TNF-like Ligand 1A Research Articles

TL1A is an epithelial alarmin that cooperates with IL-33 for initiation of allergic airway inflammation.

Epithelium-derived cytokines or alarmins, such as interleukin-33 (IL-33) and thymic stromal lymphopoietin (TSLP), are major players in type 2 immunity and asthma. Here, we demonstrate that TNF-like ligand 1A (TL1A) is an epithelial alarmin, constitutively expressed in alveolar epithelium at steady state in both mice and humans, which cooperates with IL-33 for early induction of IL-9high ILC2s during the initiation of allergic airway inflammation. Upon synergistic activation by IL-33 and TL1A, lung ILC2s acquire a transient IL-9highGATA3low "ILC9" phenotype and produce prodigious amounts of IL-9. A combination of large-scale proteomic analyses, lung intravital microscopy, and adoptive transfer of ILC9 cells revealed that high IL-9 expression distinguishes a multicytokine-producing state-of-activated ILC2s with an increased capacity to initiate IL-5-dependent allergic airway inflammation. Similar to IL-33 and TSLP, TL1A is expressed in airway basal cells in healthy and asthmatic human lungs. Together, these results indicate that TL1A is an epithelium-derived cytokine and an important cofactor of IL-33 in the airways.

An Overview of Emerging Trends and Technologies in Ulcerative Colitis


 This report provides an overview of the evolving therapeutic landscape for moderate to severe ulcerative colitis (UC), including recent changes to clinical practice guidelines, key trends in therapeutic strategies, and new or emerging treatment options, with a focus on biologics and small-molecule therapies.
 Recent guidelines on the medical management of patients with UC include those of the American Gastroenterological Association (AGA), American College of Gastroenterology (ACG), and European Crohn’s and Colitis Organisation (ECCO), which were published in 2019, 2020, and 2022, respectively. These guidelines provide an accurate reflection of how clinical practice has changed to incorporate newer therapies that have entered the market and newer evidence that has been published since the release of the Canadian guidelines in 2015. The ACG, AGA, and ECCO guidelines all recommend use of a tumour necrosis factor (TNF) antagonist, vedolizumab, or tofacitinib for induction of remission in patients with moderate to severe UC; the AGA and ECCO guidelines also recommend ustekinumab as an option and recommend vedolizumab over adalimumab, whereas the AGA guidelines recommend early use of biologic drugs over a step-up approach after failure of 5-aminosalicylates.
 Two important trends in therapeutic strategies for UC include changes in the use and definition of treatment targets and recommendations regarding therapeutic drug monitoring (TDM).
 
 The 2021 Selecting Therapeutic Targets in Inflammatory Bowel Disease (STRIDE-II) guidelines provide contemporary consensus recommendations for using new and updated targets throughout an individualized treatment timeline in patients with inflammatory bowel disease (IBD). Although histologic remission is not considered a formal UC treatment target in STRIDE-II, it is acknowledged as an adjunctive measure to endoscopic remission to represent a deeper level of healing and is the focus of many current studies.
 The use of TDM emerged from challenges associated with the use of older biologics (primarily TNF antagonists), which posed difficulties related to immunogenicity and dosing. The relevance of TDM for newer biologics with different mechanisms of action, reduced immunogenicity, and fixed dosing (e.g., vedolizumab and ustekinumab) is a topic of ongoing debate. Although AGA guidelines on TDM in IBD and expert consensus statements support the use of reactive TDM for patients with UC who lose response to a TNF antagonist, evidence gaps remain regarding appropriate use of proactive TDM, utility of TDM for small molecules and biologics outside of the TNF antagonist class, and consistent target concentration thresholds to guide dose changes.
 
 
 There is a substantial pipeline of new and emerging drugs for the treatment of adults with moderate to severe UC, with many in phase IIb or III of clinical development; several notable trends of emerging pharmacotherapies exist, including an increasing number of Janus kinase inhibitors, several therapies with biologic targets that are new in UC (e.g., interleukin-23 antibodies, TNF-like ligand 1A inhibitors), an increasing number of oral therapies, and the first combination of 2 biologic therapies in UC.
 The Canadian health care system should be prepared to adapt to the rapidly evolving treatment landscape and potential clinical practice changes in moderate to severe UC. Drugs with new mechanisms of action in the treatment area and the new paradigm of combination therapy with multiple biologics of different classes may lead to improved patient outcomes but can also further complicate the treatment decision-making process. Therefore, it is important for health care providers to stay up to date on new and upcoming treatment options, which may require educational initiatives for both providers and patients as well as updates to the Canadian treatment guidelines. Overall, potential changes on the horizon may have substantial implications for the health care system given the prevalence of UC in Canada, the costs of advanced therapies, and the increasing number of available treatment options.

Astragaloside IV regulates TL1A and NF-κB signal pathway to affect inflammation in necrotizing enterocolitis

AimThis study aims to explore the possible effect of Astragaloside IV (AS-IV) on necrotizing enterocolitis (NEC) neonatal rat models and verify the possible implication of TNF-like ligand 1 A (TL1A) and NF-κB signal pathway. MethodsNEC neonatal rat models were established through formula feeding, cold/asphyxia stress and Lipopolysaccharide (LPS) gavage method. The appearance, activity and skin as well as the pathological status of rats subjected to NEC modeling were assessed. The intestinal tissues were observed after H&E staining. The expression of oxidative stress biomarkers (SOD, MDA and GSH-Px) and inflammatory cytokines (TNF-α, IL-1β and IL-6) were detected by ELISA and qRT-PCR. Western blotting and immunohistochemistry were applied to detect expressions of TL1A and NF-κB signal pathway-related proteins. Cell apoptosis was assessed by TUNEL. ResultsNEC neonatal rat models were established successfully, in which TL1A was highly expressed and NF-κB signal pathway was activated, while TL1A and NF-κB signal pathway can be suppressed by AS-IV treatment in NEC rats. Meanwhile, inflammatory response in intestinal tissues was increased in NEC rat models and AS-IV can attenuate inflammatory response in NEC rats through inhibiting TL1A and NF-κb signal pathway. ConclusionAS-IV can inhibit TL1A expression and NF-κb signal pathway to attenuate the inflammatory response in NEC neonatal rat models.

Meloxicam Inhibits Apoptosis in Neurons by Deactivating Tumor Necrosis Factor Receptor Superfamily Member 25, Leading to the Decreased Cleavage of DNA Fragmentation Factor Subunit α in Alzheimer's Disease.

Neuronal apoptosis is considered to be a critical cause of Alzheimer's disease (AD). Recently, meloxicam has shown neuroprotective effects; however, the inherent mechanisms are highly overlooked. Using APP/PS1 transgenic (Tg) mice as in vivo animal models, we found that meloxicam inhibits apoptosis in neurons by deactivating tumor necrosis factor receptor superfamily member 25 (TNFRSF25), leading to the suppression of the expression of fas-associated protein with death domain (FADD) and the cleavage of DNA fragmentation factor subunit α (DFFA) and cysteine aspartic acid protease-3 (caspase 3) via β-amyloid protein (Aβ)-depressing mechanisms. Moreover, the meloxicam treatment blocked the effects of β-amyloid protein oligomers (Aβo) on stimulating the synthesis of tumor necrosis factor α (TNF-α) and TNF-like ligand 1A (TL1A) in neuroblastoma (N) 2a cells. TNF-α and TL1A induce apoptosis in neurons via TNFR- and TNFRSF25-dependent caspase 3-activating mechanisms, respectively. Knocking down the expression of TNFRSF25 blocked the effects of TL1A on inducing apoptosis in neurons by deactivating the signaling cascades of FADD, caspase 3, and DFFA. Consistently, TNFRSF25 shRNA blocked the effects of Aβo on inducing neuronal apoptosis, which was corroborated by the efficacy of meloxicam in inhibiting Aβo-induced neuronal apoptosis. By ameliorating neuronal apoptosis, meloxicam improved memory loss in APP/PS1 Tg mice.

Biosensors for inflammation as a strategy to engineer regulatory T cells for cell therapy

Engineered regulatory T cell (Treg cell) therapy is a promising strategy to treat patients suffering from inflammatory diseases, autoimmunity, and transplant rejection. However, in many cases, disease-related antigens that can be targeted by Treg cells are not available. In this study, we introduce a class of synthetic biosensors, named artificial immune receptors (AIRs), for murine and human Treg cells. AIRs consist of three domains: (a) extracellular binding domain of a tumor necrosis factor (TNF)-receptor superfamily member, (b) intracellular costimulatory signaling domain of CD28, and (c) T cell receptor signaling domain of CD3-ζ chain. These AIR receptors equip Treg cells with an inflammation-sensing machinery and translate this environmental information into a CD3-ζ chain-dependent TCR-activation program. Different AIRs were generated, recognizing the inflammatory ligands of the TNF-receptor superfamily, including LIGHT, TNFα, and TNF-like ligand 1A (TL1A), leading to activation, differentiation, and proliferation of AIR-Treg cells. In a graft-versus-host disease model, Treg cells expressing lymphotoxin β receptor-AIR, which can be activated by the ligand LIGHT, protect significantly better than control Treg cells. Expression and signaling of the corresponding human AIR in human Treg cells prove that this concept can be translated. Engineering Treg cells that target inflammatory ligands leading to TCR signaling and activation might be used as a Treg cell-based therapy approach for a broad range of inflammation-driven diseases.

Immune Complex Formation Is Associated With Loss of Tolerance and an Antibody Response to Both Drug and Target.

AMG 966 is a bi-specific, heteroimmunoglobulin molecule that binds both tumor necrosis factor alpha (TNFα) and TNF-like ligand 1A (TL1A). In a first-in-human clinical study in healthy volunteers, AMG 966 elicited anti-drug antibodies (ADA) in 53 of 54 subjects (98.1%), despite a paucity of T cell epitopes observed in T cell assays. ADA were neutralizing and bound to all domains of AMG 966. Development of ADA correlated with loss of exposure. In vitro studies demonstrated that at certain drug-to-target ratios, AMG 966 forms large immune complexes with TNFα and TL1A, partially restoring the ability of the aglycosylated Fc domain to bind FcγRIa and FcγRIIa, leading to the formation of ADA. In addition to ADA against AMG 966, antibodies to endogenous TNFα were also detected in the sera of subjects dosed with AMG 966. This suggests that the formation of immune complexes between a therapeutic and target can cause loss of tolerance and elicit an antibody response against the target.

TL1A/TNFR2 Axis Enhances Immunoregulatory Effects of Bone Marrow Derived Mesenchymal Stem Cell by Indian Hedgehog Signaling Pathway.

Background and ObjectivesThe immunomodulatory potential of mesenchymal stem cells (MSCs) can be regulated by a variety of molecules, especially cytokines. The inflammatory cytokine, TNF-like ligand 1A (TL1A), has been reported as an inflammation stimulator in-multiple autoimmune diseases. Here, we studied the effects of TL1A/TNF-receptor 2 (TNFR2) pathway on the therapeutic potency of bone marrow-derived MSCs (BMSCs).Methods and ResultsBMSCs, fibroblast-like synoviocytes (FLSs), and H9 and jurkat human T lymphocytes were used in this study. BMSCs paracrine activities, differentiation, proliferation, and migration were investigated after stimulation with TL1A, and intervened with anti-TNFR2. Additionally, the effects of TL1A on BMSCs therapeutic potency were evaluated by treating RA-FLSs, and H9 and jurkat T cells with TL1A-stimulated BMSCs conditioned medium (CM). Indian hedgehog (IHH) involvement was determined by gene silencing and treatment by recombinant IHH (rIHH). TL1A induced BMSCs stemness-related genes, COX-2, IL-6, IDO, TGF-β and HGF through TNFR2. Also, TL1A corrected biased differentiation and increased proliferation, and migration through TNFR2. Meanwhile, CM of TL1A-stimulated BMSCs decreased the inflammatory markers of RA-FLSs and T cells. Moreover, TL1A-stimulated BMSCs experienced IHH up-regulation coupled with NF-κB and STAT3 signaling up-regulation, while p53 and oxidative stress were down-regulated. Furthermore, treatment of BMSCs by rIHH increased their anti-inflammatory effects. More importantly, knockdown of IHH decreased the ability of TL1A-stimulated BMSCs to alleviating the inflammation in RA-FLSs and T cells.ConclusionsThis study reports the effects of TL1A/TNFR2 pathway on the biological behaviors and therapeutic potency of BMSCs through IHH. These findings could introduce novel procedures to increase the stemness of MSCs in cellular therapy.

TNF-like ligand 1A is associated with progression and prognosis of human gastric cancer.

PurposeThis study aimed to investigate the function of TNF-like ligand 1A (TL1A) in the tumorigenesis and progression of gastric cancer (GC).MethodsRNA-seq gene expression and clinical information for GC patients were obtained from The Cancer Genome Atlas (TCGA) database. Differentially expressed genes (DEGs) between GC tissue samples and normal controls were screened with the edgeR package. Identification of gene co-expression and functional enrichment analyses were performed with Pearson’s correlation analysis and gene set enrichment analysis (GSEA), respectively. Lastly, survival analysis was performed using the Kaplan-Meier method with the log rank test.ResultsTL1A expression in GC tissue samples were significantly higher than that in normal controls (LogFC=1.07 and P=8.90E-07). Moreover, 215 genes, co-expressed with TL1A, and 21 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were obtained. Next, the miRNA-lncRNA/mRNA network, comprising 7 miRNAs, 27 lncRNAs, and 21 mRNAs, was constructed based on key genes from intersections between co-expression analysis and GSEA. In addition, survival analysis results demonstrated that TL1A (P=2.6e−07) was significantly associated with the overall survival (OS) of GC patients.ConclusionTL1A was involved in the tumorigenesis and progression of GC, and was significantly associated with the OS of GC patients.

Activation of DR3 signaling causes loss of ILC3s and exacerbates intestinal inflammation

TNF-like ligand 1 A (TL1A) and death receptor 3 (DR3) are a ligand-receptor pair involved in the pathogenesis of inflammatory bowel disease. Group 3 innate lymphoid cells (ILC3s) regulate intestinal immunity and highly express DR3. Here, we report that activation of DR3 signaling by an agonistic anti-DR3 antibody increases GM-CSF production from ILC3s through the p38 MAPK pathway. GM-CSF causes accumulation of eosinophils, neutrophils and CD11b+CD11c+ myeloid cells, resulting in loss of ILC3s from the intestine in an IL-23-dependent manner and exacerbating colitis. Blockade of GM-CSF or IL-23 reverses anti-DR3 antibody-driven ILC3 loss, whereas overexpression of IL-23 induces loss of ILC3s in the absence of GM-CSF. Neutralization of TL1A by soluble DR3 ameliorates both DSS and anti-CD40 antibody-induced colitis. Moreover, ILC3s are required for the deleterious effect of anti-DR3 antibodies on innate colitis. These findings clarify the process and consequences of DR3 signaling-induced intestinal inflammation through regulation of ILC3s.

Innate lymphoid cells link gut microbes with mucosal T cell immunity

ABSTRACTDespite continuous exposure to trillions of microbes, the intestinal immune system protects the mucosa by balancing barrier protection, tolerance, and immunity. As both sentinel and effector, the mucosal innate immune system plays a central role in coordinating these responses. By integrating signals from the intestinal microbiota, mononuclear phagocytes (MNPs) serve as a critical link in regulating effector functions of group 3 innate lymphoid cells (ILC3s). Our recent work identified the role for MNP production of the IBD-linked protein TNF-like ligand 1A (TL1A) in modulating microbial regulation of ILC3 barrier immunity. These findings highlight a broader role for ILC3s in local control of T cell immunity and their potential role in the pathogenesis and treatment of inflammatory disease.

Microbiota-Induced TNF-like Ligand 1A Drives Group 3 Innate Lymphoid Cell-Mediated Barrier Protection and Intestinal T Cell Activation during Colitis

Inflammatory bowel disease (IBD) results from a dysregulated interaction between the microbiota and a genetically susceptible host. Genetic studies have linked TNFSF15 polymorphisms and its protein TNF-like ligand 1A (TL1A) with IBD, but the functional role of TL1A is not known. Here, we found that adherent IBD-associated microbiota induced TL1A release from CX3CR1+ mononuclear phagocytes (MNPs). Using cell-specific genetic deletion models, we identified an essential role for CX3CR1+MNP-derived TL1A in driving group 3 innate lymphoid cell (ILC3) production of interleukin-22 and mucosal healing during acute colitis. In contrast to this protective role in acute colitis, TL1A-dependent expression of co-stimulatory molecule OX40L in MHCII+ ILC3s during colitis led to co-stimulation of antigen-specific Tcells that was required for chronic Tcell colitis. These results identify a role for ILC3s in activating intestinal Tcells and reveal a central role for TL1A in promoting ILC3 barrier immunity during colitis.

A variant of death-receptor 3 associated with rheumatoid arthritis interferes with apoptosis-induction of T cell

Rheumatoid arthritis (RA) is a chronic polyarthritis of unknown etiology. To unravel the molecular mechanisms in RA, we performed targeted DNA sequencing analysis of patients with RA. This analysis identified a variant of the death receptor 3 (DR3) gene, a member of the family of apoptosis-inducing Fas genes, which contains four single-nucleotide polymorphisms (SNPs) and a 14-nucleotide deletion within exon 5 and intron 5. We found that the deletion causes the binding of splicing regulatory proteins to DR3 pre-mRNA intron 5, resulting in a portion of intron 5 becoming part of the coding sequence, thereby generating a premature stop codon. We also found that this truncated DR3 protein product lacks the death domain and forms a heterotrimer complex with wildtype DR3 that dominant-negatively inhibits ligand-induced apoptosis in lymphocytes. Myelocytes from transgenic mice expressing the human DR3 variant produced soluble truncated DR3, forming a complex with TNF-like ligand 1A (TL1A), which inhibited apoptosis induction. In summary, our results reveal that a DR3 splice variant that interferes with ligand-induced T cell responses and apoptosis may contribute to RA pathogenesis.

Decoy receptor 3 down-regulates centrosomal protein 70 kDa specifically in rheumatoid synovial fibroblasts

Objectives: Decoy receptor 3 (DcR3) competitively binds to Fas ligand, lymphotoxin-related inducible ligand that competes for glycoprotein D binding to herpes virus entry mediator on T cells (LIGHT) and TNF-like ligand 1A (TL1A), thereby preventing their effects. Using a microarray assay, we previously newly identified centrosomal protein 70 kDa (CEP70) as one of the genes whose expression in fibroblast-like synoviocytes from patients with rheumatoid arthritis (RA-FLS) is reduced by DcR3. Here, we investigated the significance of DcR3 regulation of CEP70 for RA-FLS.Methods: Synovial samples were obtained from RA patients who had never been treated with biologics and from osteoarthritis (OA) patients. CEP70 mRNA expression was quantified using RT-qPCR analysis. CEP70 protein expression was assessed using immunohistochemical and western blot analyses.Results: CEP70 was expressed predominantly in the superficial lining layer in RA synovial tissue. CEP70 expression was dose-dependently downregulated by DcR3-Fc in RA-FLS but was not downregulated in OA-FLS. TL1A antibody prevented the DcR3-Fc inhibitory effects on CEP70 expression in RA-FLS.Conclusions: These results indicated that DcR3 reduces CEP70 expression in RA-FLS by binding to membrane-bound TL1A and may suppress RA-FLS proliferation. The reduction in CEP70 expression by DcR3/TL1A signaling may control the hyperplasia of RA synovium.

The relationship between the cytokines TNF and TL1A in rheumatoid arthritis

Abstract The TNF-family cytokine TL1A (TNF-like ligand 1A) signaling through its receptor DR3 (Death Receptor 3) promotes immunopathology in diverse autoimmune disease models by facilitating T cell accumulation and Innate Lymphoid Cell activation at the site of inflammation while leaving systemic immune responses unaffected. TNF, a close homolog of TL1A, is a successful therapeutic in autoimmune diseases including rheumatoid arthritis (RA) and inflammatory bowel disease (IBD). However, a significant fraction of patients do not adequately respond to TNF blockade and are in need of alternative therapies. Previous studies have reported elevated TL1A levels in serum and synovial fluid of patients with RA. Yet, how TL1A expression may be influenced by TNF, and whether blocking TL1A/DR3 interactions would be a viable treatment for RA is unknown. We found that soluble TL1A levels are specifically elevated in synovial fluid and serum from RA patients, and that TNF blockade reduces serum TL1A levels in both responders and non-responders. Additionally, in a murine model of collagen-induced arthritis, antibody blockade of TL1A reduced both clinical disease and bone destruction. To further understand the relationship between TL1A and TNF we are now utilizing the TNFDARE mouse model of spontaneous TNF driven arthritis crossed to DR3 deficient mice. By 3D micro CT imaging and cytokine analysis of the joints we will determine if the blockade of TL1A/DR3 interactions alleviates arthritis driven by excess TNF. Taken together, these studies support an investigation into TL1A blockade as a potential therapy for patients with rheumatoid arthritis.

TL1A/DR3 axis involvement in the inflammatory cytokine network during pulmonary sarcoidosis.

BackgroundTNF-like ligand 1A (TL1A), a recently recognized member of the TNF superfamily, and its death domain receptor 3 (DR3), firstly identified for their relevant role in T lymphocyte homeostasis, are now well-known mediators of several immune-inflammatory diseases, ranging from rheumatoid arthritis to inflammatory bowel diseases to psoriasis, whereas no data are available on their involvement in sarcoidosis, a multisystemic granulomatous disease where a deregulated T helper (Th)1/Th17 response takes place.MethodsIn this study, by flow cytometry, real-time PCR, confocal microscopy and immunohistochemistry analyses, TL1A and DR3 were investigated in the pulmonary cells and the peripheral blood of 43 patients affected by sarcoidosis in different phases of the disease (29 patients with active sarcoidosis, 14 with the inactive form) and in 8 control subjects.ResultsOur results demonstrated a significant higher expression, both at protein and mRNA levels, of TL1A and DR3 in pulmonary T cells and alveolar macrophages of patients with active sarcoidosis as compared to patients with the inactive form of the disease and to controls. In patients with sarcoidosis TL1A was strongly more expressed in the lung than the blood, i.e., at the site of the involved organ. Additionally, zymography assays showed that TL1A is able to increase the production of matrix metalloproteinase 9 by sarcoid alveolar macrophages characterized, in patients with the active form of the disease, by reduced mRNA levels of the tissue inhibitor of metalloproteinase (TIMP)-1.ConclusionsThese data suggest that TL1A/DR3 interactions are part of the extended and complex immune-inflammatory network that characterizes sarcoidosis during its active phase and may contribute to the pathogenesis and to the progression of the disease.

Elevated plasma levels of TL1A in newly diagnosed systemic lupus erythematosus patients.

Systemic lupus erythematosus (SLE) is an autoimmune disease. Cytokine-mediated immunity plays an important role in the pathogenesis of SLE. TNF-like ligand 1A (TL1A) belongs to the TNF superfamily of cytokines and has been found to perform significantly in autoimmune diseases, such as rheumatoid arthritis and inflammatory bowel disease. To date, no study has discussed the expression levels of TL1A in SLE. We found that plasma levels of TL1A were significantly higher in newly diagnosed SLE patients compared with controls. Correlation analysis showed that plasma levels of TL1A were positively associated with SLE disease activity index. These data indicated that TL1A may play a role in SLE and may reflect the disease activity for SLE.

TNF-like ligand 1A is associated with the pathogenesis of psoriasis vulgaris and contributes to IL-17 production in PBMCs.

TNF-like ligand 1A (TL1A), a newly identified member of the TNF superfamily, has been proved as an important mediator of inflammation and critically involved in the pathogenesis of rheumatoid arthritis and several other autoimmune diseases. The aim of our study was to determine the possible role of TL1A in the pathogenesis of psoriasis. In this study, serum levels of TL1A in patients with psoriasis vulgaris (PV) and atopic dermatitis (AD) were detected by enzyme-linked immunosorbent assay (ELISA). Then, peripheral blood mononuclear cells (PBMCs) from patients with PV were isolated, the mRNA expression of TL1A was measured by real-time quantitative PCR. The effects of TL1A on the production of T cell cytokines, such as IL-17, IFN-γ, IL-4 and IL-10 in PBMCs were determined. We demonstrated that serum TL1A levels were significantly elevated in patients with PV but not in patients with AD. Besides, the high serum TL1A levels in patients with PV decreased after treatment. PBMCs derived from psoriatic patients showed significantly increased TL1A mRNA levels. Soluble TL1A synergized with IL-23 to stimulate PBMCs from patients with PV to produce IL-17. Taken together, these findings strongly suggest that TL1A may play a role in the pathogenesis of PV.

AB0065 Elevated Serum and Synovial Fluid Levels of Tumor Necrosis Factor-Like Ligand 1A and Decoy Receptor 3 in Rheumatoid Arthritis: Induce Interleukin-17 Production

BackgroundTumor necrosis factor superfamily (TNFSF) and their receptors involve in the pathogenesis of Rheumatoid arthritis (RA) (1).TNF-like ligand 1A (TL1A), a member of the TNFSF, can be secreted by endothelial...

The biological function of membrane versus soluble TL1A (CCR3P.205)

Abstract The Tumour Necrosis Factor Superfamily (TNFSF) are an important source of costimulatory signals required for activation of T cells. The TNFSF is composed of 29 receptors and 18 ligands; one such pair is Death receptor 3 (DR3) and TNF-like ligand 1A (TL1A). Signalling via DR3 costimulates lymphocytes and polymorphysims in TL1A and DR3 have been associated with Crohn's Disease. In mice, signalling via DR3 has been shown to be required for maximal pathology in models of asthma and lupus and transgenic constitutive expression of TL1A results in an IL-13 and IL-17a driven intestinal pathology. Several TNFSF ligands, including TL1A, can be expressed on the membrane and cleaved to yield a soluble product. Some cytokines, such as TNF are active in soluble form whereas others, such as FasL, are not. The biological roles of these distinct forms of TL1A in vivo are not known. To investigate the biological function of membrane vs. soluble TL1A we used retrotransgenic technology to express cleavable vs. membrane bound TL1A throughout the murine hematopoietic system. Membrane restricted TL1A promoted a strong inflammatory pathology in both the ileum and lung. Full length TL1A expression yielded little membrane TL1A. These mice failed to develop pathology despite a greater than physiological level of TL1A in the serum. This work demonstrated that membrane restricted TL1A is a more potent ligand for DR3. We have generated membrane-restricted TL1A transgenic mice to investigate this further.

Progranulin-Derived Atsttrin Directly Binds to TNFRSF25 (DR3) and Inhibits TNF-Like Ligand 1A (TL1A) Activity

Atsttrin, a progranulin (PGRN)-derived molecule composed of three TNFR-binding domains of PGRN, binds to TNF receptors (TNFR) and is therapeutic against inflammatory arthritis. Here we screened the associations of Atsttrin and other members in TNFR subfamily, which led to the discovery of TNFRSF25 (DR3) as an additional Atsttrin-interacting member in TNFR family. Similar to TNFR1 and TNFR2, DR3 also directly bound to Atsttrin. The first three cysteine-rich domains (CRD) in the extracellular portion of DR3 were required for this interaction. Atsttrin inhibited the interaction between DR3 and its TNF-Like Ligand 1A (TL1A). In addition, Atsttrin inhibited TL1A-stimulated target gene expressions and neutralized TL1A-enhanced osteoclastogenesis in vitro. Furthermore, Atsttrin ameliorated the pathology in dextran sulfate sodium induced colitis. Taken together, these findings not only provide the new insights into Atsttrin's therapeutic action in inflammatory arthritis, but may also present Atsttrin as a novel biological agent for treating various types of diseases associated with TL1A/DR3 pathway.