Tumor Necrosis Factor Superfamily Research Articles

Recent developments in targets for ischemic foot disease.

Diabetes is a key risk factor for ischaemic foot disease, which causes pain, tissue loss, hospital admission, and major amputation. Currently, treatment focuses on revascularisation, but many patients are unsuitable for surgery and revascularisation is frequently unsuccessful. The authors describe recent research in animal models and clinical trials investigating novel medical targets for ischaemia, including theories about impaired wound healing, animal models for limb ischaemia and recent randomised controlled trials testing novel medical therapies. Novel targets identified in animal models included stimulating mobilisation of CD34+ progenitor cells through upregulating oncostatin M or microRNA-181, downregulating tumour necrosis factor superfamily member 14, or activating the Wingless pathway. Within the ischaemic limb vasculature, upregulation of apolipoprotein L domain containing 1, microRNA-130b or long noncoding RNA that enhances endothelial nitric oxide synthase expression promoted limb blood supply recovery, angiogenesis, and arteriogenesis. Similarly, administration of soluble guanylate cyclase stimulators riociguat or praliciguat or 3-ketoacyl-CoA thiolase inhibitor trimetazidine promoted blood flow recovery. Translating pre-clinical findings to patients has been challenging, mainly due to limitations in clinically translatable animal models of human disease. Promising results have been reported for administering plasmids encoding hepatocyte growth factor or intra-arterial injection of bone marrow derived cells in small clinical trials. It remains to be seen whether these high resource therapies can be developed to be widely applicable. In conclusion, an ever-expanding list of potential targets for medical revascularisation is being identified. It is hoped that through ongoing research and further larger clinical trials, these will translate into new broadly applicable therapies to improve outcomes.

Berberine might block colorectal carcinogenesis by inhibiting the regulation of B-cell function by Veillonella parvula.

Colorectal carcinogenesis and progression are related to the gut microbiota and the tumor immune microenvironment. Our previous clinical trial demonstrated that berberine (BBR) hydrochloride might reduce the recurrence and canceration of colorectal adenoma (CRA). The present study aimed to further explore the mechanism of BBR in preventing colorectal cancer (CRC). We performed metagenomics sequencing on fecal specimens obtained from the BBR intervention trial, and the differential bacteria before and after medication were validated using quantitative polymerase chain reaction. We further performed ApcMin/+ animal intervention tests, RNA sequencing, flow cytometry, immunohistochemistry, and enzyme-linked immunosorbent assays. The abundance of fecal Veillonella parvula ( V . parvula ) decreased significantly after BBR administration ( P = 0.0016) and increased through the development from CRA to CRC. Patients with CRC with a higher V. parvula abundance had worse tumor staging and a higher lymph node metastasis rate. The intestinal immune pathway of Immunoglobulin A production was activated, and the expression of TNFSF13B (Tumor necrosis factor superfamily 13b, encoding B lymphocyte stimulator [BLyS]), the representative gene of this pathway, and the genes encoding its receptors (interleukin-10 and transforming growth factor beta) were significantly upregulated. Animal experiments revealed that V. parvula promoted colorectal carcinogenesis and increased BLyS levels, while BBR reversed this effect. BBR might inhibit V. parvula and further weaken the immunomodulatory effect of B cells induced by V. parvula , thereby blocking the development of colorectal tumors. ClinicalTrials.gov, No. NCT02226185.

LIGHT (TNFSF14) promotes the differentiation of human bone marrow-derived mesenchymal stem cells into functional hepatocyte-like cells.

Liver transplantation is the most effective treatment option for patients with acute or chronic liver failure. However, the applicability and effectiveness of this modality are often limited by a shortage of donors, surgical complications, high medical costs, and the need for continuing immunosuppressive therapy. An alternative approach is liver cell transplantation. LIGHT (a member of the tumor necrosis factor superfamily) could be a promising candidate for promoting the differentiation of human bone marrow-derived mesenchymal stem cells (hBM-MSCs) into hepatocyte-like cells. In this study, we investigated the effect of LIGHT on hBM-MSC differentiation into hepatocyte-like cells. Our previous results showed that LIGHT receptor lymphotoxin-β receptor (LTβR) is constitutively expressed on the surface of hBM-MSCs. Upon treatment with recombinant human LIGHT (rhLIGHT), the phenotype of hBM-MSCs changed to round or polygonal cells. In addition, the cells exhibited high levels of hepatocyte-specific markers, including albumin, cytokeratin-18 (CK-18), CK-19, cytochrome P450 family 1 subfamily A member 1 (CYP1A1), CYP1A2, CYP3A4, SRY-box transcription factor 17 (SOX17), and forkhead box A2 (FOXA2). These results indicate that rhLIGHT enhances the differentiation of hBM-MSCs into functional hepatocyte-like cells. Furthermore, rhLIGHT-induced hepatocyte-like cells showed a higher ability to store glycogen and uptake indocyanine green compared with control cells, indicating functional progression. Additionally, treatment with rhLIGHT increased the number, viability, and proliferation of cells by inducing the S/G2/M phase and upregulating the expression of various cyclin and cyclin dependent kinase (CDK) proteins. We also found that the hepatogenic differentiation of hBM-MSCs induced by rhLIGHT was mediated by the activation of signal transducer and activator of transcription 3 (STAT3) and STAT5 pathways. Overall, our findings suggest that LIGHT plays an essential role in promoting the hepatogenic differentiation of hBM-MSCs. Hence, LIGHT may be a valuable factor for stem cell therapy.

Role of tumor necrosis factor-alpha in the central nervous system: a focus on autoimmune disorders.

Tumor necrosis factor-alpha (TNF-α) is a pleiotropic immune cytokine that belongs to the TNF superfamily of receptor ligands. The cytokine exists as either a transmembrane or a soluble molecule, and targets two distinct receptors, TNF-α receptor 1 (TNFR1) and TNF-α receptor 2 (TNFR2), which activate different signaling cascades and downstream genes. TNF-α cellular responses depend on its molecular form, targeted receptor, and concentration levels. TNF-α plays a multifaceted role in normal physiology that is highly relevant to human health and disease. In the central nervous system (CNS), this cytokine regulates homeostatic functions, such as neurogenesis, myelination, blood-brain barrier permeability and synaptic plasticity. However, it can also potentiate neuronal excitotoxicity and CNS inflammation. The pleiotropism of TNF-α and its various roles in the CNS, whether homeostatic or deleterious, only emphasizes the functional complexity of this cytokine. Anti-TNF-α therapy has demonstrated effectiveness in treating various autoimmune inflammatory diseases and has emerged as a significant treatment option for CNS autoimmune diseases. Nevertheless, it is crucial to recognize that the effects of this therapeutic target are diverse and complex. Contrary to initial expectations, anti-TNF-α therapy has been found to have detrimental effects in multiple sclerosis. This article focuses on describing the various roles, both physiological and pathological, of TNF-α in the CNS. Additionally, it discusses the specific disease processes that are dependent or regulated by TNF-α and the rationale of its use as a therapeutic target.

LIGHT/TNFSF14 promotes CAR-T cell trafficking and cytotoxicity through reversing immunosuppressive tumor microenvironment

Tertiary lymphoid structures (TLSs) in tumor tissues facilitate immune cell trafficking and cytotoxicity, which benefits survival and favorable responses in immune therapy. Here, we observed a high correlation of tumor necrosis factor superfamily member 14 (LIGHT) expression with TLS signature genes, which are all markers for immune cell accumulation and better prognosis, through retrieving RNA sequencing (RNA-seq) data from patients with cancer, suggesting the potential of LIGHT in reconstituting a high immune-infiltrated tumor microenvironment. Accordingly, LIGHT co-expressed chimeric antigen receptor T (LIGHT CAR-T) cells not only showed enhanced cytotoxicity and cytokine production but also improved CCL19 and CCL21 expression by surrounding cells. And the supernatant of LIGHT CAR-T cells promoted Tcell migration in a paracrine manner. Furthermore, LIGHT CAR-T cells showed superior anti-tumor efficacy and improved infiltration in comparison with conventional CAR-T cells in immunodeficient NSG mice. Accordingly, murine LIGHT-OT-1 Tcells normalized tumor blood vessels and enforced intratumoral lymphoid structures in C57BL/6 syngeneic tumor mouse models, implying the potential of LIGHT CAR-T in clinical application. Taken together, our data revealed a straightforward strategy to optimize trafficking and cytotoxicity of CAR-T cells by redirecting TLSs through LIGHT expression, which has great potential to expand and optimize the application of CAR-T therapy in solid tumors.

TNF superfamily control of tissue remodeling and fibrosis.

Fibrosis is the result of extracellular matrix protein deposition and remains a leading cause of death in USA. Despite major advances in recent years, there remains an unmet need to develop therapeutic options that can effectively degrade or reverse fibrosis. The tumor necrosis super family (TNFSF) members, previously studied for their roles in inflammation and cell death, now represent attractive therapeutic targets for fibrotic diseases. In this review, we will summarize select TNFSF and their involvement in fibrosis of the lungs, the heart, the skin, the gastrointestinal tract, the kidney, and the liver. We will emphasize their direct activity on epithelial cells, fibroblasts, and smooth muscle cells. We will further report on major clinical trials targeting these ligands. Whether in isolation or in combination with other anti-TNFSF member or treatment, targeting this superfamily remains key to improve efficacy and selectivity of currently available therapies for fibrosis.

Genome-wide identification of TNF receptor-associated factors in Japanese flounder (Paralichthys olivaceus) and functional analysis of resistance to temperature and Edwardsiella tarda stress.

Tumor necrosis factor receptor-associated factors (TRAFs), as the signaling mediators of the tumor necrosis factor (TNFR) superfamily, toll-like receptors (TLR) and interleukin-1 receptor (IL-1R) superfamily, can activate downstream signal transduction pathways and play an important role in the body's immune process. In this study, six TRAF genes, namely PoTRAF2a, PoTRAF2b, PoTRAF3, PoTRAF4, PoTRAF6 and PoTRAF7, were identified and annotated in Japanese flounder by using bioinformatics methods. Phylogenetic analysis confirmed that TRAF genes can be divided into seven groups. Analysis of motif composition and gene structure demonstrated that all PoTRAF members were evolutionarily conserved. The expression patterns of PoTRAF genes were then further investigated in six different developmental stages and eleven tissues of healthy fish, and it was found that there were spatial and tissue specificities among the members. To investigate the immune response of Japanese flounder to abiotic and biotic stresses, we further analyzed the expression profile of PoTRAFs after temperature stress and pathogen challenge. The result showed that PoTRAF3 and PoTRAF4 were observably differentially expressed under temperature stress, indicating that they were involved in the immune response after temperature stress. The expression of PoTRAF2a, PoTRAF2b and PoTRAF4 was significantly different after E. tarda infection, suggesting that they might have antibacterial effects. These results would help to clarify the molecular roles of PoTRAF genes in the regulation of immune and inflammatory responses in Japanese flounder.

Exploration of the association between the single-nucleotide polymorphism of co-stimulatory system and rheumatoid arthritis.

The human leukocyte antigen (HLA) has been linked to the majority of autoimmune diseases (ADs). However, non-HLA genes may be risk factors for ADs. A number of genes encoding proteins involved in regulating T-cell and B-cell function have been identified as rheumatoid arthritis (RA) susceptibility genes. In this study, we investigated the association between RA and single-nucleotide polymorphisms (SNPs) of co-stimulatory or co-inhibitory molecules in 124 RA cases and 100 healthy controls without immune-related diseases [including tumor necrosis factor superfamily member 4 (TNFSF4), CD28, cytotoxic T-lymphocyte-associated protein 4 (CTLA4), and programmed cell death protein 1 (PDCD1)]. The results showed that there were 13 SNPs associated with RA, including rs181758110 of TNFSF4 (CC vs. CT, p = 0.038); rs3181096 of CD28 (TT vs. CC + CT, p = 0.035; CC vs. TT, p = 0.047); rs11571315 (TT vs. CT, p = 0.045), rs733618 (CC vs. TT + CT, p = 0.043), rs4553808 (AA vs. AG vs. GG, p = 0.035), rs11571316 (GG vs. AG vs. AA, p = 0.048; GG vs. AG + AA, p = 0.026; GG vs. AG, p = 0.014), rs16840252 (CC vs. CT vs. TT, p = 0.007; CC vs. CT, p = 0.011), rs5742909 (CC vs. CT vs. TT, p = 0.040), and rs11571319 of CTLA4 (GG vs. AG vs. AA, p < 0.001; GG vs. AG + AA, p = 0.048; AA vs. GG + AG, p = 0.001; GG vs. AA, p = 0.008; GG vs. AG, p ≤ 0.001); and rs10204525 (TT vs. CT + CC, p = 0.024; TT vs. CT, p = 0.021), rs2227982 (AA vs. GG, p = 0.047), rs36084323 (TT vs. CT vs. CC, p = 0.022; TT vs. CT + CC, p = 0.013; CC vs. TT + CT, p = 0.048; TT vs. CC, p = 0.008), and rs5839828 of PDCD1 (DEL vs. DEL/G vs. GG, p = 0.014; DEL vs. DEL/G + GG, p = 0.014; GG vs. DEL + DEL/G, p = 0.025; DEL vs. GG, p = 0.007). Consequently, these SNPs may play an important role in immune regulation, and further research into the role of these SNPs of immune regulatory genes in the pathogenesis of RA is required.

#3666 THE PROTECTIVE ROLE OF BUTYRATE IN KIDNEY INJURY

Abstract Background and Aims Butyrate is a well-known short-chain fatty acid (SCFAs) produced by the microbial fermentation of indigestible fibers. It contributes to colon homeostasis and controls inflammatory responses and homeostasis in other tissues. It is thought to play an important role in the pathogenesis of kidney disease and contributes to the connections between diet, gut microbiota, and kidney disease. However, a detailed characterization of its function in kidney injury is required. TWEAK is involved in tissue injury, driving inflammation, proliferation, fibrosis and inducing death of renal tubular epithelial cells under certain microenvironmental conditions, such a proinflammatory milieu composed of TNFα and INFγ. It downregulates nephroprotector factors and upregulate the expression of inflammatory markers. Method A dose-response curve evaluated cell viability in murine tubular cells (MCT) at different butyrate concentrations using MTT assay. For this, cells were pre-treated with butyrate 0.5, 1 or 5 mM for one hour. After that, they were treated either with TWEAK (tumor necrosis factor-like weak inducer of apoptosis), a member of the TNF superfamily or TTI (TWEAK 100 ng/mL, TNfα 30 ng/mL and INFΓ 30 UI/mL). Through RT-PCR and Western blotting, mRNA and protein levels of various markers were quantified at 3, 6 and 24 h. Results were validated in a kidney-on-a-chip, a microphysiological system that intends to recapitulate key functional characteristics of the kidney, among them, the dynamic conditions in which cells are cultured, mimicking the fluid flows that occurs in the body and with the benefit of representing an alternative to animal testing. It is composed of a hollow fiber membrane, precoated with L-DOPA (2 mg/mL) and collagen IV (1 mg/mL) seeded with human conditionally immortalized proximal tubule epithelial cells (cipTEC-OAT1). After ten days, cells were exposed to butyrate (1 mM) in the basolateral compartment and TWEAK (100 ng/mL) in the apical compartment for 24 h. Cell toxicity, cell viability and cell permeability were measured at 24 h through LDH release, and PrestoBlue and FITC-Inulin assays, respectively. Cells and supernatant were collected to perform RT-PCR and ELISA for relevant markers. Results When MCT cells were pre-treated with butyrate and then injured either with TWEAK or TTI (TWEAK, TNF-α, IFN-Γ), the expression of klotho, a nephroprotector and anti-aging gene, and peroxisome proliferator-activated receptor Γ coactivator-1α (PGC-1α), a transcription factor that promotes mitochondrial biogenesis, were preserved, as opposed to decreased by cytokines only. Moreover, cells pre-treated with butyrate had decreased expression of inflammatory markers such as MCP1 as compared to increased expression upon cytokine stimulation. In the kidney-on-a-chip, cell viability was reduced after exposure to TWEAK compared to the cells treated only with butyrate, while cells treated with butyrate and TWEAK had lower toxicity as assessed by LDH release. Furthermore, results for Klotho, PGC-1α and the inflammation markers MCP1 and IL6 were aligned with those in MCT cells. Conclusion In summary, in-vitro, butyrate prevents injury caused by TWEAK, preserves protective factors such as the anti-aging factor Klotho and the master regulator of mitochondrial biogenesis PGC-1α and decreases inflammation. Furthermore, these results were validated in a kidney-on-a-chip microphysiological system. Characterization of the mechanism behind the protection of butyrate for kidney injury is ongoing.

Dynamic Profiling of the Immune Tumor Microenvironment in Locally Advanced Gastric Cancer Treated with Perioperative Chemotherapy

Introduction: In locally advanced gastric cancer (GC), FLOT represents the standard perioperative regimen and combination with immunotherapy is under investigation. However, the role of immune tumor microenvironment (TME) is poorly recognized in this setting. We aimed to study TME characteristics and dynamics during FLOT. Methods: Paired biopsy (PRE) and surgical (POST) samples of 25 patients treated with FLOT were prospectively analyzed. After collection of clinic-pathological data, NanoString analyses were performed. The primary objective of the study was to assess the changes induced by chemotherapy in POST compared to PRE samples. Results: The unsupervised hierarchical method analysis clearly distinguished PRE and POST samples, even though some cases showed high immune gene expression at baseline. When POST samples were compared with PRE, a differential expression in hyper-expressed gene sets related to cytotoxicity, T-cell functions, complement system, tumor necrosis factor superfamily, cell cycle, and regulation was recognized. Downstaging of the primary tumor (T-regression, measured by pathologic compared to clinical T stage) was the covariate most frequently associated with these changes. Using the immune cell profiling, cases with T-regression reported a significant increase of T, CD8+ T and B cells and a decrease in mast cells, while nonresponders demonstrated an increase of T, B, cytotoxic, and mast cells. Conclusion: Our analysis shows that FLOT significantly influences immune TME of GC. While relevant modifications preferentially occur in tumors showing primary tumor regression, response to treatment seems to be associated with a specific immune profile.

Interleukin-24-mediated antitumor effects against human glioblastoma via upregulation of P38 MAPK and endogenous TRAIL-induced apoptosis and LC3-II activation-dependent autophagy

BackgroundMelanoma differentiation-associated gene 7 (Mda-7) encodes IL-24, which can induce apoptosis in cancer cells. A novel gene therapy approach to treat deadly brain tumors, recombinant mda-7 adenovirus (Ad/mda-7) efficiently kills glioma cells. In this study, we investigated the factors affecting cell survival and apoptosis and autophagy mechanisms that destroy glioma cells by Ad/IL-24.MethodsHuman glioblastoma U87 cell line was exposed to a multiplicity of infections of Ad/IL-24. Antitumor activities of Ad/IL-24 were assessed by cell proliferation (MTT) and lactate dehydrogenase (LDH) release analysis. Using flow cytometry, cell cycle arrest and apoptosis were investigated. Using the ELISA method, the tumor necrosis factor (TNF-α) level was determined as an apoptosis-promoting factor and Survivin level as an anti-apoptotic factor. The expression levels of TNF-related apoptosis inducing ligand(TRAIL) and P38 MAPK genes were assessed by the Reverse transcription-quantitative polymerase chain reaction(RT‑qPCR) method. The expression levels of caspase-3 and protein light chain 3-II (LC3-II) proteins were analyzed by flow cytometry as intervening factors in the processes of apoptosis and autophagy in the cell death signaling pathway, respectively.ResultsThe present findings demonstrated that transduction of IL-24 inhibited cell proliferation and induced cell cycle arrest and cell apoptosis in glioblastoma. Compared with cells of the control groups, Ad/IL24-infected U87 cells exhibited significantly increased elevated caspase-3, and TNF-α levels, while the survivin expression was decreased. TRAIL was shown to be upregulated in tumor cells after Ad/IL-24 infection and studies of the apoptotic cascade regulators indicate that Ad/IL-24 could further enhance the activation of apoptosis through the TNF family of death receptors. In the current study, we demonstrate that P38 MAPK is significantly activated by IL-24 expression. In addition, the overexpression of mda-7/IL-24 in GBM cells induced autophagy, which was triggered by the upregulation of LC3-II.ConclusionsOur study demonstrates the antitumor effect of IL-24 on glioblastoma and may be a promising therapeutic approach for GBM cancer gene therapy.

Detection effectiveness of immune-related gene mutations in lung adenocarcinoma by circulating tumor DNA.

e20580 Background: Lung adenocarcinomas (LUAD) is the major pathological subtype of lung cancer with a poor prognosis. Tumor development and progression are significantly influenced by immune microenvironment. However, immune-related gene alterations have not been utilized in prognostic evaluation frequently. Circulating tumor DNA (ctDNA) provides a non-invasive approach to cancer diagnosis and prognosis. It is possible to find immune-related biomarkers that may be used to predict clinical outcomes and evaluate the effectiveness of ctDNA for the detection of immune-related gene mutations in LUAD. Methods: Immunologically relevant genes were downloaded from ImmPort, including chemokines (n = 102), cytokine receptors (n = 307), cytokines (n = 456), interferons (n = 17), interleukins receptors (n = 42), interleukins (n = 47), TGF-β family (n = 33) and TNF family (n = 12). Clinical and genetic mutation data of 604 LUAD samples were obtained from cBioPortal. The Kaplan-Meier method of survival analysis was used to estimate the overall survival (OS) of the published LUAD data set. 1837 LUAD patients collected both tumor tissue and blood samples were screened from the HapLab database (HaploX, Shenzhen, China). Results: OS analysis had been processed in each immune-related gene set and gene receptively. Only patients with cytokine receptor mutations showed a poor prognosis compared with the wild-type (log-rank test, p-value = 0.027). OS did not differ statistically significantly in patients with or without alterations in any other immune-related gene sets or individual genes. Protein-coding mutations of 32 cytokine receptor genes were found in 1290 LUAD tumor tissue samples from HapLab database. 93.75% (30/32) genes were observed mutations in paired plasma ctDNA results, and the minimum variant allele frequency (VAF) was 0.04%. 243 alterations in cytokine receptor genes were only detected in 54 peripheral blood samples. The overall sensitivity and specificity were 91.09% and 40.05% in blood ctDNA assay. Conclusions: The mutational status of cytokine receptor genes in LUAD is significantly associated with long-term OS. The presence of tumor DNA in the blood showed high diagnostic accuracy for detecting cytokine receptor mutations in LUAD patients. Circulating tumor DNA-based liquid biopsy offers LUAD patients a non-invasive prognostic assessment method based on immune-related gene mutation screening. [Table: see text]

A human model of asthma exacerbation reveals transcriptional programs and cell circuits specific to allergic asthma.

Asthma is a chronic disease most commonly associated with allergy and type 2 inflammation. However, the mechanisms that link airway inflammation to the structural changes that define asthma are incompletely understood. Using a human model of allergen-induced asthma exacerbation, we compared the lower airway mucosa in allergic asthmatics and allergic non-asthmatic controls using single-cell RNA sequencing. In response to allergen, the asthmatic airway epithelium was highly dynamic and up-regulated genes involved in matrix degradation, mucus metaplasia, and glycolysis while failing to induce injury-repair and antioxidant pathways observed in controls. IL9-expressing pathogenic TH2 cells were specific to asthmatic airways and were only observed after allergen challenge. Additionally, conventional type 2 dendritic cells (DC2 that express CD1C) and CCR2-expressing monocyte-derived cells (MCs) were uniquely enriched in asthmatics after allergen, with up-regulation of genes that sustain type 2 inflammation and promote pathologic airway remodeling. In contrast, allergic controls were enriched for macrophage-like MCs that up-regulated tissue repair programs after allergen challenge, suggesting that these populations may protect against asthmatic airway remodeling. Cellular interaction analyses revealed a TH2-mononuclear phagocyte-basal cell interactome unique to asthmatics. These pathogenic cellular circuits were characterized by type 2 programming of immune and structural cells and additional pathways that may sustain and amplify type 2 signals, including TNF family signaling, altered cellular metabolism, failure to engage antioxidant responses, and loss of growth factor signaling. Our findings therefore suggest that pathogenic effector circuits and the absence of proresolution programs drive structural airway disease in response to type 2 inflammation.

Distinct immune modulatory roles of regulatory T cells in gut versus joint inflammation in TNF-driven spondyloarthritis

ObjectivesGut and joint inflammation commonly co-occur in spondyloarthritis (SpA) which strongly restricts therapeutic modalities. The immunobiology underlying differences between gut and joint immune regulation, however, is poorly understood. We therefore...

The Role of TRAIL in Apoptosis and Immunosurveillance in Cancer

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a member of the TNF superfamily that selectively induces apoptosis in tumor cells without harming normal cells, making it an attractive agent for cancer therapy. TRAIL induces apoptosis by binding to and activating its death receptors DR4 and DR5. Several TRAIL-based treatments have been developed, including recombinant forms of TRAIL and its death receptor agonist antibodies, but the efficacy of TRAIL-based therapies in clinical trials is modest. In addition to inducing cancer cell apoptosis, TRAIL is expressed in immune cells and plays a critical role in tumor surveillance. Emerging evidence indicates that the TRAIL pathway may interact with immune checkpoint proteins, including programmed death-ligand 1 (PD-L1), to modulate PD-L1-based tumor immunotherapies. Therefore, understanding the interaction between TRAIL and the immune checkpoint PD-L1 will lead to the development of new strategies to improve TRAIL- and PD-L1-based therapies. This review discusses recent findings on TRAIL-based therapy, resistance, and its involvement in tumor immunosurveillance.

Tumor necrosis factor superfamily in multiple sclerosis: from pathology to therapeutic implications

Tumor necrosis factor (TNF) is a key player in multiple sclerosis pathology. TNF signaling is dually regulated by antagonist groups of actors: TNFR1, mediating proinflammatory effects and synaptopathy, CD40L-CD40 dyad, crucial for blood-brain barrier breakdown and facilitation of recruitment of inflammatory cells in the central nervous system, and TNFR2, promoting neuroprotective and reparative functions. A promising therapeutic approach in multiple sclerosis is represented by selective TNFR1 antagonists and TNFR2 agonists, possibly in combination. TNFR2 agonists could exert both central effects such as remyelination, reduction of glutamatergic excitotoxicity, and peripheral immunomodulation by enhancing T cells (Treg) activity. On the other side, the potential therapeutic role of platelet and CD40L-CD40 dyad inhibition could be beneficial to preserve blood-brain barrier integrity and thereby dampen neuroinflammation.

TL1A control of eczema and psoriasis

Abstract Psoriasis is a Th17-induced dermatitis, characterized by epidermal thickening. Psoriasis increases the risk of developing arthritis and cardiovascular-related morbidities, hence the need to stop its progression early. Why the disease is patchy, and what activates the keratinocytes in the psoriatic plaques driving a Th17-type inflammation, remain unknown. Chronic exposure to imiquimod (IMQ) drives psoriasis in mice reminiscent of human disease. We have preliminary data implicating the TNFSF (tumor necrosis factor superfamily) member TL1A (tumor necrosis factor-like cytokine 1A) in psoriasis. Our loss of function studies show that the genetic deletion of TL1A receptor, protects from IMQ-induced psoriasis. Further, TL1A is known to be enriched in the psoriatic lesions and serum of psoriatic patients. These findings suggest that TL1A may play a central role in the development and maintenance of psoriasis. Therefore, targeting TL1A could be beneficial to treat Psoriasis.

Shedding LIGHT and TL1A on Pulmonary Fibrosis

Abstract Currently, anti-inflammatory drugs fail to reduce pulmonary fibrosis (PF) and tissue remodeling in the clinic. Despite the advancements made in understanding the molecular pathways driving PF, there is still an unmet need to develop innovative and effective anti-fibrotic drugs. Our lab has identified two novel mediators of fibrosis belonging to the tumor necrosis factor superfamily (TNFSF), LIGHT (TNFSF14) and TL1A (TNFSF15). Using a well characterized mouse model of PF driven by bleomycin, we showed that blocking LIGHT or TL1A signaling in isolation, by genetic ablation or antibody-mediated neutralization, significantly reduces PF. In gain of function studies, the in vivo administration of LIGHT or TL1A in isolation recapitulated fibrosis symptoms reminiscent of human disease. Furthermore, our data suggest that LIGHT promotes thymic stromal lymphopoietin (TLSP) expression by epithelial cells, whereas TL1A activates fibroblasts to promote periostin expression. Both TSLP and periostin are drivers of PF. Importantly, we observed an upregulation of LIGHT and DR3 (the receptor for TL1A) in human lung biopsies of patients suffering SSc and IPF. We have found that LIGHT and TL1A can drive fibrosis independently of one another and that the in vivo co-administration of these TNFSF members synergize to maximize inflammation and collagen deposition. Using antagonistic fusion proteins to neutralize LIGHT and TL1A signaling, we will monitor PF in vivo and check whether greater efficacy is achieved when LIGHT and TL1A are targeted concomitantly post-disease onset. The relevance of this work on PF associated with ILDs in humans is tremendous.

Abstract 443: BAFF Neutralization Impairs The Regression Of Insulin Resistance In Diabetic Mice By Modulating The Innate Immune Response

Adults with type 2 diabetes have a two-to-three-fold increased risk of cardiovascular diseases. B cell activating factor (BAFF), a tumor necrosis factor superfamily member, is implicated both in diabetes and cardiovascular diseases, and hence a therapeutic target of interest. High levels of BAFF are known to promote autoantibody synthesis and autoimmune diseases. We examined if BAFF neutralization with an anti-BAFF antibody improves glucose intolerance in a model of regression of insulin resistance in diabetic mice. Male C57BL/6J mice were fed a high-fat diet (HFD) for 12 weeks and segregated into two groups based on their glucose intolerance determined by a glucose tolerance test. Each group was simultaneously switched from HFD to a normal chow diet and received injections of anti-BAFF or an isotype control antibody every 2 nd week for a total of 6 weeks. As expected, body weights decreased in both groups parallel with the increase in insulin sensitivity. Unexpectedly, the BAFF-neutralized mice had impaired regression of insulin resistance compared to the control mice. Extensive cellular phenotyping of immune cells indicated systemic depletion of only the B2 cells and lower levels of circulating autoantibodies in the BAFF-neutralized mice. Gonadal white adipose tissue (gWAT) was the primary source of BAFF, and no differences in the M1 and M2 macrophages, eosinophils, natural killer cells, helper T cells, and cytotoxic T cell populations were found. RNA sequencing analysis of stromal vascular fraction from gWAT revealed impaired B cell receptor signaling, immunoglobulin production, complement activation, and phagocytosis pathways in the BAFF-neutralized mice. In this line, (i) an increased number of dead adipocytes, (ii) decreased levels of IgG2b and IgM, (iii) increased citrullinated histone H3, neutrophils, and DNA extracellular traps were found in the gWAT of BAFF-neutralized mice. These results suggest attenuated humoral response and a dominant and harmful role of innate response in the gWAT following BAFF neutralization in late-stage obesity. Since anti-BAFF biologics are approved for the treatment of lupus patients, our results highlight the need for further studies on the role of BAFF in late-stage obesity and diabetes.

The TNF superfamily cytokine receptor Death Receptor 3 is a costimulatory molecule for iNKT cells

Abstract Invariant NKT (iNKT) cells are a small population of thymus-generated T lymphocytes with innate-like phenotype and function that play a disproportionally important role in immune regulation and surveillance. iNKT cells are generated upon strong agonistic TCR signaling by glycolipid-loaded CD1d molecules, which differs from conventional T cells that are positively selected by weak TCR engagement with peptide-loaded MHC molecules. Whether iNKT cells are also distinct in their costimulatory requirement, however, has remained largely unresolved. Here, we report that the TNF superfamily receptor death receptor 3 (DR3) plays a previously unappreciated costimulatory role in peripheral iNKT cell activation. We found that the co-injection of agonistic anti-DR3 antibodies significantly augmented the activation and proliferation of mature iNKT cells in α-GalCer injected mice. Moreover, iNKT cells of α-GalCer and anti-DR3 co-injected mice dramatically increased their expression of proinflammatory cytokines, resulting in severe thymic atrophy. The DR3 costimulatory effect was strictly dependent on iNKT cells, because iNKT-deficient Traj18−/−mice were refractory to α-GalCer and anti-DR3 costimulation-induced inflammation. Because DR3 ligation alone did not suffice to activate iNKT cells, and DR3 exerted its effects only in the context of TCR costimulation, these results strongly support DR3 being a new bona fidecostimulatory molecule for iNKT cells. Considering the interest in utilizing iNKT cells in adoptive T cell therapies and as anti-tumor bioreagents, employing DR3 as a tool to boost iNKT cell immunity will open new venues in translational and clinical research. This work was supported by the Intramural Research Program of the NIH, National Cancer Institute, Center for Cancer Research.