Tolerogenic 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 SamplesCrohn's Disease (CD) is a chronic inflammatory disease of the intestinal tract.
Commensal-Specific CD4(+) Cells From Patients With Crohn's Disease Have a T-Helper 17 Inflammatory Profile.
Sex, Age, Disease, Subject
View SamplesIn an accompanying paper we found specific localization of diabetogenic T cells only to islets of Langerhans bearing the specific antigen. Instrumental in the specific localization was the presence of intra-islet dendritic cells bearing the -cell-peptide-MHC complex. Here we report that the entry of diabetogenic CD4 T cells very rapidly triggered inflammatory gene expression changes in islets and vessels by up-regulating chemokines and adhesion molecules. VCAM-1 expression was notable in blood vessels and so was ICAM-1. ICAM-1 was also found on -cells. These expression changes induced the entry of non-specific T cells that otherwise did not localize to the islets. In contrast to the entry of diabetogenic CD4 T cells, the entrance of non-specific T cells required a chemokine response and VCAM-1 expression by the islets. Interferon-gamma was important for the early gene expression changes in the islets. By microarray analysis we detected up-regulation of a group of interferon-inducible genes as early as 8 hours post T cell transfer. These studies provide a baseline to examine the development of therapeutics that can modulate islet localization of diabetogenic T cells to control this autoimmune disease.
Entry of diabetogenic T cells into islets induces changes that lead to amplification of the cellular response.
Specimen part
View SamplesType 1 diabetes (T1D) is an autoimmune disease triggered by T cell reactivity to protein antigens produced by the -cells. Here we present a chronological compendium of transcriptional profiles from islets of Langerhans isolated from non-obese diabetic (NOD) mice ranging from 2 wks up to diabetes and compared to controls. Parallel analysis was made of cellular components of the islets. Myeloid cells populated the islets early during development in all mouse strains. This was followed by a type I interferon signature detectable at 4-6 wks of age only in diabetes susceptible mice. Concurrently, CD4 T cells were found within islets, many in contact with intra-islet antigen presenting cells. Early cellular signs of islet reactivity were detected by six wks. By 8 wks, NOD islets contained all major leukocytes populations and an inflammatory gene signature. This work establishes the natural transcriptional signature of T1D and provides a resource for future research.
Defining the transcriptional and cellular landscape of type 1 diabetes in the NOD mouse.
Specimen part
View SamplesWe demonstrate diverse roles of interferongamma (IFN-) in the induction and regulation of immune-mediated inflammation using a transfer model of autoimmune diabetes. The diabetogenic CD4+BDC2.5 (BDC) T cell clone upon transfer into NOD.scid mice induced destruction of islets of Langerhans leading to diabetes. Administration of a neutralizing antibody to IFN- (H22) resulted in long term protection (LTP) from diabetes, with inflammation but persistence of a significant, albeit decreased numbers of -cells. BDC T cells were a mixture of cells expressing high, intermediate and low levels of the T cell receptor. Clonotype-low BDC T cells were required for LTP. Furthermore, islet infiltrating leukocytes in the LTP mice contained Foxp3+CD4 T cells. Islet inflammation in both diabetic and LTP mice was characterized by heavy infiltration of macrophages. Gene expression profiles indicated that macrophages in diabetic mice were M1-type, while LTP mice contained M2-differentiated. The LTP was abolished if mice were treated with either an antibody depleting CD4 T cells, or a neutralizing antibody to CTLA-4, in this case, only at a late stage. Neutralization of IL-10, TGF-, GITR or CD25 had no effect. Transfer of only clonotype-high expressing BDC T cells induced diabetes but in contrast, H22 antibodies did not inhibit diabetes. While clonotype high T cells induced diabetes even when IFN- was neutralized, paradoxically, there was reduced inflammation and no diabetes if host myeloid cells lacked IFN- receptor. Hence, using monoclonal CD4 T cells, IFN- can have a wide diversity of roles, depending on the setting of the immune process.
IFN-gamma-dependent regulatory circuits in immune inflammation highlighted in diabetes.
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View SamplesTranscriptome study of 2 Saccharomyces cerevisiae W303 derivatives, one carrying GFP (control) and one carrying aSyn-GFP
Different 8-hydroxyquinolines protect models of TDP-43 protein, α-synuclein, and polyglutamine proteotoxicity through distinct mechanisms.
Specimen part, Disease, Cell line
View SamplesMultiple myeloma (MM) cells were treated with the BET inhibitor CPI203 alone and in combination with lenalidomide plus dexamethasone in vitro and in vivo (mouse xenograft).
The BET bromodomain inhibitor CPI203 improves lenalidomide and dexamethasone activity in <i>in vitro</i> and <i>in vivo</i> models of multiple myeloma by blockade of Ikaros and MYC signaling.
Specimen part, Cell line, Treatment
View SamplesLight initiates the seedling deetiolation transition by promoting major changes in gene expression mainly regulated by phytochrome (phy) photoreceptors. During the initial dark-to-light transition, phy photoactivation induces rapid changes in gene expression that eventually lead to the photomorphogenic development. Recent reports indicate that this process is achieved by phy-induced degradation of Phy-Interacting bHLH transcription Factors (PIFs) PIF1, PIF3 PIF4 and PIF5, which are partly redundant constitutive repressors of photomorphogenesis that accumulate in darkness. In order to test whether light/phy-regulated gene expression occurs through these PIFs, we have performed whole-genome expression analysis in the pif1pif3pif4pif5 quadruple mutant (pifq).
Definition of early transcriptional circuitry involved in light-induced reversal of PIF-imposed repression of photomorphogenesis in young Arabidopsis seedlings.
No sample metadata fields
View SamplesNOD mice deficient in the transcription factor Batf3 never develop diabetes. The goal of this study was to determine if NOD.Batf3-/- mice islets had any inflammatory signature associated with type 1 diabetes. Islets of Langerhans were isolated from NOD, NOD.Batf3-/-, and NOD.Rag1-/- and then compared to determine inflammatory gene profiles. At 6 and 8 weeks of age, NOD.Batf3-/- islets had an absence of inflammatory gene expression and were almost identical to uninflamed NOD.Rag1-/- islets. This work shows that absence of the Batf3 transcription factor is sufficient to prevent all the inflammatory sequelae of autoimmune diabetes.
A minor subset of Batf3-dependent antigen-presenting cells in islets of Langerhans is essential for the development of autoimmune diabetes.
Sex, Specimen part
View SamplesMechanisms of immune regulation may control proliferation of aberrant plasma cells (PCs) in patients with the asymptomatic monoclonal gammopathy of undetermined significance (MGUS) preventing progression to active multiple myeloma (MM). We investigated the role of CD85j (LILRB1), an inhibitory immune checkpoint for B cell function, in MM pathogenesis.
Loss of the Immune Checkpoint CD85j/LILRB1 on Malignant Plasma Cells Contributes to Immune Escape in Multiple Myeloma.
Specimen part, Cell line
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