Glucocorticoid-induced Tumor Necrosis Factor Receptor Research Articles

A GITRL-mTORC1-GM-CSF Positive Loop Promotes Pathogenic Th17 Response in Primary Sjögren Syndrome.

Glucocorticoid-induced tumor necrosis factor receptor superfamily-related protein (GITR), with its ligand (GITRL), plays an important role in CD4+ T cell-mediated autoimmunity. This study aimed to investigate the underlying mechanisms of GITRL in primary Sjögren syndrome (pSS). Patients with pSS and healthy controls were recruited. Serum GITRL and Th17-related cytokines were determined. RNA sequencing was performed to decipher key signal pathways. Nonobese diabetes (NOD) mice were adopted as experimental Sjögren models and recombinant adeno-associated virus (rAAV) transduction was conducted to verify the therapeutic potentials of targeting GITRL in vivo. Serum GITRL was significantly higher in patients with pSS and showed a positive correlation with leukopenia, thrombocytopenia, autoantibodies, lung involvement, and disease activity. Serum GITRL was correlated with Th17-related cytokines. GITRL promoted the expansion of Th17 and Th17.1 cells. Expansion of granulocyte-macrophage colony-stimulating factor positive (GM-CSF+) CD4+ T cells induced by GITRL could be inhibited by blockade of GITRL. Moreover, GM-CSF could stimulate GITRL expression on monocytes. RNA sequencing revealed mammalian target of rapamycin complexes 1 (mTORC1) might be the key modulator. The increased phosphorylation of S6 and STAT3 and the expansion of Th17 and Th17.1 cells induced by GITRL were effectively inhibited by rapamycin, suggesting a GITRL-mTORC1-GM-CSF positive loop in pathogenic Th17 response in pSS. Administration of an rAAV vector expressing short hairpin RNA targeting GITRL alleviated disease progression in NOD mice. Our results identified the pathogenic role of GITRL in exacerbating disease activity and promoting pathogenic Th17 response in pSS through a GITRL-mTORC1-GM-CSF loop. These findings suggest GITRL might be a promising therapeutic target in the treatment of pSS.

Expression patterns of novel immunotherapy targets in intermediate- and high-grade lung neuroendocrine neoplasms

BackgroundAdvancements in immunotherapeutic approaches only had a modest impact on the therapy of lung neuroendocrine neoplasms (LNENs). Our multicenter study aimed to investigate the expression patterns of novel immunotherapy targets in intermediate- and high-grade LNENs.MethodsThe expressions of V-domain Ig suppressor of T cell activation (VISTA), OX40L, Glucocorticoid-induced TNF receptor (GITR), and T cell immunoglobulin and mucin domain 3 (TIM3) proteins were measured by immunohistochemistry in surgically resected tumor samples of 26 atypical carcinoid (AC), 49 large cell neuroendocrine lung cancer (LCNEC), and 66 small cell lung cancer (SCLC) patients. Tumor and immune cells were separately scored.ResultsTumor cell TIM3 expression was the highest in ACs (p < 0.001), whereas elevated tumor cell GITR levels were characteristic for both ACs and SCLCs (p < 0.001 and p = 0.011, respectively). OX40L expression of tumor cells was considerably lower in ACs (vs. SCLCs; p < 0.001). Tumor cell VISTA expression was consistently low in LNENs, with no significant differences across histological subtypes. ACs were the least immunogenic tumors concerning immune cell abundance (p < 0.001). Immune cell VISTA and GITR expressions were also significantly lower in these intermediate-grade malignancies than in SCLCs or in LCNECs. Immune cell TIM3 and GITR expressions were associated with borderline prognostic significance in our multivariate model (p = 0.057 and p = 0.071, respectively).ConclusionsLNEN subtypes have characteristic and widely divergent VISTA, OX40L, GITR, and TIM3 protein expressions. By shedding light on the different expression patterns of these immunotherapy targets, the current multicenter study provides support for the future implementation of novel immunotherapeutic approaches.

Macrophage-enriched Sectm1a promotes efficient efferocytosis to attenuate ischemia/reperfusion-induced cardiac injury.

Efficient clearance and degradation of apoptotic cardiomyocytes by macrophages (collectively termed efferocytosis) is critical for inflammation resolution and restoration of cardiac function after myocardial ischemia/reperfusion (I/R). Here, we define secreted and transmembrane protein 1a (Sectm1a), a cardiac macrophage-enriched gene, as a modulator of macrophage efferocytosis in I/R-injured hearts. Upon myocardial I/R, Sectm1a-KO mice exhibited impaired macrophage efferocytosis, leading to massive accumulation of apoptotic cardiomyocytes, cardiac inflammation, fibrosis, and consequently, exaggerated cardiac dysfunction. By contrast, therapeutic administration of recombinant SECTM1A protein significantly enhanced macrophage efferocytosis and improved cardiac function. Mechanistically, SECTM1A could elicit autocrine effects on the activation of glucocorticoid-induced TNF receptor (GITR) at the surface of macrophages, leading to the upregulation of liver X receptor α (LXRα) and its downstream efferocytosis-related genes and lysosomal enzyme genes. Our study suggests that Sectm1a-mediated activation of the Gitr/LXRα axis could be a promising approach to enhance macrophage efferocytosis for the treatment of myocardial I/R injury.

GITRL impairs hepatocyte repopulation by liver progenitor cells to aggravate inflammation and fibrosis by GITR+CD8+ T lymphocytes in CDE Mice

As an alternative pathway for liver regeneration, liver progenitor cells and their derived ductular reaction cells increase during the progression of many chronic liver diseases. However, the mechanism underlying their hepatocyte repopulation after liver injury remains unknown. Here, we conducted progenitor cell lineage tracing in mice and found that fewer than 2% of hepatocytes were derived from liver progenitor cells after 9 weeks of injury with a choline-deficient diet supplemented with ethionine (CDE), and this percentage increased approximately three-fold after 3 weeks of recovery. We also found that the proportion of liver progenitor cells double positive for the ligand of glucocorticoid-induced tumour necrosis factor receptor (GITRL, also called Tnfsf18) and SRY-related HMG box transcription 9 (Sox9) among nonparenchymal cells increased time-dependently upon CDE injury and reduced after recovery. When GITRL was conditionally knocked out from hepatic progenitor cells, its expression in nonparenchymal cells was downregulated by approximately fifty percent, and hepatocyte repopulation increased by approximately three folds. Simultaneously, conditional knockout of GITRL reduced the proportion of liver-infiltrating CD8+ T lymphocytes and glucocorticoid-induced tumour necrosis factor receptor (GITR)-positive CD8+ T lymphocytes. Mechanistically, GITRL stimulated cell proliferation but suppressed the differentiation of liver progenitor organoids into hepatocytes, and CD8+ T cells further reduced their hepatocyte differentiation by downregulating the Wnt/β-catenin pathway. Therefore, GITRL expressed by liver progenitor cells impairs hepatocyte differentiation, thus hindering progenitor cell-mediated liver regeneration.

Glucocorticoid-induced TNF receptor family-related protein functions as a costimulatory molecule for murine eosinophils.

Eosinophils are typical effector cells associated with type 2 immune responses and play key roles in the pathogenesis of allergic diseases. These cells are activated by various stimuli, such as cytokines, chemokines, and growth factors, but the regulatory mechanisms of eosinophil effector functions remain unclear. Glucocorticoid-induced tumor necrosis factor receptor family-related protein (GITR), a transmembrane protein belonging to the tumor necrosis factor (TNF) receptor superfamily, is a well-known regulatory molecule for T cell activation. Here, we show that GITR is also constitutively expressed on eosinophils and functions as a costimulatory molecule for these cells. Although degranulation was unaffected by GITR engagement of murine bone marrow-derived eosinophils, secretion of inflammatory cytokines such as interleukin (IL)-4, IL-6, and IL-13 from IL-33-activated bone marrow-derived eosinophils was augmented by anti-mouse GITR agonistic antibody (DTA-1). In conclusion, our results provide a new regulatory pathway of cytokine secretion from eosinophils in which GITR functions as a costimulatory molecule.

Analysis of Single-Cell Transcriptome and Surface Protein Expression in Ankylosing Spondylitis Identifies OX40-Positive and Glucocorticoid-Induced Tumor Necrosis Factor Receptor-Positive Pathogenic Th17 Cells.

To demonstrate the immune landscape of blood and synovial cells in the setting of ankylosing spondylitis (AS) through the analysis of both single-cell transcriptome and surface protein expression, and to unveil the molecular characteristics of pathogenic Th17 cells. This study included 40 individuals with active AS, 20 individuals with stable AS, 40 patients with active rheumatoid arthritis, and 20 healthy controls. Surface phenotype and intracellular staining were assessed using flow cytometry after peripheral blood mononuclear cells and synovial fluid mononuclear cells were stimulated with T cell receptor. Single-cell transcriptomes of 6 patients with active AS were studied along with cellular indexing of transcriptomes and epitopes by sequencing. We also assessed the outcome of targeting OX40 and glucocorticoid-induced tumor necrosis factor receptor (GITR) on the surface of Th17 cells in a mouse model of curdlan-injected SKG mice in which anti-GITR ligand and/or anti-OX40 ligand were used. We identified pathogenic Th17 cells as polyfunctional interleukin-17A (IL-17A)- and interferon-γ (IFNγ)-producing memory CD4+ T cells, with clinically supportive evidence for their pathogenic roles at sites of inflammation in AS. Transcriptome and flow cytometric analyses revealed that the coexpression of TNFRSF4 (OX40) and TNFRSF18 (GITR) is increased in pathogenic Th17 cells. Suppression of ligand receptor interactions in vivo through OX40 and GITR effectively suppressed clinical arthritis and decreased pathogenic Th17 cells in the curdlan-injected SKG mouse model. Our results have implications for the understanding of pathogenic Th17 cells in AS patients and suggest potential therapeutic targets.

Targeting immune checkpoints in anti-neutrophil cytoplasmic antibodies associated vasculitis: the potential therapeutic targets in the future.

Anti-neutrophil cytoplasmic autoantibodies (ANCA) associated vasculitis (AAV) is a necrotizing vasculitis mainly involving small blood vessels. It is demonstrated that T cells are important in the pathogenesis of AAV, including regulatory T cells (Treg) and helper T cells (Th), especially Th2, Th17, and follicular Th cells (Tfh). In addition, the exhaustion of T cells predicted the favorable prognosis of AAV. The immune checkpoints (ICs) consist of a group of co-stimulatory and co-inhibitory molecules expressed on the surface of T cells, which maintains a balance between the activation and exhaustion of T cells. CD28, inducible T-cell co-stimulator (ICOS), OX40, CD40L, glucocorticoid induced tumor necrosis factor receptor (GITR), and CD137 are the common co-stimulatory molecules, while the programmed cell death 1 (PD-1), cytotoxic T lymphocyte-associated molecule 4 (CTLA-4), T cell immunoglobulin (Ig) and mucin domain-containing protein 3 (TIM-3), B and T lymphocyte attenuator (BTLA), V-domain Ig suppressor of T cell activation (VISTA), T-cell Ig and ITIM domain (TIGIT), CD200, and lymphocyte activation gene 3 (LAG-3) belong to co-inhibitory molecules. If this balance was disrupted and the activation of T cells was increased, autoimmune diseases (AIDs) might be induced. Even in the treatment of malignant tumors, activation of T cells by immune checkpoint inhibitors (ICIs) may result in AIDs known as rheumatic immune-related adverse events (Rh-irAEs), suggesting the importance of ICs in AIDs. In this review, we summarized the features of AAV induced by immunotherapy using ICIs in patients with malignant tumors, and then reviewed the biological characteristics of different ICs. Our aim was to explore potential targets in ICs for future treatment of AAV.

Role of tumor necrosis factor receptor-associated factor 5 in B- and T-lymphocytes

Tumor necrosis factor receptor (TNFR)-associated factors (TRAFs) are a family of intracellular signaling adaptors that associate with the cytoplasmic tails of a diverse range of lymphocyte receptors, including members of the TNFR superfamily, the Toll-like receptor (TLR)/interleukin-1 (IL-1) receptor superfamily, and the IL-6 receptor family that are major targets for therapeutic intervention for inflammatory diseases. TRAF5 is one of the seven family members of the TRAF family and is highly expressed by B- and T-lymphocytes. As compared to other family members, the biological and pathophysiological functions of TRAF5 have remained ambiguous since its discovery. TRAF5 promotes lymphocyte signaling for the TNFR family molecules such as glucocorticoid-induced TNFR family-related protein (GITR), CD27, and CD40. In contrast, TRAF5 limits the activity of the common signaling receptor subunit glycoprotein 130 kDa (gp130) in CD4+ T cells that requires signaling by IL-6 and IL-27. TRAF5 also restrains TLR signaling in B cells. Thus, TRAF5 regulates lymphocyte signaling in both positive and negative ways. This review will summarize the findings of recent studies of TRAF5 in terms of how TRAF5 regulates signaling in lymphocytes and other cell types and how TRAF5 expression contributes to inflammatory and autoimmune diseases in mice and humans.

Quantitative systems pharmacology model of GITR-mediated T cell dynamics in tumor microenvironment.

T cell interaction in the tumor microenvironment is a key component of immuno-oncology therapy. Glucocorticoid-induced tumor necrosis factor receptor (TNFR)-related protein (GITR) is expressed on immune cells including regulatory T cells (Tregs) and effector T cells (Teffs). Preclinical data suggest that agonism of GITR in combination with Fc-γ receptor-mediated depletion of Tregs results in increased intratumoral Teff:Treg ratio and tumor shrinkage. A novel quantitative systems pharmacology (QSP) model was developed for the murine anti-GITR agonist antibody, DTA-1.mIgG2a, to describe the kinetics of intratumoral Tregs and Teffs in Colon26 and A20 syngeneic mouse tumor models. It adequately captured the time profiles of intratumoral Treg and Teff and serum DTA-1.mIgG2a and soluble GITR concentrations in both mouse models, and described the response differences between the two models. The QSP model provides a quantitative understanding of the trade-off between maximizing Treg depletion versus Teff agonism, and offers insights to optimize drug design and dose regimen.

196TiP A phase I study of REGN6569, a GITR monoclonal antibody (mAb), in combination with cemiplimab in patients with advanced solid tumour malignancies

REGN6569 is a fully human immunoglobulin G1 mAb that is highly specific for glucocorticoid-induced tumour necrosis factor receptor–related protein (GITR). GITR is expressed on several immune cell subtypes, notably regulatory T cells (Tregs). REGN6569 has demonstrated in vitro antibody-dependent cell-mediated cytotoxicity (ADCC) with greater cytotoxicity against GITR expressing Tregs than CD8+ T cells. GITR mAbs have shown preclinical antitumour efficacy. Anti-GITR and anti–programmed cell death-1 (PD-1) combination therapy has synergistic biological activity and may optimise immune checkpoint inhibitor (ICI) treatment in patients with advanced solid tumours.

GITRL impairs the immunosuppressive function of MDSCs via PTEN-mediated signaling pathway in experimental Sjögren syndrome.

Recent studies have revealed a role of the ligand for glucocorticoid-induced TNFR family-related protein (GITRL) in mediating functional dysregulations of myeloid-derived suppressor cells (MDSCs) in the pathogenesis of primary Sjögren syndrome (pSS), but the underlying molecular mechanism is largely unclear. In this study, we aimed to elucidate GITRL-mediated signaling pathways in MDSCs during the development of experimental SS (ESS). MDSCs were stimulated with recombinant GITRL, the activation of PTEN, AKT and STAT3 in MDSCs was analyzed by Western blot. MDSCs with different treatment were adoptively transferred to ESS mice. ELISA was used to detect the level of autoantibodies. Proportions of Th1 and Th17 cells were examined by flow cytometry. Histological evaluation of glandular destruction was analyzed by hematoxylin and eosin (HE) staining. The interaction of GITR, TRAF3 and PP2A was detected by CoIP. Upon the engagement of GITR on MDSCs, PTEN was activated and led to the inhibition of downstream AKT/STAT3 signaling pathway, therefore, resulting in the impaired immunosuppressive function of MDSCs. In ESS mice, blocking the activity of PTEN could efficiently restore the immunomodulatory effect of MDSCs and alleviate the progression of ESS. Furthermore, TRAF3 was found to bind to GITR, and then recruited PP2A to dephosphorylate PTEN, thus enhancing the activity of PTEN. This study elucidated the molecular mechanism underlying the effect of GITRL in regulating the function of MDSCs, which may provide a new therapeutic target for the treatment of pSS.

Selected Articles from This Issue

Previous treatment strategies for medulloblastoma have shown moderate improvement in response. However, the long-term overall survival remains disappointing, and many survivors have profound long-term complications. Therefore, there is a tremendous need to develop novel, improved, and safer therapeutic strategies for medulloblastoma. The critical tumor-stroma interactions mediated by the PlGF/NRP1 pathway make it an attractive target. Sholler and colleagues report a phase I, open-label, multicenter, dose-escalation study of the anti-PlGF antibody, TB-403, in pediatric subjects. TB-403 treatment was well tolerated and induced stable disease in high-risk, heavily pretreated relapsed medulloblastoma allowing for excellent quality of life. These findings indicate that treatment with TB-403 may represent a potentially transformative therapy for children with medulloblastoma and should be tested in larger studies.Costimulatory molecules expressed on the surface of T cells—such as 4-1BB, OX40, inducible T-cell costimulator (ICOS), and glucocorticoid-induced tumor necrosis factor receptor (GITR)—are potential targets to enhance T-cell antitumor activity. To evaluate the immunomodulatory effects of GITR agonist TRX518, Davar and colleagues designed a phase 1b study evaluating TRX518 alone and in combination with rational partners. While efficacy was modest, the authors consistently observed reductions in Tregs along with CD8+ T cell activation in responders. The pharmacodynamic effects of TRX518 upon Tregs suggests GITR agonism may require additional agents to effect greater Treg modulation and/or simultaneous targeting of alternative T-cell exhaustion pathways for clinical benefit.Desmoid fibromatosis (DF) is a rare disease affecting young adults. Spontaneous regression has been described in retrospective series. In this prospective observational study of 108 patients affected by primary sporadic DF primarily managed by active surveillance, Colombo and colleagues report the first prospective confirmation of spontaneous regression followed by regressions even after RECIST progression. They observed spontaneous regression in 56% of the patients (27/108 [25%] as an initial event plus 33/108 [31%] after initial progression). This supports active surveillance as the primary approach to the disease. Patients with larger tumors, extremity location and S45F beta-catenin mutations were at higher risk of receiving an active treatment and may deserve a more intense follow-up.Adjuvant immunotherapy produces durable benefit for patients with resected melanoma, but many develop recurrence and/or immune-related adverse events. In this study, Johannet and colleagues analyzed pre-treatment serum from 950 resected melanoma patients from two phase III randomized controlled trials of adjuvant immunotherapy: CheckMate 238 (ipilimumab vs nivolumab) and CheckMate 915 (nivolumab vs ipilimumab plus nivolumab). They identified autoantibody (autoAb) signatures for nivolumab, ipilimumab, and ipilimumab plus nivolumab that could be used to predict disease recurrence and severe immune-related adverse events. The composite panel of autoAb signatures can allow for the simultaneous risk stratification of patients according to their likelihood of recurring and suffering severe toxicity.

The Proportion of Vδ1T Cells in Peripheral Blood Correlated with Prognosis of Sepsis.

Sepsis is a serious condition with a high mortality rate, and septic patients often have organ dysfunction, low tissue perfusion and hypoxia, lactic acidosis, oliguria, or functional brain changes. To observe the number and the function of Vδ1T cells in peripheral blood of septic patients, to analyze the clinical significance of detecting Vδ1T cells, and to clarify the correlation of their presence with the prognosis of sepsis. The basic data of the septic patients were recorded at admission. The immunosuppressive function-related molecules on the surface of Vδ1T cells were detected, and the immunosuppressive function of Vδ1T cells was also evaluated. Compared with the healthy controls, the proportion of Vδ1T cells in the blood of septic patients significantly decreased (P<0.01). The proportion of Vδ1T cells in septic patients correlated with the patients' condition (P<0.05). The expression of glucocorticoid-induced tumor necrosis factor receptor (GITR), cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), and T-cell immunoglobulin and mucin domain-containing protein 3 (TIM-3) on the surface of Vδ1T cells in the blood of septic patients significantly increased (P<0.01). The increase of Vδ1T cells in septic patients had inhibitory effects on T cell proliferation and interferon (IFN)-γ secretion. These findings implied that the immunosuppression of Vδ1Tcells in the peripheral blood of septic patients was significantly higher than that of the healthy controls (P<0.01). Changes in Vδ1T cells in septic patients were closely related to the patient's condition and prognosis.

Combinations of anti-GITR antibody and CD28 superagonist induce permanent allograft acceptance by generating type 1 regulatory T cells.

Type 1 regulatory T (Tr1) cells represent a subset of IL-10–producing CD4+Foxp3− T cells and play key roles in promoting transplant tolerance. However, no effective pharmacological approaches have been able to induce Tr1 cells in vivo. We herein report the combined use of a CD28 superagonist (D665) and anti–glucocorticoid-induced tumor necrosis factor receptor–related protein monoclonal antibody (G3c) to induce Tr1 cells in vivo. Large amounts of IL-10/interferon-γ–co-producing CD4+Foxp3− Tr1 cells were generated by D665-G3c sequential treatment in mice. Mechanistic studies suggested that D665-G3c induced Tr1 cells via transcription factors Prdm1 and Maf. G3c contributed to Tr1 cell generation via the activation of mitogen-activated protein kinase–signal transducer and activator of transcription 3 signaling. Tr1 cells suppressed dendritic cell maturation and T cell responses and mediated permanent allograft acceptance in fully major histocompatibility complex–mismatched mice in an IL-10–dependent manner. In vivo Tr1 cell induction is a promising strategy for achieving transplant tolerance.

The Multi-Kinase Inhibitor Lucitanib Enhances the Antitumor Activity of Coinhibitory and Costimulatory Immune Pathway Modulators in Syngeneic Models.

Lucitanib is a multi-tyrosine kinase inhibitor whose targets are associated with angiogenesis and other key cancer and immune pathways. Its antiangiogenic properties are understood, but lucitanib's immunomodulatory activity is heretofore unknown. Lucitanib exhibited such activity in vivo, increasing CD3 + , CD8 + , and CD4 + T cells and decreasing dendritic cells and monocyte-derived suppressor cells in mouse spleens. Depletion of CD8 + T cells from syngeneic MC38 colon tumor-bearing mice reduced the antitumor efficacy of lucitanib and revealed a CD8 + T-cell-dependent component of lucitanib's activity. The combination of lucitanib and costimulatory immune pathway agonists targeting 4-1BB, glucocorticoid-induced TNFR (GITR), inducible T-cell co-stimulator (ICOS), or OX40 exhibited enhanced antitumor activity compared with each single agent in immunocompetent tumor models. Lucitanib combined with blockade of cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) or programmed cell death protein-1 (PD-1) coinhibitory immune pathways also showed enhanced antitumor activity over the single agents in multiple models. In CT26 tumors, lucitanib, alone or combined with anti-PD-1, reduced CD31 + vessels and depleted F4/80 + macrophages. Combination treatment also increased the number of intratumoral T cells. Gene expression in pathways associated with immune activity was upregulated by lucitanib in MC38 tumors and further potentiated by combination with anti-PD-1. Accordingly, lucitanib, alone or combined with anti-PD-1, increased intratumoral CD8 + T-cell abundance. Lucitanib's antitumor and pharmacodynamic activity, alone or combined with anti-PD-1, was not recapitulated by specific vascular endothelial growth factor receptor-2 (VEGFR2) inhibition. These data indicate that lucitanib can modulate vascular and immune components of the tumor microenvironment and cooperate with immunotherapy to enhance antitumor efficacy. They support the clinical development of lucitanib combined with immune pathway modulators to treat cancer.

Plasma Phage Load is Positively Related to the Immune Checkpoints in Patients Living with Human Immunodeficiency Virus.

Microbial Translocation (MT) and altered gut microbiota are involved in immune activation and inflammation, whereas immune checkpoint proteins play an important role in maintaining immune self-tolerance and preventing excessive immune activation. This study aims to investigate the relationship between plasma phage load and immune homeostasis in people living with HIV(PLWH). We recruited 15 antiretroviral therapy (ART)-naive patients, 23 ART-treated (AT) patients, and 34 Healthy Participants (HP) to explore the relationship between the plasma phage load and immune checkpoint proteins. The Deoxyribonucleic Acid (DNA) load of the lambda (λ) phage was detected using fluorescence quantitative Polymerase Chain Reaction (PCR). The Immune Checkpoints (ICPs) were detected using multiplex immunoassay. Our study demonstrated that the plasma phage load was increased in people living with HIV (PLWH) (P<0.05), but not in the ART-naive and AT groups (P>0.05). Plasma ICPs, including cluster of differentiation 27 (CD27), soluble glucocorticoid-induced Tumor Necrosis Factor (TNF) receptor (sGITR), soluble cluster of differentiation 80 (sCD80), sCD86, soluble glucocorticoidinduced TNF receptor-related ligand (sGITRL), soluble induced T-cell Costimulatory (sICOS), sCD40, soluble toll-like receptor 2 (sTLR2), and sCD28, were markedly decreased among the ARTnaive group (P<0.05) but not in the AT and HP groups (P>0.05). The plasma phage load was positively correlated with ICP and C-reactive protein (CRP) levels in PLWH (P<0.05). Our study indicated that the plasma phage load in PLWH was positively related to the expression of ICPs and inflammation, which may be used as a promising marker for the immune level of PLWH.

Combination with Toll-like receptor 4 (TLR4) agonist reverses GITR agonism mediated M2 polarization of macrophage in Hepatocellular carcinoma

ABSTRACT The glucocorticoid-induced tumor necrosis factor receptor (GITR) agonistic antibody (DTA-1) has been proved to elicit robust immune response in various kinds of tumors. However, only a few of the HCC patients could benefit from it, and the mechanism of DTA-1 resistance remains unknown. Here, we measured GITR expression in different immunocytes in HCC microenvironment, and we observed that tumor-infiltrating regulatory T cells (Ti-Tregs) significantly expressed GITR, which were associated with poor prognosis. Meanwhile, we analyzed the variation of tumor-infiltrating immune components and associated inflammation response after DTA-1 treatment in orthotopic liver cancer model of mice. Surprisingly, DTA-1 treatment reduced the infiltration of Tregs but failed to activate CD8+ T cells and elicit antitumor efficacy. In particular, DTA-1 treatment enforced alternative M2 polarization of macrophage, and macrophage depletion could enhance DTA-1-mediated antitumor efficacy in HCC. Mechanistically, macrophage M2 polarization attributed to the IL-4 elevation induced by Th2 immune activation in the treatment of DTA-1, resulting in DTA-1 resistance. Furthermore, Toll-like receptor 4 (TLR4) agonist could diminish the macrophage (M2) polarization and reverse the M2-mediated DTA-1 resistance, eliciting robust antitumor effect in HCC. Our finding demonstrated that the TLR4 agonist synergized with DTA-1 was a potential strategy for HCC treatment.

Neoadjuvant Chemoradiotherapy Changes the Landscape of Soluble Immune Checkpoint Molecules in Patients With Locally Advanced Rectal Cancer.

BackgroundWe aimed to investigate clinical implications of specific soluble immune checkpoint molecules (sICMs) in locally advanced rectal cancer (LARC) patients treated with neoadjuvant chemoradiotherapy (nCRT).MethodsWe prospectively enrolled 30 LARC patients treated with nCRT and collected blood samples from them before, during, and after nCRT for prospective studies. Immune checkpoints often refer to T cell surface molecules influencing the immune response. Immune checkpoints, in the form of a soluble monomeric form, is widely present in blood. In the study, eight immune checkpoint-related plasma proteins, including programmed death-ligand 1 (PD-L1), CD80, CD86, CD28, CD27, glucocorticoid-induced tumor necrosis factor receptor (GITR), GITR ligand (GITRL), and inducible T-cell costimulator (ICOS), were measured using the Luminex platform. Two independent pathologists categorized patients as the good responders and the poor responders according to Dworak tumor regression grade (TRG).ResultsOf the 30 patients, the levels of sPD-L1, sCD80, sCD86, sCD28, sGITR, sGITRL, sCD27, and sICOS decreased during nCRT (Pre-nCRT vs. During-nCRT, all p<0.05) but were restored after nCRT treatment (Pre-nCRT vs. Post-nCRT, all p>0.05). In the 14 good responders, the levels of sICMs, other than sGITR (p=0.081) and sGITRL (p=0.071), decreased significantly during nCRT (Pre-nCRT vs. During-nCRT, p<0.05), but they were all significantly increased after nCRT (During-nCRT vs. Post-nCRT, all p<0.05). In the 16 poor responders, only sCD80 was significantly reduced during nCRT (Pre-nCRT vs. During-nCRT, p<0.05), and none was significantly increased after nCRT (During-nCRT vs. Post-nCRT, all p<0.05). High levels of sICMs before nCRT were associated with poor response (all OR≥1). The Pre-model that incorporated the 8 sICMs before nCRT yielded a good predictive value (AUC, 0.848) and was identified as an independent predictor of treatment response (OR, 2.62; 95% CI, 1.11-6.18; p=0.027).ConclusionOur results suggest chemoradiotherapy could influence the change of sPD-L1, sCD80, sCD86, sCD28, sGITR, sGITRL, sCD27, and sICOS in patients with LARC. The levels of the majority of soluble immune checkpoint molecules were reduced during nCRT and then restored at the end of nCRT, particularly in patients who responded well to nCRT. Combined baseline sICMs can be developed to predict treatment response.

Concurrent Chemoradiotherapy Increases the Levels of Soluble Immune Checkpoint Proteins in Patients with Locally Advanced Cervical Cancer.

Purpose Concurrent chemoradiotherapy (CCRT) has been widely applied to locally advanced cervical cancer (LACC) patients, inducing the massive release of antigen and systematic immunomodulatory effects. However, its effect on the soluble immune checkpoint proteins (sICPs) remains unclear, which might play a key role in the immune response. Therefore, the current study explored changes in the levels of 16 sICPs in LACC patients during CCRT. Methods We prospectively enrolled fifty-one LACC patients treated with CCRT and collected patients' blood before, during and after CCRT. The levels of 16 sICPs were measured using the Luminex platform, and the changes were measured using Friedman test with Bonferroni's posttest. One month after CCRT, the tumor response was evaluated according to the RECIST 1.1 guidelines. Results The levels of soluble T-cell immunoglobulin and mucin-domain containing-3 (sTIM-3) significantly increased during CCRT (P = 0.041), while those of the soluble B and T lymphocyte attenuator (sBTLA), sCD40, soluble glucocorticoid-induced tumor necrosis factor receptor ligand (sGITRL), sCD80, sCD86, sPD-1, sPD-L1, sCTLA-4, and soluble inducible T-cell costimulator (sICOS) significantly increased after CCRT (all P < 0.05). Other sICPs showed no significant changes throughout the CCRT (all P > 0.05). 41 (80%), 8 (16%), and 2 (4%) patients showed complete response (CR), partial response (PR), and stable disease (SD) after CCRT, respectively. Interestingly, the level of soluble lymphocyte-activation gene 3 (sLAG-3) was significantly higher among the PR/SD patients as compared to the CR after CCRT (P = 0.009). Conclusions This study revealed that CCRT might elevate the serum levels of sTIM-3, sBTLA, sCD40, sGITRL, sCD80, sCD86, sPD-1, sPD-L1, sCTLA-4, and sICOS in the patients with LACC. The sLAG-3 level was higher in the patients with poor response to CCRT. These findings revealed the dynamic changes in the sICPs levels during CCRT, which might be helpful in designing optimal treatment strategies for LACC patients.

GITR/GITRL reverse signalling modulates the proliferation of hepatic progenitor cells by recruiting ANXA2 to phosphorylate ERK1/2 and Akt

Hepatic stem/progenitor cells are the major cell compartment for tissue repair when hepatocyte proliferation is compromised in chronic liver diseases, but the expansion of these cells increases the risk of carcinogenesis. Therefore, it is essential to explore the pathways restricting their expansion and abnormal transformation. The ligand of glucocorticoid-induced tumour necrosis factor receptor (GITRL) showed the most highly increased expression in hepatic progenitor cells treated with transforming growth factor (TGF)-β1. If overexpressed by hepatic progenitor cells, GITRL stimulated cell proliferation by activating the epithelial–mesenchymal transition pathway and enhancing ERK1/2 and Akt phosphorylation via GITRL binding to ANXA2. However, GITR, the specific GITRL receptor, suppressed the epithelial–mesenchymal transition pathway of GITRL-expressing cells and decreased their growth by dissociating ANXA2 from GITRL and reducing downstream ERK1/2 and Akt phosphorylation. This study identifies GITR/GITRL reverse signalling as a cross-interaction pathway between immune cells and hepatic stem/progenitor cells that restricts the expansion of hepatic stem/progenitor cells and reduces the possibility of carcinogenesis.