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Neutrophils might play an important role in the pathogenesis of autoimmune diseases, including type 1 diabetes (T1D), by contributing to immune dysregulation via a highly inflammatory program called neutrophil extracellular trap (NET) formation or NETosis, involving the extrusion of chromatin entangled with anti-microbial proteins. However, numerous studies reported contradictory data on NET formation in T1D. This might in part be due to the inherent heterogeneity of the disease and the influence of the disease developmental stage on neutrophil behavior. Moreover, there is a lack of a standardized method to measure NETosis in an unbiased and robust manner. In this study, we employed the Incucyte® ZOOM live-cell imaging platform to study NETosis levels in various subtypes of adult and pediatric T1D donors compared to healthy controls (HC) at baseline and in response to phorbol–myristate acetate (PMA) and ionomycin. Firstly, we determined that the technique allows for an operator-independent and automated quantification of NET formation across multiple time points, which showed that PMA and ionomycin induced NETosis with distinct kinetic characteristics, confirmed by high-resolution microscopy. NETosis levels also showed a clear dose-response curve to increasing concentrations of both stimuli. Overall, using Incucyte® ZOOM, no aberrant NET formation was observed over time in the different subtypes of T1D populations, irrespective of age, compared to HC. These data were corroborated by the levels of peripheral NET markers in all study participants. The current study showed that live-cell imaging allows for a robust and unbiased analysis and quantification of NET formation in real-time. Peripheral neutrophil measures should be complemented with dynamic quantification of NETing neutrophils to make robust conclusions on NET formation in health and disease.

The ideal composition of the perfusate for normothermic kidney perfusion is unknown, though the perfusate commonly used to perfuse human kidneys contains leukocyte-depleted packed red blood cells (RBC), as this is believed to prevent excessive inflammation. We performed a systematic search identifying 19 articles reporting on cytokine levels during normothermic pig or human kidney perfusion. Cytokine levels varied widely across the reported studies. No direct comparisons of perfusate cytokines during perfusion with RBC or whole blood were performed, and no data on how these levels are influenced by ischemia are available. Therefore, we compared perfusate IL-6, IL-1β, TNF-α, TGF-β, IL-10, IL-8, and CCL2 levels during 4 h normothermic pig kidney perfusion with a whole blood- or RBC-based perfusate. Kidneys were exposed to either 1 h of warm or 22 h of cold ischemia. We found no evidence of different perfusate cytokine or gene expression levels in whole blood or RBC perfusions. There was no clear evidence to suggest that cytokine concentrations differ between ischemically injured kidneys and controls. In conclusion, pro-inflammatory and anti-inflammatory cytokines and chemokines are detectable in the perfusate and urine of kidneys undergoing normothermic perfusion. It is unclear how cytokine levels change in different ischemic conditions and whether the use of a leukocyte filter plays a role. ispartof: Journal Of Clinical Medicine vol:11 issue:22 pages:1-11 ispartof: location:Switzerland status: Published online

Purpose: Patients with prior bariatric surgery (BS) are at risk to develop alcohol use disorder (AUD) and alcohol-related liver disease (ALD). Severe alcoholic hepatitis (sAH) is one of the most severe manifestations of ALD with a 28-day mortality of 20-50%. The impact of prior BS on patients presenting with sAH was assessed. Methods: From 01/2008 to 04/2021, consecutive patients admitted to a tertiary referral center with biopsy-proven sAH were included in a database. Results: One hundred fifty-eight sAH patients of which 28 patients had a history of BS (BS group) were identified. Of this BS group, 24 patients underwent a Roux-en-Y gastric bypass (RYGB), 3 a biliopancreatic diversion, 1 an adjustable gastric band, and no patients a sleeve gastrectomy. The proportion of patients with BS increased threefold over time during the study period. Patients in the BS group were significantly younger at diagnosis of sAH (44.3 years vs 52.4 years), were more frequently female, and had a higher body mass index and a higher grade of steatosis on liver biopsy. The correlation between BS and a younger age at diagnosis remained significant in a multivariate regression analysis. There were no differences in disease severity between both groups. Furthermore, there were no differences in corticosteroid response, 28-day, 90-day, or 1-year survival. Conclusion: Prior BS is independently associated with a younger age of presentation with sAH, but is not independently associated with a different disease severity or outcome. These findings support the need for early detection of AUD in patients who underwent BS, in particular RYGB.

A decrease or normalization of alkaline phosphatase (ALP) and bilirubin levels in patients treated for primary biliary cholangitis (PBC) predicts a better survival. Obeticholic acid (OCA) is the approved second-line therapy if ursodeoxycholic acid (UCDA) fails, but its use may worsen pruritus. Adding bezafibrate to UCDA improved biochemical markers of cholestatic liver injury and decreased pruritus severity. Because normalization of ALP and bilirubin was only achieved in a minority of patients in these studies, we explored whether bezafibrate (off-label drug) could improve the effect of OCA (licensed drug) on cholestasis. ispartof: HEPATOLOGY vol:73 issue:6 pages:2598-2600 ispartof: location:United States status: published

Background Neuregulin 4 (Nrg4), a novel adipokine enriched in brown adipose tissue has been observed to negatively regulate de novo hepatic lipogenesis and limit nonalcoholic fatty liver disease (NAFLD) progression to nonalcoholic steatohepatitis (NASH) in rodents. However, the role of Nrg4 in human NAFLD remains unclear to date. We analysed Nrg4 plasma levels and its association with liver disease severity together with the transcriptional profile of the Nrg4 pathway in liver and visceral adipose tissue (VAT) of NAFLD patients. Methods Plasma Nrg4 levels were measured in 65 NAFLD patients and 43 healthy controls (HC). Hepatic steatosis and fibrosis were diagnosed and quantified with chemical shift MRI and transient elastography respectively. Furthermore, blood lipid levels, HOMA-IR and systemic pro-inflammatory cytokines (TNF-α, IL-6 and IFN-γ) were analysed. Microarray analyses to assess differences in the Nrg4 and its receptor family ErbB pathway in liver and VAT from an independent patient group with biopsy proven NAFL (simple steatosis) (n = 4), NASH (n = 5) and normal liver (n = 6) were performed. Results Plasma Nrg4 levels were not significantly different between NAFLD patients and HC (p = 0.622). Furthermore, plasma Nrg4 levels did not correlate with the hepatic fat fraction (r = -0.028, p = 0.829) and were not significantly different between NAFLD patients with or without hepatic fibrosis (p = 0.087). Finally, the expression profile of 82 genes related to the Nrg4-ErbB pathway in liver and VAT was not significantly different between NAFL, NASH or obese controls. Conclusion Our study does not support a role for Nrg4 in the pathophysiology of human NAFLD.

Summary The fungus Aspergillus fumigatus is ubiquitous in nature and the most common cause of invasive pulmonary aspergillosis (IPA) in patients with a compromised immune system. The development of IPA in patients under immunosuppressive treatment or in patients with primary immunodeficiency demonstrates the importance of the host immune response in controlling aspergillosis. However, study of the host-microbe interaction has been hampered by the lack of tools for their non-invasive assessment. We developed a methodology to study the response of the host's immune system against IPA longitudinally in vivo by using fluorine-19 magnetic resonance imaging (19F MRI). We showed the advantage of a perfluorocarbon-based contrast agent for the in vivo labeling of macrophages and dendritic cells, permitting quantification of pulmonary inflammation in different murine IPA models. Our findings reveal the potential of 19F MRI for the assessment of rapid kinetics of innate immune response against IPA and the permissive niche generated through immunosuppression., Graphical Abstract, Highlights • Host-pathogen immune response is visualized in vivo and quantified against IPA • Modified PFC-based nanoparticles were used for in vivo labeling of immune cells • Clinical immunosuppression depict dynamic immune response upon fungal challenge • 19F MRI showed follow-up of labeled immune cells in individual animals over time, Infection Control in Health Technology; Medical Imaging; Mycology

Tracking the autoreactive T-cell migration in the pancreatic region after labeling with fluorinated nanoparticles (1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-N-[3-(2-pyridyldithio)propionate]-perfluoro-15-crown-5-ether nanoparticles, PDP-PFCE NPs) in a diabetic murine model using 19F MRI. Synthesis of novel PDP-PFCE fluorine tracer was performed for in vitro labeling of T cells. Labeling conditions were optimized using different PDP-PFCE NPs concentrations. For in vivo 19F MRI, mice were longitudinally followed after adoptive transfer of activated, autoreactive, labeled T cells in NOD.SCID mice. Established MR protocols were used for challenging T cell labeling to track inflammation in a model of diabetes after successful labeling of CD4+ and CD8+ T cells with PDP-PFCE NPs. However, T cells were difficult to be detected in vivo after their engraftment in animals. We showed successful in vitro labeling of T cells using novel fluorinated liposomal nanoparticles. However, insufficient and slow accumulation of labeled T cells and subsequent T cell proliferation in the pancreatic region remains as limitations of in vivo cell imaging by 19F MRI.

Severe alcoholic hepatitis is the most severe form of alcohol-related liver disease. Corticosteroids remain the first choice of treatment. However, they are only effective in a subset of patients and are associated with an increased infection risk. Furthermore, nonresponders to corticosteroids have a poor prognosis with a mortality of 70% over 6 months. As such, there is a high need for a more personalized use of corticosteroids and the development and identification of alternative therapeutic strategies. In this review, we summarize the recent and ongoing randomized controlled trials concerning the treatment of severe alcoholic hepatitis. ispartof: CURRENT OPINION IN PHARMACOLOGY vol:60 pages:91-101 ispartof: location:England status: published

The pathogenesis of type 1 diabetes (T1D) involves presentation of islet-specific self-antigens by dendritic cells (DCs) to autoreactive T cells, resulting in the destruction of insulin-producing pancreatic beta cells. We aimed to study the dynamic homing of diabetes-prone DCs to the pancreas and nearby organs with and without induction of pancreatic stress in a T1D susceptible model of repeated streptozotocin (STZ) injection.In vitro labeling of activated bone marrow-derived DCs (BMDCs) from NOD (Nonobese diabetes) mice was performed using zonyl perfluoro-15-crown-5-ether nanoparticles (ZPFCE-NPs). Internalization of particles was confirmed by confocal microscopy. Two groups of NOD.SCID (nonobese diabetic/severe combined immunodeficiency) mice with (induced by low dose STZ administration) or without pancreatic stress were compared. Diabetogenic BMDCs loaded with BDC2.5 mimotope were pre-labeled with ZPFCE-NPs and adoptively transferred into mice. Longitudinal in vivo fluorine MRI (In vitro flow cytometry and confocal microscopy confirmed high uptake of nanoparticles in BMDCs during the process of maturation. Migration/homing of activated and ZPFCE-NP- labeled BMDCs to different organs was monitored and quantified longitudinally, showing highest cell density in pancreas at 48-h time-point. Based onWe showed the potential of

Bovine African Trypanosomosis is an infectious parasitic disease affecting livestock productivity and thereby impairing the economic development of Sub-Saharan Africa. The most important trypanosome species implicated is T. congolense, causing anemia as most important pathological feature. Using murine models, it was shown that due to the parasite’s efficient immune evasion mechanisms, including (i) antigenic variation of the variable surface glycoprotein (VSG) coat, (ii) induction of polyclonal B cell activation, (iii) loss of B cell memory and (iv) T cell mediated immunosuppression, disease prevention through vaccination has so far been impossible. In trypanotolerant models a strong, early pro-inflammatory immune response involving IFN-γ, TNF and NO, combined with a strong humoral anti-VSG response, ensures early parasitemia control. This potent protective inflammatory response is counterbalanced by the production of the anti-inflammatory cytokine IL-10, which in turn prevents early death of the host from uncontrolled hyper-inflammation-mediated immunopathologies. Though at this stage different hematopoietic cells, such as NK cells, T cells and B cells as well as myeloid cells (i.e. alternatively activated myeloid cells (M2) or Ly6c- monocytes), were found to produce IL-10, the contribution of non-hematopoietic cells as potential IL-10 source during experimental T. congolense infection has not been addressed. Here, we report for the first time that during the chronic stage of T. congolense infection non-hematopoietic cells constitute an important source of IL-10. Our data shows that hepatocyte-derived IL-10 is mandatory for host survival and is crucial for the control of trypanosomosis-induced inflammation and associated immunopathologies such as anemia, hepatosplenomegaly and excessive tissue injury., Author summary Bovine African Trypanosomosis is a parasitic disease of veterinary importance that adversely affects the public health and economic development of sub-Saharan Africa. The most important trypanosome species implicated is T. congolense, causing anemia as most important pathological feature and major cause of death. Using murine models, it was shown that the disease is characterized by a well-timed and balanced production of pro-inflammatory cytokine promoting factors followed by an anti-inflammatory response, involving IL-10. The latter is required to attenuate infection-associated pathogenicity and to prevent early host death from uncontrolled hyper-inflammation mediated immunopathologies. However, the cellular source of IL-10 in vivo and the window within which these cells exert their function during the course of African trypanosomiasis remain poorly understood, which hampers the design of effective therapeutic strategies. Using a T. congolense infection mouse model, relevant for bovine trypanosomosis, we demonstrate that during the chronic stage of infection hepatocyte-derived IL-10, but not myeloid cell-derived IL-10, regulates the main infection-associated immunopathologies and ultimately mediates host survival. Hence, strategies that tilt the balance of hepatocyte cytokine production in favor of IL-10 could majorly impact the wellbeing and survival of T. congolense-infected animals. Given the unmet medical need for this parasite infection, our findings offer promise for improved treatment protocols in the field.

Obesity is a widespread health condition, which can lead to the development of metabolic disorders, such as type 2 diabetes mellitus, nonalcoholic fatty liver disease and cardiovascular diseases. Obesity is marked by the excessive deposition of fat in adipose tissue sites combined with chronic low-grade inflammation. Within this clinical setting, it is well established that adipose tissue macrophages exhibit prominent roles in regulating inflammation and metabolism. However, aside from these well-established roles, the involvement of microenvironmental cues as well as underlying cellular metabolism in driving immunological fate decisions within macrophages are poorly understood. Here we aim to map the different adipose tissue-derived macrophage subsets, together with their metabolic and functional profiles. Finally, we discuss their potential contribution during homeostasis and disease progression associated with obesity. ispartof: Immunometabolism vol:2 issue:1 pages:1-15 status: published

// Erminia Romano 1 , Nicole Rufo 1 , Hannelie Korf 2, 3 , Chantal Mathieu 3 , Abhishek D. Garg 1 and Patrizia Agostinis 1 1 Laboratory for Cell Death Research and Therapy (CDRT), Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium 2 Laboratory of Hepatology, Department of Chronic Diseases, Metabolism and Ageing (CHROMETA), KU Leuven, Leuven, Belgium 3 Laboratory of Clinical and Experimental Endocrinology (CEE), Department of Chronic Diseases, Metabolism and Ageing (CHROMETA), KU Leuven, Leuven, Belgium Correspondence to: Patrizia Agostinis, email: patrizia.agostinis@kuleuven.be Abhishek D. Garg, email: abhishek.garg@kuleuven.be Keywords: cancer; immunogenic cell death; phagocytosis; macrophage; anticancer vaccination Received: December 23, 2017 Accepted: February 27, 2018 Published: April 03, 2018 ABSTRACT The hypoxia responsive protein BNIP3, plays an important role in promoting cell death and/or autophagy, ultimately resulting in a cancer type-dependent, tumour-enhancer or tumour-suppressor activity. We previously reported that in melanoma cells, BNIP3 regulates cellular morphology, mitochondrial clearance, cellular viability and maintains protein expression of CD47, a pro-cancerous, immunosuppressive 'don't eat me' signal. Surface exposed CD47 is often up-regulated by cancer cells to avoid clearance by phagocytes and to suppress immunogenic cell death (ICD) elicited by anticancer therapies. However, whether melanoma-associated BNIP3 modulates CD47-associated immunological effects or ICD has not been explored properly. To this end, we evaluated the impact of the genetic ablation of BNIP3 (i.e. BNIP3 KD ) in melanoma cells, on macrophage-based phagocytosis, polarization and chemotaxis. Additionally, we tested its effects on crucial determinants of chemotherapy-induced ICD (i.e. danger signals), as well as in vivo anticancer vaccination effect. Interestingly, loss of BNIP3 reduced the expression of CD47 both in normoxic and hypoxic conditions while macrophage phagocytosis and chemotaxis were accentuated only when BNIP3 KD melanoma cells were exposed to hypoxia. Moreover, when exposed to the ICD inducer mitoxantrone, the loss of melanoma cell-associated BNIP3 did not alter apoptosis induction, but significantly prevented ATP secretion and reduced phagocytic clearance of dying cells. In line with this, prophylactic vaccination experiments showed that the loss of BNIP3 tends to increase the intrinsic resistance of B16-F10 melanoma cells to ICD-associated anticancer vaccination effect in vivo . Thus, normoxic vs. hypoxic and live vs. dying cell contexts influence the ultimate immunomodulatory roles of melanoma cell-associated BNIP3.

Mycobacterium tuberculosis is one of the most successful pathogens known, having infected more than a third of the global population. An important strategy for intracellular survival of pathogenic mycobacteria relies on their capacity to resist delivery to lysosomes, instead surviving within macrophage phagosomes. Several factors of both mycobacterial and host origin have been implicated in this process. However, whether or not this strategy is employed in vivo is not clear. Here we show that in vivo, following intravenous infection, M. tuberculosis and Mycobacterium bovis BCG initially survived by resisting lysosomal transfer. However, after prolonged infection the bacteria were transferred to lysosomes yet continued to proliferate. A M. bovis BCG mutant lacking protein kinase G (PknG), that cannot avoid lysosomal transfer and is readily cleared in vitro, was found to survive and proliferate in vivo. The ability to survive and proliferate in lysosomal organelles in vivo was found to be due to an altered host environment rather than changes in the inherent ability of the bacteria to arrest phagosome maturation. Thus, within an infected host, both M. tuberculosis and M. bovis BCG adapts to infection-specific host responses. These results are important to understand the pathology of tuberculosis and may have implications for the development of effective strategies to combat tuberculosis.

Aims/hypothesis Hypoxia in the initial days after islet transplantation leads to considerable loss of islet mass and contributes to disappointing outcomes in the clinical setting. The aim of the present study was to investigate whether co-transplantation of human non-endothelial bone marrow-derived multipotent adult progenitor cells (MAPCs), which are non-immunogenic and can secrete angiogenic growth factors during the initial days after implantation, could improve islet engraftment and survival. Methods Islets (150) were co-transplanted, with or without human MAPCs (2.5 × 105) as separate or composite pellets, under the kidney capsule of syngeneic alloxan-induced diabetic C57BL/6 mice. Blood glucose levels were frequently monitored and IPGTTs were carried out. Grafts and serum were harvested at 2 and 5 weeks after transplantation to assess outcome. Results Human MAPCs produced high amounts of angiogenic growth factors, including vascular endothelial growth factor, in vitro and in vivo, as demonstrated by the induction of neo-angiogenesis in the chorioallantoic membrane assay. Islet–human MAPC co-transplantation as a composite pellet significantly improved the outcome of islet transplantation as measured by the initial glycaemic control, diabetes reversal rate, glucose tolerance and serum C-peptide concentration compared with the outcome following transplantation of islets alone. Histologically, a higher blood vessel area and density in addition to a higher vessel/islet ratio were detected in recipients of islet–human MAPC composites. Conclusions/interpretation The present data suggest that co-transplantation of mouse pancreatic islets with human MAPCs, which secrete high amounts of angiogenic growth factors, enhance islet graft revascularisation and subsequently improve islet graft function. Electronic supplementary material The online version of this article (doi:10.1007/s00125-016-4120-3) contains peer-reviewed but unedited supplementary material, which is available to authorised users.

ispartof: Frontiers in Immunology vol:10 pages:1-3 ispartof: location:Switzerland status: published

This article contains data related to the inflammatory cytokine and investigated pathways involved in bacterial clearance reported in "Airway infection with Nontypeable Haemophilus influenzae is more rapidly eradicated in vitamin D deficient mice" (Serré et al., 2018) [1]. Vitamin D deficient or sufficient mice were oropharyngeally instilled with 106 NTHi and sacrificed at 4, 8, 24 and 72 h post-infection. We measured proinflammatory cytokines (KC, TNF-α, IL-1β, IL6 and MCP-1) markers of bacterial clearance pathways (myeloid peroxidase, nitric oxide, complement C5a and immunoglobulin A) in bronchoalveolar fluid (BALF) during infection and mRNA expression levels of innate immune defense mechanism markers (mucin glycoproteins, pathogen recognitions receptor TLR2 and TLR4, antimicrobial peptides SLPI, REG3γ, lysozyme, BD-1, BD-2, BD-3 and surfactant proteins SP-A and SP-D) in lung homogenate. Finally, genomic DNA of NTHi (protein D) measured in lung homogenate was used as an indicator of NTHi invasion of alveolar macrophages or epithelial cells. ispartof: DATA IN BRIEF vol:22 pages:703-708 ispartof: location:Netherlands status: published

Background:Commonly used islet transplantation protocols experiencesignificant islet injury and graft loss; therefore new methods to support thelong-term benefits of this treatment are needed. Recent studies have shownthat non-endothelial bone marrow-derived multipotent adult progenitor cells(MAPC) possess significant immune-modulating abilities and can secreteangiogenic molecules, which could make them ideal in islet transplantationprocedures to improve graft outcome.Methods:Islets (150) were co-transplanted with or without human MAPC(250 000), as separate or composite pellets, under the kidney capsule ofsyngeneic alloxan-induced diabetic C57BL/6 mice. Blood glucose levels werefrequently monitored and intraperitoneal glucose tolerance tests were carriedout. Grafts and serum were harvested at 2 and 5 weeks after transplantation.Results:Human MAPC were able to produce several angiogenic growthfactors, among which vascular endothelial growth factor (VEGF) is one of themost important, and to induce angiogenesis in thein vivochorioallantoicmembrane (CAM) assay. Islet-human MAPC co-transplantation particularly asa composite pellet significantly improved the outcome of islet transplantation asmeasured by the initial glycemic control, diabetes reversal rate, glucosetolerance, and serum C-peptide concentration compared with transplantationof islets alone. Likewise islet-human MAPC recipients had increased intra-graftCD31 gene expression levels compared to islet alone recipients, suggestingstable blood vessel formation. Indeed, significantly more blood vessel area anddensity in addition to higher vessel/islet ratio were detected with islets-humanMAPC composites, which suggests that direct contact with human MAPC ismore beneficial than indirect contact for mouse islets.Conclusions:The present data encourage the use of human MAPC in islettransplantation protocols. Our results demonstrate the improvement of isletgraft function. (Less)

ispartof: Hepatology vol:66 issue:5 pages:1689-1691 ispartof: location:United States status: published

Chronic obstructive pulmonary disease (COPD), which is characterized by an excessive inflammatory response of the airways, is often complicated by exacerbations. Vitamin D deficiency has been associated with an increased risk for COPD and may predispose COPD patients to a higher exacerbation rate, particularly during smoking. In the current study, we investigated the effect of vitamin D deficiency and cigarette smoke (CS)-exposure on lung inflammation and bacterial clearance after an acute infection with Nontypeable Haemophilus influenzae (NTHi). Vitamin D deficient or sufficient mice were exposed to nose-only CS or ambient air for 6 weeks and oropharyngeally instilled with 106 NTHi. Residual viable NTHi were measured at different time points post-infection. Mechanisms of bacterial clearance (e.g. phagocytosis, pattern recognition receptors, antimicrobial peptides, surfactant proteins and mucin) and lung remodeling (e.g. metalloproteinases, MMP’s) were assessed. Although smoking resulted in reduced phagocytosis capacity of macrophages and neutrophils, bacterial clearance was similar to control mice. By contrast and independent of smoking, bacterial clearance was significantly accelerated in vitamin D deficient mice already from 24 h post-infection (p = 0.0087). This faster and complete eradication was associated with a more rapid resolution of cytokines and neutrophils 72 h post-infection and dominated by an upregulation of cathelicidin-related antimicrobial peptide (CRAMP) mRNA during infection (p = 0.026). However, vitamin D deficiency also resulted in more MMP12 protein in broncho-alveolar lavage and a shift in mRNA expression of MMP12/TIMP1 (p = 0.038) and MMP9/TIMP1 (p = 0.024) ratio towards more protease activity. Overall, vitamin D deficient mice resolved NTHi infection faster with a faster resolution of local lung inflammation, possibly through upregulation of CRAMP. This was associated with a disruption of the protease/anti-protease balance, which may potentially scale towards a higher extracellular matrix breakdown.

Objective Acute-on-chronic liver failure (ACLF) is associated with dysfunctional circulating monocytes whereby patients become highly susceptible to bacterial infections. Here, we identify the pathways underlying monocyte dysfunction in ACLF and we investigate whether metabolic rewiring reinstates their phagocytic and inflammatory capacity. Design Following phenotypic characterisation, we performed RNA sequencing on CD14 + CD16-monocytes from patients with ACLF and decompensated alcoholic cirrhosis. Additionally, an in vitro model mimicking ACLF patient-derived features was implemented to investigate the efficacy of metabolic regulators on monocyte function. Results Monocytes from patients with ACLF featured elevated frequencies of interleukin (IL)-10-producing cells, reduced human leucocyte antigen DR isotype (HLA-DR) expression and impaired phagocytic and oxidative burst capacity. Transcriptional profiling of isolated CD14 + CD16-monocytes in ACLF revealed upregulation of an array of immunosuppressive parameters and compromised antibacterial and antigen presentation machinery. In contrast, monocytes in decompensated cirrhosis showed intact capacity to respond to inflammatory triggers. Culturing healthy monocytes in ACLF plasma mimicked the immunosuppressive characteristics observed in patients, inducing a blunted phagocytic response and metabolic program associated with a tolerant state. Metabolic rewiring of the cells using a pharmacological inhibitor of glutamine synthetase, partially restored the phagocytic and inflammatory capacity of in vitro generated-as well as ACLF patient-derived monocytes. Highlighting its biological relevance, the glutamine synthetase/glutaminase ratio of ACLF patient-derived monocytes positively correlated with disease severity scores. Conclusion In ACLF, monocytes feature a distinct transcriptional profile, polarised towards an immunotolerant state and altered metabolism. We demonstrated that metabolic rewiring of ACLF monocytes partially revives their function, opening up new options for therapeutic targeting in these patients., SCOPUS: ar.j, info:eu-repo/semantics/published

Objective: Cirrhosis is the common end-stage of any given chronic liver disease, developing after persistent destruction and regeneration of parenchymal liver cells. The associated architectural distortion increases the intrahepatic vascular resistance, leading to portal hypertension and systemic circulatory disorders. This study investigates the impact of the changing vascular resistances on the hepatic and global circulation hemodynamics during cirrhogenesis. Methods: Cirrhogenesis was revisited using the thioacetamide rat model (N = 20). Rats were sacrificed at weeks 0, 6, 12, and 18. For each time-point 3D vascular geometries were created by combining hepatic vascular corrosion casting with µCT imaging. Morphological quantification of the trees branching topology provided the input for a lobe-specific lumped parameter model of the liver that was coupled to a closed-loop model of the entire circulation of the rat. Hemodynamics were simulated in physiological and pathological circumstances. Results: The simulations showed the effect of the liver vascular resistances (driven by the hepatic venous resistance increase) on liver hemodynamics with portal hypertension observed after 12 weeks. The closed-loop model was further adapted to account for systemic circulatory compensation mechanisms and disorders frequently observed in cirrhosis and simulated their impact on the hepatic, systemic and pulmonary hemodynamics. Conclusion: The simulations explain how vascular changes due to cirrhosis severely disrupt both hepatic and global hemodynamics. Significance: This study is a priori the first to model the rat entire blood circulation during cirrhogenesis. Since it is able to simulate cirrhosis main characteristics, the model may be translated to humans for the assessment of liver interventions ispartof: IEEE Transactions on Biomedical Engineering vol:65 issue:10 pages:2311-2322 ispartof: location:United States status: published

BACKGROUND AND AIMS: We have recently shown that the mode of action of IgG1 anti-tumour necrosis factor [TNF] antibodies in inflammatory bowel disease [IBD] requires Fcγ-receptor [FcγR] engagement on macrophages. Here we examine the effect of Fcγ-receptor signalling by anti-TNF on macrophage IL-12/IL-23 secretion. METHODS: Cytokine production by human inflammatory macrophages was assessed at the level of RNA and protein. TNF-anti-TNF immune complex formation was determined by size-exclusion chromatography and signalling visualized by immunofluorescence. IL-12/IL-23p40 was measured in CD14+ lamina propria cells from IBD patients. RESULTS: Infliximab and adalimumab potently suppressed IL-12/IL-23 production by inflammatory macrophages, but Fab' fragment certolizumab did not. IL-12/IL-23 suppression depended on Syk activity and was mediated at the level of IL-12/IL-23p40 mRNA. Etanercept, a soluble TNF receptor fused to an Fc-region, did not inhibit IL-12/L-23 secretion, suggesting that the presence of an Fc-region was not sufficient. Infliximab and adalimumab formed immune complexes with soluble TNF whereas etanercept did not, suggesting that FcγR-mediated suppression of IL-12/IL-23 required the formation of immune complexes. Indeed, non-specific IgG1 immune complexes, but not uncomplexed IgG1, similarly suppressed IL-12/IL-23 secretion. Finally, infliximab significantly decreased IL-12/IL-23p40 production in myeloid cells isolated from the lamina propria of IBD patients. CONCLUSIONS: TNF-anti-TNF antibody immune complexes potently inhibit IL-12/IL-23 expression by inflammatory macrophages. Our data suggest that anti-TNFs and antibodies against IL-12/IL-23 may therefore have partially overlapping modes of action in patients with IBD. ispartof: JOURNAL OF CROHNS & COLITIS vol:12 issue:9 pages:1122-1130 ispartof: location:England status: published

Chronic obstructive pulmonary disease (COPD) is one of the most common respiratory diseases and a major cause of morbidity and mortality worldwide. Disturbed innate immune processes characterize the pathogenesis of COPD. Vitamin D deficiency is very common in COPD patients and has been associated with disease severity. Interestingly, mechanistic evidence from animal and in vitro studies has demonstrated important innate immunomodulatory functions of vitamin D, including anti-inflammatory, antioxidative, and antimicrobial functions. This review discusses in detail how the innate immunomodulatory functions of vitamin D may have therapeutic potential in COPD patients. The remaining challenges associated with vitamin D therapy in COPD patients are also discussed. ispartof: Journal of Pharmacology and Experimental Therapeutics vol:353 issue:2 pages:360-8 ispartof: location:United States status: published

Purpose of review Current data clearly support an interaction of vitamin D with cells of the immune system apart from its regulatory role in calcium homeostasis. The discovery that immune cells express the vitamin D receptor and are capable of metabolizing circulating 25-hydroxyvitamin D into its active form, 1,25-dihydroxyvitamin D, has revolutionized the field and suggested a regulatory role on both the innate and adaptive immune systems. Recent findings Of particular interest with respect to infectious diseases, 1,25-dihydroxyvitamin D has been shown to trigger the production of antimicrobial peptides with a direct pathogen-killing capacity. Interestingly, pathogen-derived components influence the key players in the vitamin D metabolizing pathway, further supporting such an interaction. Summary Here, we review the potential mechanisms of vitamin D in promoting the innate immune response against infectious agents and discuss the possible implications for such a response in the prevention of or the intervention in various infectious diseases.

The introduction of β-cell autoantigens via the gut through Lactococcus lactis (L. lactis) has been demonstrated to be a promising approach for diabetes reversal in NOD mice. Here we show that a combination therapy of low-dose anti-CD3 with a clinical-grade self-containing L. lactis, appropriate for human application, secreting human proinsulin and interleukin-10, cured 66% of mice with new-onset diabetes, which is comparable to therapy results with plasmid-driven L. lactis Initial blood glucose concentrations (

Macrophages contribute in the initiation and progression of insulitis during type 1 diabetes (T1D). However, the mechanisms governing their recruitment into the islets as well as the manner of retention and activation are incompletely understood. Here, we investigated a role for macrophage migration inhibitory factor (MIF) and its transmembrane receptor, CD74, in the progression of T1D. Our data indicated elevated MIF concentrations especially in long-standing T1D patients and mice. Additionally, NOD mice featured increased MIF gene expression and CD74+ leukocyte frequencies in the pancreas. We identified F4/80+ macrophages as the main immune cells in the pancreas expressing CD74 and showed that MIF antagonism of NOD macrophages prevented their activation-induced cytokine production. The physiological importance was highlighted by the fact that inhibition of MIF delayed the onset of autoimmune diabetes in two different diabetogenic T cell transfer models. Mechanistically, macrophages pre-conditioned with the MIF inhibitor featured a refractory capacity to trigger T cell activation by keeping them in a naïve state. This study underlines a possible role for MIF/CD74 signaling pathways in promoting macrophage-mediated inflammation in T1D. As therapies directed at the MIF/CD74 pathway are in clinical development, new opportunities may be proposed for arresting T1D progression. Fil: Korf, Hannelie. Katholikie Universiteit Leuven; Bélgica Fil: Breser, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; Argentina Fil: Van Hoeck, Jelter. Katholikie Universiteit Leuven; Bélgica Fil: Godoy, Gloria Janet. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; Argentina Fil: Cook, Dana P.. Katholikie Universiteit Leuven; Bélgica Fil: Stijlemans, Benoit. Vrije Unviversiteit Brussel; Bélgica Fil: De Smidt, Elien. Vrije Unviversiteit Brussel; Bélgica Fil: Moyson, Carolien. Katholikie Universiteit Leuven; Bélgica Fil: Cunha, João Paulo Monteiro Carvalho Mori. Katholikie Universiteit Leuven; Bélgica Fil: Rivero, Virginia Elena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; Argentina Fil: Gysemans, Conny. Katholikie Universiteit Leuven; Bélgica Fil: Mathieu, Chantal. Katholikie Universiteit Leuven; Bélgica