Systemic Lupus Erythematosus (SLE) is a systemic autoimmune disease with a complex spectrum of cellular and molecular characteristics including several dramatic changes in the populations of ...peripheral leukocytes. These changes include general leukopenia, activation of B and T cells, and maturation of granulocytes. The manifestation of SLE in peripheral blood is central to the disease but is incompletely understood. A technique for rigorously characterizing changes in mixed populations of cells, microarray expression deconvolution, has been applied to several areas of biology but not to SLE or to blood. Here we demonstrate that microarray expression deconvolution accurately quantifies the constituents of real blood samples and mixtures of immune-derived cell lines. We characterize a broad spectrum of peripheral leukocyte cell types and states in SLE to uncover novel patterns including: specific activation of NK and T helper lymphocytes, relationships of these patterns to each other, and correlations to clinical variables and measures. The expansion and activation of monocytes, NK cells, and T helper cells in SLE at least partly underlie this disease's prominent interferon signature. These and other patterns of leukocyte dynamics uncovered here correlate with disease severity and treatment, suggest potential new treatments, and extend our understanding of lupus pathology as a complex autoimmune disease involving many arms of the immune system.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Genome-wide association studies (GWAS) in several populations have demonstrated significant association of the IL23R gene with IBD (Crohn's disease (CD) and ulcerative colitis (UC)) and psoriasis, ...suggesting that perturbation of the IL-23 signaling pathway is relevant to the pathophysiology of these diseases. One particular variant, R381Q (rs11209026), confers strong protection against development of CD. We investigated the effects of this variant in primary T cells from healthy donors carrying IL23R(R381) and IL23R(Q381) haplotypes. Using a proprietary anti-IL23R antibody, ELISA, flow cytometry, phosphoflow and real-time RT-PCR methods, we examined IL23R expression and STAT3 phosphorylation and activation in response to IL-23. IL23R(Q381) was associated with reduced STAT3 phosphorylation upon stimulation with IL-23 and decreased number of IL-23 responsive T-cells. We also observed slightly reduced levels of proinflammatory cytokine secretion in IL23R(Q381) positive donors. Our study shows conclusively that IL23R(Q381) is a loss-of-function allele, further strengthening the implication from GWAS results that the IL-23 pathway is pathogenic in human disease. This data provides an explanation for the protective role of R381Q in CD and may lead to the development of improved therapeutics for autoimmune disorders like CD.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Asthma is canonically thought of as a disorder of excessive Th2-driven inflammation in the airway, although recent studies have described heterogeneity with respect to asthma pathophysiology. We have ...previously described distinct phenotypes of asthma based on the presence or absence of a three-gene "Th2 signature" in bronchial epithelium, which differ in terms of eosinophilic inflammation, mucin composition, subepithelial fibrosis, and corticosteroid responsiveness. In the present analysis, we sought to describe Th2 inflammation in human asthmatic airways quantitatively with respect to known mediators of inflammation and intercellular communication. Using whole-genome microarray and quantitative real-time PCR analysis of endobronchial biopsies from 27 mild-to-moderate asthmatics and 13 healthy controls with associated clinical and demographic data, we found that asthmatic Th2 inflammation is expressed over a variable continuum, correlating significantly with local and systemic measures of allergy and eosinophilia. We evaluated a composite metric describing 79 coexpressed genes associated with Th2 inflammation against the biological space comprising cytokines, chemokines, and growth factors, identifying distinctive patterns of inflammatory mediators as well as Wnt, TGF-β, and platelet-derived growth factor family members. This integrated description of the factors regulating inflammation, cell migration, and tissue remodeling in asthmatic airways has important consequences for the pathophysiological and clinical impacts of emerging asthma therapeutics targeting Th2 inflammation.
Genome-wide association (GWA) studies offer a powerful unbiased method for the identification of multiple susceptibility genes for complex diseases. Here we report the results of a GWA study for ...Crohn's disease (CD) using family trios from the Quebec Founder Population (QFP). Haplotype-based association analyses identified multiple regions associated with the disease that met the criteria for genome-wide significance, with many containing a gene whose function appears relevant to CD. A proportion of these were replicated in two independent German Caucasian samples, including the established CD loci NOD2 and IBD5. The recently described IL23R locus was also identified and replicated. For this region, multiple individuals with all major haplotypes in the QFP were sequenced and extensive fine mapping performed to identify risk and protective alleles. Several additional loci, including a region on 3p21 containing several plausible candidate genes, a region near JAKMIP1 on 4p16.1, and two larger regions on chromosome 17 were replicated. Together with previously published loci, the spectrum of CD genes identified to date involves biochemical networks that affect epithelial defense mechanisms, innate and adaptive immune response, and the repair or remodeling of tissue.
Background:
Genome‐wide microarray expression analysis creates a comprehensive picture of gene expression at the cellular level. The aim of this study was to investigate differential intestinal gene ...expression in patients with Crohn's disease (CD) and controls with subanalysis of confirmed CD susceptibility genes, associated pathways, and cell lineage.
Methods:
In all, 172 biopsies from 53 CD and 31 control subjects were studied. Paired endoscopic biopsies were taken at ileocolonoscopy from five specific anatomical locations including the terminal ileum (TI) for RNA extraction and histology. The 41,058 expression sequence tags were analyzed using the Agilent platform.
Results:
Analysis of all CD biopsies versus controls showed 259 sequences were upregulated and 87 sequences were downregulated. Upregulated genes in CD included SAA1 (fold change FC +7.5, P = 1.47 × 10−41) and REGL (FC +7.3, P = 2.3 × 10−16), whereas cellular detoxification genes including‐SLC14A2 (FC‐2.49, P = 0.00002) were downregulated. In the CD TI biopsies diubiquitin (FC+11.3, P < 1 × 10−45), MMP3 (FC+7.4, P = 1.3 × 10−11), and IRTA1 (FC‐11.4, P = 4.7 × 10−12) were differentially expressed compared to controls. In the colon SAA1 (FC+6.3, P = 5.3 × 10−8) was upregulated and thymic stromal lymphopoietin (TSLP) (FC‐2.3, P = 2.7 × 10−6) was downregulated comparing noninflamed CD and control biopsies, and the colonic inflammatory CD signature was characterized by downregulation of the organic solute carriers‐SLC38A4, SLC26A2, and OST alpha. Of CD susceptibility genes identified by genome‐wide association scan IL‐23A, JAK2, and STAT3 were upregulated in the CD group, confirming the dysregulation of Th17 signaling.
Conclusions:
These data characterize the dysregulation of a series of specific inflammatory pathways highlighting potential pathogenic mechanisms as well as areas for translation to therapeutic targets. (Inflamm Bowel Dis 2010)
To understand the genetic predisposition to selective immunoglobulin A deficiency (IgAD), we performed a genome-wide association study in 430 affected individuals (cases) from Sweden and Iceland and ...1,090 ethnically matched controls, and we performed replication studies in two independent European cohorts. In addition to the known association of HLA with IgAD, we identified association with a nonsynonymous variant in IFIH1 (rs1990760G>A, P = 7.3 × 10−10) which was previously associated with type 1 diabetes and systemic lupus erythematosus. Variants in CLEC16A, another known autoimmunity locus, showed suggestive evidence for association (rs6498142C>G, P = 1.8 × 10−7), and 29 additional loci were identified with P < 5 × 10−5. A survey in IgAD of 118 validated non-HLA autoimmunity loci indicated a significant enrichment for association with autoimmunity loci as compared to non-autoimmunity loci (P = 9.0 × 10−4) or random SNPs across the genome (P < 0.0001). These findings support the hypothesis that autoimmune mechanisms may contribute to the pathogenesis of IgAD.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The Microbiology Society will be launching an open research platform in October 2021. Developed using funding from the Wellcome Trust and the Howard Hughes Medical Institute (HHMI), the platform will ...combine our current sound-science journal,
Access Microbiology
, with artificial intelligence (AI) review tools and many of the elements of a preprint server. In an effort to improve the rigour, reproducibility and transparency of the academic record, the
Access Microbiology
platform will host both preprints of articles and their Version of Record (VOR) publications, as well as the reviewer reports, Editor's decision, authors' response to reviewers and the AI review reports. To ensure the platform meets the needs of our community, in February 2020 we conducted focus group meetings with various stakeholders. Using articles previously submitted to
Access Microbiology
, we undertook testing of a range of potential AI review tools and investigated the technical feasibility and utility of including these tools as part of the platform. In keeping with the open and transparent ethos of the platform, we present here a summary of the focus group feedback and AI review tool testing.
A large-scale effort, termed the Secreted Protein Discovery Initiative (SPDI), was undertaken to identify novel secreted and transmembrane proteins. In the first of several approaches, a biological ...signal sequence trap in yeast cells was utilized to identify cDNA clones encoding putative secreted proteins. A second strategy utilized various algorithms that recognize features such as the hydrophobic properties of signal sequences to identify putative proteins encoded by expressed sequence tags (ESTs) from human cDNA libraries. A third approach surveyed ESTs for protein sequence similarity to a set of known receptors and their ligands with the BLAST algorithm. Finally, both signal-sequence prediction algorithms and BLAST were used to identify single exons of potential genes from within human genomic sequence. The isolation of full-length cDNA clones for each of these candidate genes resulted in the identification of >1000 novel proteins. A total of 256 of these cDNAs are still novel, including variants and novel genes, per the most recent GenBank release version. The success of this large-scale effort was assessed by a bioinformatics analysis of the proteins through predictions of protein domains, subcellular localizations, and possible functional roles. The SPDI collection should facilitate efforts to better understand intercellular communication, may lead to new understandings of human diseases, and provides potential opportunities for the development of therapeutics.
Tissue‐resident macrophages play an important role in defense against pathogens and perform key functions in organ homeostasis, innate and adaptive immunity. Tissue macrophages originate from blood ...monocytes that infiltrate virtually every organ in the body. Macrophages in different tissues share many characteristics, including their ability to migrate, phagocytose particles, metabolize lipids and present antigens. Morphologically they are quite heterogeneous, and some distinct functions have been reported. The gene expression profile of macrophages is reflective of both their shared and distinct biological functions. Here, we show that macrophages from murine spleen, liver and peritoneum display dramatically different expression profiles. Clusters of genes were found to represent unique biological functions related to adhesion, antigen presentation, phagocytosis, lipid metabolism and signal transduction. Some gene families, such as integrins, are differentially expressed among the macrophages resident in different tissues, suggesting that the tissue of residence influences their biological function.
Experimental nonhuman primate models of asthma exhibit multiple features that are characteristic of an eosinophilic/T helper 2 (Th2)-high asthma subtype, characterized by the increased expression of ...Th2 cytokines and responsive genes, in humans. Here, we determine the molecular pathways that are present in a house dust mite–induced rhesus asthma model by analyzing the genomewide lung gene expression profile of the rhesus model and comparing it with that of human Th2-high asthma. We find that a prespecified human Th2 inflammation gene set from human Th2-high asthma is also present in rhesus asthma and that the expression of the genes comprising this gene set is positively correlated in human and rhesus asthma. In addition, as in human Th2-high asthma, the Th2 gene set correlates with physiologic markers of allergic inflammation and disease in rhesus asthma. Comparison of lung gene expression profiles from human Th2-high asthma, the rhesus asthma model, and a common mouse asthma model indicates that genes associated with Th2 inflammation are shared by all three species. However, some pathophysiologic aspects of human asthma (ie, subepithelial fibrosis, angiogenesis, neural biology, and immune host defense biology) are better represented in the gene expression profile of the rhesus model than in the mouse model. Further study of the rhesus asthma model may yield novel insights into the pathogenesis of human Th2-high asthma.
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