Cytokine-armed dendritic cell progenitors for antigen-agnostic cancer immunotherapy.

Dendritic cells (DCs) are antigen-presenting myeloid cells that regulate T cell activation, trafficking and function. Monocyte-derived DCs pulsed with tumor antigens have been tested extensively for therapeutic vaccination in cancer, with mixed clinical results. Here, we present a cell-therapy platform based on mouse or human DC progenitors (DCPs) engineered to produce two immunostimulatory cytokines, IL-12 and FLT3L. Cytokine-armed DCPs differentiated into conventional type-I DCs (cDC1) and suppressed tumor growth, including melanoma and autochthonous liver models, without the need for antigen loading or myeloablative host conditioning. Tumor response involved synergy between IL-12 and FLT3L and was associated with natural killer and T cell infiltration and activation, M1-like macrophage programming and ischemic tumor necrosis. Antitumor immunity was dependent on endogenous cDC1 expansion and interferon-γ signaling but did not require CD8+ T cell cytotoxicity. Cytokine-armed DCPs synergized effectively with anti-GD2 chimeric-antigen receptor (CAR) T cells in eradicating intracranial gliomas in mice, illustrating their potential in combination therapies.

Iguratimod attenuated fibrosis in systemic sclerosis via targeting early growth response 1 expression.

BACKGROUND: The early growth response 1 (EGR1) is a central transcription factor involved in systemic sclerosis (SSc) pathogenesis. Iguratimod is a synthesized anti-rheumatic disease-modifying drug, which shows drastic inhibition to EGR1 expression in B cells. This study is aiming to investigate the anti-fibrotic effect of iguratimod in SSc. METHODS: EGR1 was detected by immunofluorescence staining real-time PCR or western blot. Iguratimod was applied in EGR1 overexpressed or knockdown human dermal fibroblast, bleomycin pre-treated mice, tight skin 1 mice, and SSc skin xenografts. RNA sequencing was performed in cultured fibroblast and xenografts to identify the iguratimod regulated genes. RESULTS: EGR1 overexpressed predominantly in non-immune cells of SSc patients. Iguratimod reduced EGR1 expression in fibroblasts and neutralized changes of EGR1 response genes regulated by TGFß. The extracellular matrix (ECM) production and activation of fibroblasts were attenuated by iguratimod while EGR1 overexpression reversed this effect of iguratimod. Iguratimod ameliorated the skin fibrosis induced by bleomycin and hypodermal fibrosis in TSK-1 mice. Decreasing in the collagen content as well as the density of EGR1 or TGFß positive fibroblasts of skin xenografts from naïve SSc patients was observed after local treatment of iguratimod. CONCLUSION: Targeting EGR1 expression is a probable underlying mechanism for the anti-fibrotic effect of iguratimod.

Intestinal B cells license metabolic T-cell activation in NASH microbiota/antigen-independently and contribute to fibrosis by IgA-FcR signalling.

BACKGROUND & AIMS: The progression of non-alcoholic steatohepatitis (NASH) to fibrosis and hepatocellular carcinoma (HCC) is aggravated by auto-aggressive T cells. The gut-liver axis contributes to NASH, but the mechanisms involved and the consequences for NASH-induced fibrosis and liver cancer remain unknown. We investigated the role of gastrointestinal B cells in the development of NASH, fibrosis and NASH-induced HCC. METHODS: C57BL/6J wild-type (WT), B cell-deficient and different immunoglobulin-deficient or transgenic mice were fed distinct NASH-inducing diets or standard chow for 6 or 12 months, whereafter NASH, fibrosis, and NASH-induced HCC were assessed and analysed. Specific pathogen-free/germ-free WT and µMT mice (containing B cells only in the gastrointestinal tract) were fed a choline-deficient high-fat diet, and treated with an anti-CD20 antibody, whereafter NASH and fibrosis were assessed. Tissue biopsy samples from patients with simple steatosis, NASH and cirrhosis were analysed to correlate the secretion of immunoglobulins to clinicopathological features. Flow cytometry, immunohistochemistry and single-cell RNA-sequencing analysis were performed in liver and gastrointestinal tissue to characterise immune cells in mice and humans. RESULTS: Activated intestinal B cells were increased in mouse and human NASH samples and licensed metabolic T-cell activation to induce NASH independently of antigen specificity and gut microbiota. Genetic or therapeutic depletion of systemic or gastrointestinal B cells prevented or reverted NASH and liver fibrosis. IgA secretion was necessary for fibrosis induction by activating CD11b+CCR2+F4/80+CD11c-FCGR1+ hepatic myeloid cells through an IgA-FcR signalling axis. Similarly, patients with NASH had increased numbers of activated intestinal B cells; additionally, we observed a positive correlation between IgA levels and activated FcRg+ hepatic myeloid cells, as well the extent of liver fibrosis. CONCLUSIONS: Intestinal B cells and the IgA-FcR signalling axis represent potential therapeutic targets for the treatment of NASH. IMPACT AND IMPLICATIONS: There is currently no effective treatment for non-alcoholic steatohepatitis (NASH), which is associated with a substantial healthcare burden and is a growing risk factor for hepatocellular carcinoma (HCC). We have previously shown that NASH is an auto-aggressive condition aggravated, amongst others, by T cells. Therefore, we hypothesized that B cells might have a role in disease induction and progression. Our present work highlights that B cells have a dual role in NASH pathogenesis, being implicated in the activation of auto-aggressive T cells and the development of fibrosis via activation of monocyte-derived macrophages by secreted immunoglobulins (e.g., IgA). Furthermore, we show that the absence of B cells prevented HCC development. B cell-intrinsic signalling pathways, secreted immunoglobulins, and interactions of B cells with other immune cells are potential targets for combinatorial NASH therapies against inflammation and fibrosis.

Hypoxia-inducible factor-1α regulates the interleukin-6 production by B cells in rheumatoid arthritis.

Objectives: Rheumatoid arthritis (RA) is a disease characterised by bone destruction and systemic inflammation, and interleukin-6 (IL-6) is a therapeutic target for treating it. The study aimed at investigating the sources of IL-6 and the influence of hypoxia-inducible factor-1α (HIF-1α) on IL-6 production by B cells in RA patients. Methods: The phenotype of IL-6-producing cells in the peripheral blood of RA patients was analysed using flow cytometry. Bioinformatics, real-time polymerase chain reaction, Western blot and immunofluorescence staining were used to determine the IL-6 production and HIF-1α levels in B cells. A dual-luciferase reporter assay and chromatin immunoprecipitation were used to investigate the regulatory role of HIF-1α on IL-6 production in human and mouse B cells. Results: Our findings revealed that B cells are major sources of IL-6 in the peripheral blood of RA patients, with the proportion of IL-6-producing B cells significantly correlated with RA disease activity. The CD27-IgD+ naïve B cell subset was identified as the typical IL-6-producing subset in RA patients. Both HIF-1α and IL-6 were co-expressed by B cells in the peripheral blood and synovium of RA patients, and HIF-1α was found to directly bind to the IL6 promoter and enhance its transcription. Conclusion: This study highlights the role of B cells in producing IL-6 and the regulation of this production by HIF-1α in patients with RA. Targeting HIF-1α might provide a new therapeutic strategy for treating RA.

HRCT quantitative analysis of airway remodeling and airway trapping in the small airway asthma phenotype and its correlation with pulmonary function.

OBJECTIVES: We aimed to explore whether large airway remodeling and small airway structural changes exist in subjects with small airway asthma phenotype and to evaluate the relationships between quantitative high-resolution computed tomography (qHRCT) parameters and lung function. METHODS: We enrolled 15 subjects with small airway asthma phenotype and 18 healthy controls. The two groups were matched by age, sex and body square area (BSA) with propensity score matching (PSM). Pulmonary function and qHRCT parameters [wall thickness (WT), wall area (WA), lumen area (LA), wall area percentage (WA%) of the 4th-6th generations in the right upper lobe apical segmental bronchus (RB1), adjusted by BSA, WT/BSA, WA/BSA, and LA/BSA, relative volume change -860 HU to -950 HU (RVC-860 to -950) and the expiration to inspiration ratio of mean lung density (MLDE/I)) were compared between the groups. Correlation analysis was employed to assess the relationship between qHRCT parameters and pulmonary function. RESULTS: The small airway asthma phenotype had significantly higher WA%, RVC-860 to -950 and MLDE/I and lower LA/BSA than the healthy control. Additionally, we found moderate to strong correlations between impulse oscillation (IOS) indices and WA6% and WT6/BSA. No significant correlation was found between bronchial parameters and air trapping parameters (p > 0.05). CONCLUSIONS: Combining physiological tests with imaging approaches can lead to better evaluation of small airway disfunction (SAD) in asthmatic patients. Additionally, despite nonexistent airflow obstruction in patients with small airway asthma phenotype, large airway remodeling and small airway structural changes may appear simultaneously in the early stage of disease.

RIPK1 downregulation enhances neutrophil extracellular traps in psoriasis.

Introduction: Psoriasis is an immune-mediated systemic disease. Neutrophils are enriched in psoriasis lesions and can form neutrophil extracellular traps (NETs) to activate keratinocytes. Receptor-interacting protein kinase RIPK1 and RIPK3 are involved in necroptosis and NET formation. Aim: To elucidate whether RIPK1 regulates circulating neutrophils to form NETs and inflammation in psoriasis. Material and methods: Blood samples of psoriasis patients (n = 20) and healthy controls (n = 20) were detected by flow cytometry. The expression level of RIPK1/3 in isolated circulating neutrophils from psoriasis patients (n = 17) and healthy controls (n = 17) was examined by quantitative real-time PCR. SYTOX Green dye and PicoGreen reagent were used to detect NET formation and DNA release in neutrophils under the stimulation of phorbol 12-myristate 13-acetate (PMA) and necrostain-1 (Nec-1). Correlation analysis was performed between RIPK1/3 expression and Psoriasis Area Severity Index (PASI), neutrophil-to-lymphocyte ratio (NLR). Results: RIPK1 and RIPK3 expression in protein levels were decreased in monocytes and neutrophils from peripheral blood of psoriasis patients. In isolated psoriasis neutrophils, RIPK1 and Caspase8 mRNA were downregulated while RIPK3 and MLKL mRNA were elevated, leading to the necroptosis pathway. In addition, RIPK1-inhitor-necrostatin-1 (Nec-1) enhanced NETosis in psoriasis neutrophils in vitro. More importantly, there is a negative correlation between RIPK1 and psoriasis disease severity. Conclusions: Our data demonstrated that downregulated RIPK1 expression in psoriasis neutrophils may enhance NET generation. RIPK1 may be identified as a novel therapeutic target in psoriasis.

CXCR2 inhibition enables NASH-HCC immunotherapy.

OBJECTIVE: Hepatocellular carcinoma (HCC) is increasingly associated with non-alcoholic steatohepatitis (NASH). HCC immunotherapy offers great promise; however, recent data suggests NASH-HCC may be less sensitive to conventional immune checkpoint inhibition (ICI). We hypothesised that targeting neutrophils using a CXCR2 small molecule inhibitor may sensitise NASH-HCC to ICI therapy. DESIGN: Neutrophil infiltration was characterised in human HCC and mouse models of HCC. Late-stage intervention with anti-PD1 and/or a CXCR2 inhibitor was performed in murine models of NASH-HCC. The tumour immune microenvironment was characterised by imaging mass cytometry, RNA-seq and flow cytometry. RESULTS: Neutrophils expressing CXCR2, a receptor crucial to neutrophil recruitment in acute-injury, are highly represented in human NASH-HCC. In models of NASH-HCC lacking response to ICI, the combination of a CXCR2 antagonist with anti-PD1 suppressed tumour burden and extended survival. Combination therapy increased intratumoural XCR1+ dendritic cell activation and CD8+ T cell numbers which are associated with anti-tumoural immunity, this was confirmed by loss of therapeutic effect on genetic impairment of myeloid cell recruitment, neutralisation of the XCR1-ligand XCL1 or depletion of CD8+ T cells. Therapeutic benefit was accompanied by an unexpected increase in tumour-associated neutrophils (TANs) which switched from a protumour to anti-tumour progenitor-like neutrophil phenotype. Reprogrammed TANs were found in direct contact with CD8+ T cells in clusters that were enriched for the cytotoxic anti-tumoural protease granzyme B. Neutrophil reprogramming was not observed in the circulation indicative of the combination therapy selectively influencing TANs. CONCLUSION: CXCR2-inhibition induces reprogramming of the tumour immune microenvironment that promotes ICI in NASH-HCC.

The Value of Impulse Oscillometric Parameters and Quantitative HRCT Parameters in Differentiating Asthma-COPD Overlap from COPD.

PURPOSE: To evaluate the value of impulse oscillometry (IOS) and quantitative HRCT parameters for differentiating asthma-COPD overlap (ACO) in COPD patients. PATIENTS AND METHODS: We enrolled 44 controls and 66 COPD patients, divided into the pure COPD group (n=40) and the ACO group (n=26). Spearman correlation analysis was utilized to assess the relationship between the quantitative HRCT and IOS parameters. A binary logistic regression analysis was performed to analyze the associations between the different variables and the risk of ACO. Receiver operating characteristic (ROC) curves were employed to identify the optimal cutoff and assess the diagnostic value of relative volume change -856 HU to -950 HU (RVC-856 to -950), decrease in the resistance from 5 Hz to 20 Hz (R5-R20) and their combination in predicting ACO. Bootstrapping validation was used to evaluate the internal validation. The concordance index (C-index) and calibration plot were calculated to assess the discrimination and calibration of the prediction model. RESULTS: Binary logistic regression analysis indicated that RVC-856 to -950 and the IOS parameters (R5-R20, R5, X5) were independently correlated with a higher risk of developing ACO after adjusting for age, sex, body mass index (BMI), history of smoking, exacerbation and atopy or allergic rhinitis. A correlation analysis showed a good correlation between the pulmonary function parameters and RVC-856 to -950, with a weaker correlation with the % area of low attenuation (LAA%) in ACO patients. Combining RVC-856 to -950 and R5-R20 to predict ACO, the AUC was 0.909, and the optimal cutoff value was >-0.62 for RVC-856 to -950 and >0.09 for R5-R20. Good calibration and favorable discrimination were displayed with a higher C-index. CONCLUSION: More serious small airway impairment exists in ACO patients. The combination of RVC-856 to -950 and R5-R20 could be applied to differentiate ACO from COPD patients.

Metabolism-Associated Epigenetic and Immunoepigenetic Reprogramming in Liver Cancer.

Metabolic reprogramming and epigenetic changes have been characterized as hallmarks of liver cancer. Independently of etiology, oncogenic pathways as well as the availability of different energetic substrates critically influence cellular metabolism, and the resulting perturbations often cause aberrant epigenetic alterations, not only in cancer cells but also in the hepatic tumor microenvironment. Metabolic intermediates serve as crucial substrates for various epigenetic modulations, from post-translational modification of histones to DNA methylation. In turn, epigenetic changes can alter the expression of metabolic genes supporting on the one hand, the increased energetic demand of cancer cells and, on the other hand, influence the activity of tumor-associated immune cell populations. In this review, we will illustrate the most recent findings about metabolic reprogramming in liver cancer. We will focus on the metabolic changes characterizing the tumor microenvironment and on how these alterations impact on epigenetic mechanisms involved in the malignant progression. Furthermore, we will report our current knowledge about the influence of cancer-specific metabolites on epigenetic reprogramming of immune cells and we will highlight how this favors a tumor-permissive immune environment. Finally, we will review the current strategies to target metabolic and epigenetic pathways and their therapeutic potential in liver cancer, alone or in combinatorial approaches.

SARS-CoV-2 in severe COVID-19 induces a TGF-ß-dominated chronic immune response that does not target itself.

The pathogenesis of severe COVID-19 reflects an inefficient immune reaction to SARS-CoV-2. Here we analyze, at the single cell level, plasmablasts egressed into the blood to study the dynamics of adaptive immune response in COVID-19 patients requiring intensive care. Before seroconversion in response to SARS-CoV-2 spike protein, peripheral plasmablasts display a type 1 interferon-induced gene expression signature; however, following seroconversion, plasmablasts lose this signature, express instead gene signatures induced by IL-21 and TGF-ß, and produce mostly IgG1 and IgA1. In the sustained immune reaction from COVID-19 patients, plasmablasts shift to the expression of IgA2, thereby reflecting an instruction by TGF-ß. Despite their continued presence in the blood, plasmablasts are not found in the lungs of deceased COVID-19 patients, nor does patient IgA2 binds to the dominant antigens of SARS-CoV-2. Our results thus suggest that, in severe COVID-19, SARS-CoV-2 triggers a chronic immune reaction that is instructed by TGF-ß, and is distracted from itself.

Corrigendum: Signal Transducer and Activator of Transcription 3 Hyperactivation Associates With Follicular Helper T Cell Differentiation and Disease Activity in Rheumatoid Arthritis.

[This corrects the article DOI: 10.3389/fimmu.2018.01226.].

Signal Transducer and Activator of Transcription 3 Hyperactivation Associates With Follicular Helper T Cell Differentiation and Disease Activity in Rheumatoid Arthritis.

Follicular helper T (Tfh) cells are the specialized CD4+ T cell subset that supports B cells to produce high-affinity antibodies and generate humoral memory. Not only is the function of Tfh cells instrumental to mount protect antibodies but also to support autoantibody production and promote systemic inflammation in autoimmune diseases. However, it remains unclear how the activation of Tfh cells is driven in autoimmune diseases. Here, we report that in patients with rheumatoid arthritis (RA), excessive generation of CXCR5+PD-1+ memory Tfh cells was observed and the frequency of memory Tfh cells correlated with disease activity score calculator for RA (DAS28). The differentiation of Tfh cells is dependent on signal transducer and activator of transcription 3 (STAT3), the key transcription factor downstream of cytokine signal pathways. A drastic increase of phosphorylated STAT3 (pSTAT3) in CD4+ T cells were detected in RA patients who also produced larger amounts of STAT3-stimulating cytokines, including IL-6, IL-21, IL-10, and leptin than those of healthy controls. Importantly, the phosphorylation status of STAT3 in CD4+ T cells positively correlated with the plasma concentration of IL-6 and the frequency of memory Tfh cells. This study reveals an IL-6-pSTAT3-Tfh immunoregulatory axis in the pathogenesis of RA and reinforces its candidature as biomarkers and targets for diagnosis and therapy.

[Expression and its promoter methylation of chemokine CXC ligand 14 in peripheral blood mononuclear cells from patients with lupus].

OBJECTIVE: To analyze the expression and its promoter methylation of chemokine CXC ligand 14 (CXCL14) in peripheral blood mononuclear cells (PBMCs) from patients with systemic lupus erythematosus (SLE). METHODS: The RNAs of PBMCs from 28 SLE patients and 20 healthy controls were isolated and reversely transcribed into cDNAs. Using GAPDH as the internal reference, the levels of CXCL14 ex-pression were detected by real-time polymerase chain reaction (PCR). The correlation between CXCL14 expression and the clinic pathological fe atures of SLE were further analyzed. DNA methylation was analyzed by bisulfite sequencing PCR (BSP). RESULTS: Our data indicated that the level of CXCL14 in the PBMC of SLE patients was statistically lower than that in healthy controls (P < 0.05). Further analysis showed that CXCL14 expression was negatively correlated with anti-Sj gren syndrome B antibody(anti-SSB antibody, P < 0.01) and albuminuria(P < 0.05). However, CXCL14 expression was not significantly correlated with the indexes of SLE activity, renal damage, the level of anti-ds-DNA antibodies, complement C3 and C-reactive protein. In addition, we further demonstrated that the CXCL14 promoter hypermethylation expres-sion was significant higher than healthy controls. CONCLUSIONS: Down-regulated of CXCL14 expression in PBMC maybe involved in the occur-rence or development of SLE disease. The loss of CXCL14 expression was regulated by promoter hypermethylation.