The identification of inflammatory bowel disease (IBD) susceptibility genes by genome-wide association has linked this pathology to autophagy, a lysosomal degradation pathway that is crucial for cell and tissue homeostasis. Here, we describe autophagin-1 (ATG4B) as an essential protein in the control of inflammatory response during experimental colitis. In this pathological condition, ATG4B protein levels increase paralleling the induction of autophagy. Moreover, ATG4B expression is significantly reduced in affected areas of the colon from IBD patients. Consistently, atg4b-/- mice present Paneth cell abnormalities, as well as an increased susceptibility to DSS-induced colitis. Atg4b-deficient mice exhibit significant alterations in proinflammatory cytokines and mediators of the immune response to bacterial infections, which are reminiscent of those found in patients with Crohns disease or ulcerative colitis. Additionally, antibiotic treatments and bone marrow transplantation from wild-type mice reduced colitis in atg4b-/- mice. Taken together, these results provide additional evidence on the importance of autophagy in intestinal pathologies and describe ATG4B as a novel protective protein in inflammatory colitis. Finally, we propose that Atg4b-null mice are a suitable model for in vivo studies aimed at testing new therapeutic strategies for intestinal diseases associated with autophagy deficiency
ATG4B/autophagin-1 regulates intestinal homeostasis and protects mice from experimental colitis.
Sex, Age, Specimen part, Treatment
View SamplesTolerogenic dendritic cells (tol-DCs) offer a promising therapeutic potential for autoimmune diseases. Tol-DCs have been reported to inhibit immunogenic responses, yet little is known about the mechanisms controlling their tolerogenic status, as well as associated specific markers. Here we show that the anti-inflammatory TAM receptor tyrosine kinase MERTK, is highly expressed on clinical grade dexamethasone-induced human tol-DCs and mediates their tolerogenic effect. Neutralization of MERTK in allogenic mixed lymphocyte reactions as well as autologous DC-T cell cultures leads to increased T cell proliferation and IFN-g production. Additionally, we identify a previously unrecognized non-cell autonomous regulatory function of MERTK expressed on DCs. Recombinant Mer-Fc protein, used to mimic MERTK on DCs, suppresses nave and antigen-specific memory T cell activation. This mechanism is mediated by the neutralization of the MERTK agonist Protein S (PROS1) expressed by T cells. We find that MERTK and PROS1 are expressed in human T cells upon TCR activation and drive an autocrine pro-proliferative mechanism. Collectively, these results suggest that MERTK on tol-DCs directly inhibits T cell activation through the competition for PROS1 interaction with MERTK in the T cells. Targeting MERTK may provide an interesting approach to effectively increase or suppress tolerance for the purpose of immunotherapy.
MERTK as negative regulator of human T cell activation.
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View SamplesGlobal gene expression is altered in heart failure. This syndrome can be caused by cardiovascular diseases, including dilated cardiomyopathy (DCM), ischemic cardiomyopathy (ICM), hypertrophic cardiomyopathy, viral or toxic myocarditis, hypertension, and valvular diseases.
Differential gene expression of cardiac ion channels in human dilated cardiomyopathy.
Sex, Specimen part
View SamplesFull title: Genome-wide expression profiles of primary human small airway epithelial cells (SAECs) infected with different adenovirus mutants.
Heterochromatin silencing of p53 target genes by a small viral protein.
Specimen part
View SamplesA distinct highly invasive subpopulation was identified in breast cancer cell lines. The molecular characteristics of these cells was investigated, revealing a set of genes whose high expression confers the ability to invade.
ΔNp63α Promotes Breast Cancer Cell Motility through the Selective Activation of Components of the Epithelial-to-Mesenchymal Transition Program.
Cell line
View SamplesMesenchymal stromal cells (MSCs) sense and modulate inflammation and represent potential clinical treatment for immune disorders. However, many details of the bidirectional interaction between MSCs and the innate immune comaprtment are still unsolved. Here we describe an unconventional but functional interaction between pro-inflammatory classically activated macrophages (M1M) and MSCs, with CD54 playing a central role. CD54 was upregulated and enriched specifically at the contact area between M1M and MSCs. Moreover, the specific interaction induced calcium signaling and increased the immunosuppressive capacities of MSCs dependent on CD54 mediation. Our data demonstrate that MSCs can detect an inflammatory microenvironment via a direct and physical interaction with innate immune cells. This finding opens new perspectives for MSC-based cell therapy.
CD54-Mediated Interaction with Pro-inflammatory Macrophages Increases the Immunosuppressive Function of Human Mesenchymal Stromal Cells.
Specimen part
View SamplesBone-marrow mesenchymal stem cells (MSCs) are plastic adherent cells that can differentiate into various tissue lineages, including osteoblasts, adipocytes and chondrocytes. However, this progenitor property is not shared by all cells within the MSC population. In addition, MSCs vary in their proliferation capacities and expression of markers. Because of heterogeneity of CD146 expression in the MSC population, we compared CD146-/Low and CD146High cells under clonal and non-clonal (sorted MSCs) conditions to determine whether this expression is associated with specific functions. CD146-/Low and CD146High MSCs did not differ in colony-forming unit-fibroblast number, osteogenic and adipogenic differentiation or in vitro hematopoietic supportive activity. However, CD146-/Low clones proliferated slightly but significantly faster than did CD146High clones. In addition, a strong expression of CD146 molecule was associated with a commitment towards a vascular smooth muscle cell lineage with upregulation of calponin-1 expression. Thus, within a bone-marrow MSC population, certain subpopulations characterized by high expression of CD146, are committed toward a vascular smooth muscle cell lineage.
CD146 expression on mesenchymal stem cells is associated with their vascular smooth muscle commitment.
Specimen part, Subject
View SamplesTreatment of severely refractory Crohns disease (CD) patients remains a clinical challenge. Recent studies show efficacy of autologous hematopoietic stem cell transplant (HSCT) in these severely compromised patients. HSCT is thought to eliminate auto-reactive cells; however the mechanisms are incompletely understood. We followed a group of patients (n=18) receiving autologous HSCT, with 50% of them achieving endoscopic drug-free remission. To elucidate the mechanism driving efficacy we compared the immunological changes induced by HSCT in responders and non-responders.
Differences in peripheral and tissue immune cell populations following hematopoietic stem cell transplantation in Crohn's disease patients.
Sex, Age, Specimen part, Disease, Time
View SamplesTreatment of severely refractory Crohn's disease (CD) patients remains a clinical challenge. Recent studies show the efficacy of autologous hematopoietic stem cell transplant (HSCT) in these severely compromised patients. HSCT is thought to eliminate auto-reactive cells; however, no specific studies of immune reconstitution in CD patients are available. We studied a group of CD patients receiving autologous HSCT, with 50% of them achieving endoscopic drug-free remission. To elucidate the mechanism driving efficacy, we studied changes in the immune cell composition in tissue induced by HSCT. Overall design: Biopsy mRNA profiles of 14 CD patients undergoing HSCT were generated by deep sequencing, using HiSeq-4000 platform (Illumina, San Diego, CA).
Differences in Peripheral and Tissue Immune Cell Populations Following Haematopoietic Stem Cell Transplantation in Crohn's Disease Patients.
Sex, Specimen part, Disease, Subject
View SamplesFibroblast activation protein-a (FAP) identifies stromal cells of mesenchymal origin in human cancers and chronic inflammatory lesions. In mouse models of cancer, they have been shown to be immune suppressive, but studies of their occurrence and function in normal tissues have been limited. With a transgenic mouse line permitting the bioluminescent imaging of FAP(+) cells, we find that they reside in most tissues of the adult mouse. FAP(+) cells from three sites, skeletal muscle, adipose tissue, and pancreas, have highly similar transcriptomes, suggesting a shared lineage. FAP(+) cells of skeletal muscle are the major local source of follistatin, and in bone marrow they express Cxcl12 and KitL. Experimental ablation of these cells causes loss of muscle mass and a reduction of B-lymphopoiesis and erythropoiesis, revealing their essential functions in maintaining normal muscle mass and hematopoiesis, respectively. Remarkably, these cells are altered at these sites in transplantable and spontaneous mouse models of cancer-induced cachexia and anemia. Thus, the FAP(+) stromal cell may have roles in two adverse consequences of cancer: their acquisition by tumors may cause failure of immunosurveillance, and their alteration in normal tissues contributes to the paraneoplastic syndromes of cachexia and anemia. Overall design: FAP+ cells were sorted from two mesenchymal tissues, visceral adipose and skeletal muscle, and from an epithelial organ, the pancreas. These were compared to MEFs. Cells were isolated in duplicate experiments and these were analysed separately. These were compared to previously published publically available CD4+ T-cell subset data.
Depletion of stromal cells expressing fibroblast activation protein-α from skeletal muscle and bone marrow results in cachexia and anemia.
Specimen part, Subject
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