation of all type-III IFNs was observed (IFNL1, IFNL2, IFNL3, IFNL4-G), while IFNA2 expression, undetectable in all subjects pre-treatment, was detected in 3 of 9 subjects at EOT (all 3 achieved SVR). Only the subject who relapsed had detectable IFNL4-G expression in EOT liver. No change in IFNB1, IFNG, or IFNA5 expression was observed, and expression of other type-I IFNs (IFNA1, IFNA4, IFNA5, IFNA6, IFNA8, IFNA16, IFNA17) was not detected pre- or post-treatment. While expression of multiple miRNAs changed in liver tissue over the course of treatment, most miRNAs previously associated with HCV replication, innate interferon signaling, and hepatic fibrosis did not change significantly. Conclusions: Changes in the host IFN-response during DAA therapy associate with favorable treatment outcome regardless of composition and duration of therapy or extent of hepatic fibrosis.
Achieving sustained virologic response after interferon-free hepatitis C virus treatment correlates with hepatic interferon gene expression changes independent of cirrhosis.
No sample metadata fields
View SamplesChlamydia trachomatis serovariants are responsible for either Trachoma, the leading cause of infectious blindness or sexually transmitted disease, wherein the endocervix is the most frequently infected site in women. Disease caused by Chlamydia typically involves chronic inflammation and scarring. Recent work with a live-attenuated A2497 plasmid deficient vaccine strain (A2497-) demonstrated protection in nonhuman primates against trachoma and a lack of measurable ocular pathology in A2497- infected monkeys. We therefore performed host cell transcriptome analysis of Hela cells infected with A2497 plasmid-containing (A2497) and A2497- Chlamydia over time. Our results indicate that relative to wild type A2497, the A2497- variant illicits a transcriptome response indicative of lowered inflammation response a delayed apoptosis response, a reduction in immune cell recruitement cytokine expression and a reduction in genes involved in cell proliferation and or fibrosis-like activities. The data provided here suggests a model that may explain how plasmid deficient chlamydia may provide an immuno-protective response without the pathology normally seen with plasmid-containing bacteria.
Transcriptional profiling of human epithelial cells infected with plasmid-bearing and plasmid-deficient Chlamydia trachomatis.
Disease, Cell line
View SamplesIn this manuscript, we present a more extensive analysis of inflammatory suppression mediated by L. plantarum at the respiratory tract. Via full genome microarray of whole lung tissue, we have generated an extensive list of soluble proinflammatory mediators that are expressed in response to PVM infection and we identify those mediators that are suppressed and also those that are not suppressed in response to L. plantarum priming. We focused further study on three specific virus-induced soluble mediators that are differentially expressed and that serve as specific biomarkers for Lactobacillus-mediated survival in response to acute respiratory virus infection. Among several novel directions, we use these biomarker cytokines to explore Lactobacillus-mediated actions at the respiratory tract that are unique and distinct from those taking place at gastrointestinal mucosa.
Immunobiotic Lactobacillus administered post-exposure averts the lethal sequelae of respiratory virus infection.
Specimen part
View SamplesA major limitation in the cancer treatment is the ability of cancer cells to become resistant to chemotherapeutic drugs, by multidrug establishment. Here, we evaluate the possibility to utilize MC70, either as ABC transporters inhibitor or as anticancer agent, in monotherapy or in combination with doxorubicin for cancer treatment. The study was carried out in MCF7/ADR and Caco-2, breast and colon cancer cells, respectively. Cell growth and apoptosis were measured by MTT assay and DNA laddering Elisa kit, respectively. Cell cycle perturbation and cellular targets modulation were analyzed by flowcytometry and western blotting, respectively. MC70 was analyzed for its interaction with ABC transporters, MDR-1, BCRP and MRP-1, and for its anticancer activity. In MCF7/ADR, MC70 slight inhibited cell proliferation and strongly enhanced doxorubicin effectiveness; conversely in Caco-2, it inhibited cell growth without affecting doxorubicin efficacy. In addition, it induced apoptosis, canceled in favor of necrosis when it was given in combination with high doses of the anthracycline. Moreover, MC70 inhibited cell migration probably through its residual activity as sigma-1 ligand. Among the hypothesized molecular and cellular mechanisms responsible for all these effects, modulations of cell cycle, of pAkt and of the three MAPKs phosphorylation were evidenced while activity at transcription level was excluded. MC70 can be considered as a potential new anticancer agent with the capability to enhance doxorubicin effectiveness and an interesting role in the treatment of chemotherapy resistant tumors.
MC70 potentiates doxorubicin efficacy in colon and breast cancer in vitro treatment.
Cell line, Treatment
View SamplesRegulatory T cells (Tregs) play a cardinal role in the immune system by suppressing detrimental autoimmune responses, but their role in acute and chronic infectious diseases remains unclear. We recently demonstrated that IFN-??? receptor (IFNAR) signaling promotes Treg function in autoimmunity. To dissect the functional role of IFNAR-signaling in Tregs during acute and chronic viral infection, we infected Treg-specific IFNAR deficient (IFNARfl/flxFoxp3YFP-Cre) mice with LCMV Armstrong and Clone-13. In both models, IFNARfl/flxFoxp3YFP-Cre mice Tregs expressed enhanced expression of Treg associated activation antigens. The enhanced activated phenotype was also seen when we compared the transcriptomes of IFNARfl/flxFoxp3YFP-Cre and wild type (WT) Tregs by RNA-Seq on day 25-post Clone-13 infection. LCMV-specific CD8+ T cells from IFNARfl/flxFoxp3YFP-Cre mice produced less antiviral IFN? and TNF? in both acute and chronic LCMV. In the chronic model, the numbers of anti-viral effector and memory CD8+ T cells were decreased in IFNARfl/flxFoxp3YFP-Cre mice and the effector CD4+ and CD8+ T cells exhibited a phenotype compatible with enhanced exhaustion. IFNARfl/flxFoxp3YFP-Cre mice cleared Armstrong infection normally, but had higher viral titers in sera, kidneys and lungs than WT mice during chronic infection. Thus, type I IFN signaling in Tregs is context-dependent, resulting in enhanced suppressor function in some models of autoimmunity, but decreased suppressor function in acute and chronic viral infection. Overall design: mRNA from Treg cells from 5 WT and 5 IFNAR deficient mice were analyzied by RNA-seq using Illumina HiSeq
Type I interferon signaling attenuates regulatory T cell function in viral infection and in the tumor microenvironment.
Cell line, Subject
View Samples