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Significance Chronic obstructive pulmonary disease (COPD) is an inflammatory disease characterized by limitation of expiratory airflow. Cellular and molecular pathways involved in disease pathogenesis are not completely defined. Our study reveals that metabolism and immune response cooperate in COPD pathogenesis and progression. COPD subjects with different disease stages showed progressive increase of systemic leptin, an adipose tissue-derived proinflammatory molecule, that, at high concentrations, impaired the capacity of T cells to engage in glycolysis and to generate regulatory T cells. Thus, the loss of these immunoregulatory circuits during COPD determined the hyperactivation of effector T cells that amplified inflammation, leading to progressive decline of lung function. Understanding these immunometabolic mechanisms can have important implications for monitoring COPD progression and for disease treatment., Chronic obstructive pulmonary disease (COPD) is an inflammatory condition associated with abnormal immune responses, leading to airflow obstruction. Lungs of COPD subjects show accumulation of proinflammatory T helper (Th) 1 and Th17 cells resembling that of autoreactive immune responses. As regulatory T (Treg) cells play a central role in the control of autoimmune responses and their generation and function are controlled by the adipocytokine leptin, we herein investigated the association among systemic leptin overproduction, reduced engagement of glycolysis in T cells, and reduced peripheral frequency of Treg cells in different COPD stages. These phenomena were also associated with an impaired capacity to generate inducible Treg (iTreg) cells from conventional T (Tconv) cells. At the molecular level, we found that leptin inhibited the expression of forkhead-boxP3 (FoxP3) and its splicing variants containing the exon 2 (FoxP3-E2) that correlated inversely with inflammation and weakened lung function during COPD progression. Our data reveal that the immunometabolic pathomechanism leading to COPD progression is characterized by leptin overproduction, a decline in the expression of FoxP3 splicing forms, and an impairment in Treg cell generation and function. These results have potential implications for better understanding the autoimmune-like nature of COPD and the pathogenic events leading to lung damage.

Simple Summary Down Syndrome, which is due to the presence of three copies of chromosome 21, always presents with mental retardation, possibly caused by defects in the development of neurons. In recent years, it has been shown that cells and tissues in Down syndrome manifest alterations in the function of mitochondria, the organelles that provide energy to cells. We hypothesized that mitochondrial dysfunction might contribute to the defect in neuronal cell development. To test this hypothesis, we generated a model of stem cells that, upon specific treatments, are capable of giving rise to neuronal cells, as evidenced by the synthesis of specific proteins. We observed that stem cells derived from Down syndrome individuals, after 21 days of growth in an artificial system, had an abnormal tendency to develop as glial cells, compared with control cells. As early as day 7 of culture, the trisomic cells also exhibited defects in mitochondrial function, such as anomalies in their calcium level, oxygen free radicals, oxygen consumption, and synthesis of ATP, a molecule that is critical in energy conversions. These results indicate that alterations in neuronal development and mitochondrial function occur early in this model, which we think is suitable for answering further questions. Abstract Background: The presence of mitochondrial alterations in Down syndrome suggests that it might affect neuronal differentiation. We established a model of trisomic iPSCs, differentiating into neural precursor cells (NPCs) to monitor the occurrence of differentiation defects and mitochondrial dysfunction. Methods: Isogenic trisomic and euploid iPSCs were differentiated into NPCs in monolayer cultures using the dual-SMAD inhibition protocol. Expression of pluripotency and neural differentiation genes was assessed by qRT-PCR and immunofluorescence. Meta-analysis of expression data was performed on iPSCs. Mitochondrial Ca2+, reactive oxygen species (ROS) and ATP production were investigated using fluorescent probes. Oxygen consumption rate (OCR) was determined by Seahorse Analyzer. Results: NPCs at day 7 of induction uniformly expressed the differentiation markers PAX6, SOX2 and NESTIN but not the stemness marker OCT4. At day 21, trisomic NPCs expressed higher levels of typical glial differentiation genes. Expression profiles indicated that mitochondrial genes were dysregulated in trisomic iPSCs. Trisomic NPCs showed altered mitochondrial Ca2+, reduced OCR and ATP synthesis, and elevated ROS production. Conclusions: Human trisomic iPSCs can be rapidly and efficiently differentiated into NPC monolayers. The trisomic NPCs obtained exhibit greater glial-like differentiation potential than their euploid counterparts and manifest mitochondrial dysfunction as early as day 7 of neuronal differentiation.

Metabolomics, lipidomics, and the study of cellular metabolism are gaining increasing interest particularly in the field of immunology, since the activation and effector functions of immune cells are profoundly controlled by changes in cellular metabolic asset. Among the different techniques that can be used for the evaluation of cellular metabolism, the Seahorse Extracellular Flux Analyzer allows the real time measurement of both glycolytic and mitochondrial respiration pathways in cells of interest, through the assessment of extracellular acidification and oxygen consumption rate. Metabolomics, on the other hand, is the high-throughput analysis of metabolites, i.e., the substrates, intermediates, and products of cellular metabolism, starting from biofluids, cells or tissues. The metabolome does not include lipids as their properties are different from water-soluble metabolites and are classified under the lipidome. Lipidomics analysis allows the identification and quantification of lipid species. Metabolomics and lipidomics are currently performed with mass-spectrometry coupled with liquid or gas chromatography (LC-MS or GC-MS) and/or nuclear-magnetic resonance (NMR). Here we describe the protocol for the evaluation of metabolic rate, metabolomics, and lipidomics in T cells, examining the detailed experimental approaches.

Metabolomics, lipidomics, and the study of cellular metabolism are gaining increasing interest particularly in the field of immunology, since the activation and effector functions of immune cells are profoundly controlled by changes in cellular metabolic asset. Among the different techniques that can be used for the evaluation of cellular metabolism, the Seahorse Extracellular Flux Analyzer allows the real time measurement of both glycolytic and mitochondrial respiration pathways in cells of interest, through the assessment of extracellular acidification and oxygen consumption rate. Metabolomics, on the other hand, is the high-throughput analysis of metabolites, i.e., the substrates, intermediates, and products of cellular metabolism, starting from biofluids, cells or tissues. The metabolome does not include lipids as their properties are different from water-soluble metabolites and are classified under the lipidome. Lipidomics analysis allows the identification and quantification of lipid species. Metabolomics and lipidomics are currently performed with mass-spectrometry coupled with liquid or gas chromatography (LC-MS or GC-MS) and/or nuclear-magnetic resonance (NMR). Here we describe the protocol for the evaluation of metabolic rate, metabolomics, and lipidomics in T cells, examining the detailed experimental approaches.

Regulatory T (Treg) cells are known to orchestrate the regulatory mechanisms aimed at suppressing pathological auto-reactive immune responses and are thus key in ensuring the maintenance of immune homeostasis. On the other hand, the presence of Treg cells with enhanced suppressive capability in a plethora of human cancers represents a major obstacle to an effective anti-cancer immune response. A relevant research effort has thus been dedicated to comprehend Treg cell biology, leading to a continuously refining characterization of their phenotype and function and unveiling the central role of metabolism in ensuring Treg cell fitness in cancer. Here we focus on how the peculiar biochemical characteristics of the tumor microenvironment actually support Treg cell metabolic activation and favor their selective survival and proliferation. Moreover, we examine the key metabolic pathways that may become useful targets of novel treatments directed at hampering tumor resident Treg cell proficiency, thus representing the next research frontier in cancer immunotherapy.

A report on a successful course organized by the EFIS-EJI Ruggero Ceppellini Advanced School of Immunology founded by Serafino Zappacosta

Introduction: Cryopyrin associated periodic syndromes (CAPS) are rare autoinflammatory disorders associated with dominantly gain-offunction mutations in the NLRP3 gene that result in overactivation of the inflammasome, increased secretion of interleukin (IL)-1beta and IL-18, and systemic inflammation. It has been reported that oligomeric particles of the adaptor ASC (apoptosis-associated Speck-like protein with a caspase-recruitment domain) are released together with IL-1beta and active caspase-1 subunits after activation of the inflammosome complex and that patients with CAPS show an increased serum concentration of ASC+ particles. Objectives: The diagnosis of CAPS is a critical factor due to both the lack of specific laboratory results and the sharing of similar clinical manifestations with other autoinflammatory diseases, our aim is to develop a simple assay to evaluate the levels of ASC particles in the serum of CAPS patients to provide novel biomarkers facilitating early disease diagnosis and able to monitor treatment responses. Methods: We developed an ELISA for the quantification of ASC particles in serum and plasma of normal and pathological subjects. We analysed samples from CAPS patients and from patients with autoimmune disorders (Multiple Sclerosis (MS), Type 1 Diabetes (T1D) and juvenile idiopathic arthritis), to confirm that ASC presence in the serum is not due to other chronic inflammatory processes characterizing autoimmunity. In addition, we also evaluated the concentration of ASC in the sera of TNF receptor–associated periodic syndrome (TRAPS) patients to reinforce the concept of specificity of this biomarker in CAPS patients and not in individuals suffering from others inflammatory disorders. Results: We observed that untreated CAPS patients are characterized by the presence of a significant higher amount of ASC particles when compared with healthy controls (HS) and with patients suffering from MS and T1D. This tendency was also evident in patients with arthritis and TRAPS even if the difference was not statistically significant due to the small number of samples. In addition there is a tendency through a reduction of ASC levels in CAPS patients after pharmacological treatment, which require future investigations. Conclusion: These data suggest that ELISA quantitation of ASC protein could represent a novel and additional strategy for the diagnosis and monitoring of CAPS.

Background: Regulatory T cells (Tregs) play a critical role in maintaining immune homeostasis. We investigated two main types of Tregs, the CD4+FOXP3+ and IL-10+ Tr1, in pediatric subjects with inflammatory bowel disease (IBD) both at diagnosis and after the clinical remission. Methods: Peripheral blood Tregs were analyzed in 16 children with Crohn's disease (CD), 19 with ulcerative colitis (UC), and 14 healthy controls (HC). Two cocktails of fluoresceinated antibodies were used to discriminate between CD4+FOXP3+ and Tr1. Results: We observed in both CD and UC groups a higher frequency of Tr1 at diagnosis compared to controls, which decreased at follow-up compared to diagnosis, in particular in UC. Similarly, in UC patients the percentage of CD4+FOXP3+ Tregs markedly decreased at follow-up compared to the same patients at diagnosis and compared to HC. The expression of CTLA-4 in CD4+FOXP3+ Tregs increased in both groups at clinical remission. Conclusion: This study shows that IBD children present at diagnosis an increased frequency of circulating Tregs, probably as a compensative reaction to tissue inflammation. During the clinical remission, the Treg frequency diminishes, and concomitantly, their activation status increases. Notwithstanding, the high Treg density at diagnosis is not sufficient to counteract the inflammation in the childhood IBD.

Background: Dominantly gain-of-function mutations in the NLRP3 gene lead to Cryopyrin associated periodic syndromes (CAPS) characterized by constitutive activation of the inflammasome, increased secretion of interleukin (IL)-1beta and IL-18, and systemic inflammation. IL-1beta and active caspase-1 subunits are released in the serum together with the oligomeric particles of the adaptor ASC (apoptosis-associated Speck-like protein with a caspase-recruitment domain) after activation of the inflammosome complex and, as a consequence, patients with CAPS show an increased serum concentration of ASC+ particles. Objectives: Patients suffering from CAPS are characterized by clinical manifestation similar to other autoinflammatory diseases. This phenomenon together with the lack of specific laboratory tests makes difficult the diagnosis of CAPS. In this context the development of a test for the evaluation of serum ASC levels could provide novel biomarkers facilitating early disease diagnosis and able to monitor treatment responses. Methods: We analysed, with a novel ELISA assay, the levels of ASC particles in serum and plasma of normal subjects, CAPS patients and patients with autoimmune disorders (Multiple Sclerosis (MS), Type 1 Diabetes (T1D) and juvenile idiopathic arthritis), to confirm that ASC presence in the serum is not due to other chronic inflammatory processes characterizing autoimmunity. To evaluate the specificity of this biomarker in CAPS patients and not in individuals suffering from others inflammatory disorders, we also analysed sera from TNF receptor–associated periodic syndrome (TRAPS) patients. Results: ASC particles were higher in untreated CAPS patients with respect to healthy controls and patients suffering from MS and T1D. This tendency was also evident in patients with arthritis and TRAPS even if the difference was not statistically significant due to the small number of samples. In addition after pharmacological treatment there is a tendency to be confirmed through a reduction of ASC levels in CAPS patients. Conclusion: These data suggest that ELISA quantitation of ASC protein could represent a novel and additional strategy for the diagnosis and monitoring of CAPS. Disclosure of Interests:: Fortunata Carbone: None declared, Teresa Micillo: None declared, Luca Cantarini: None declared, Maria Alessio: None declared, Alma Nunzia Olivieri: None declared, Maria Francesca Gicchino: None declared, Antonella Insalaco: None declared, Maria Cristina Maggio: None declared, Orso Maria Lucherini: None declared, Roberto Scarpioni: None declared, Matteo Piga: None declared, Maria Maddalena Angioni: None declared, Laura Obici: None declared, Antonella Simpatico: None declared, Pietro Leccese: None declared, Rita Consolini: None declared, Raffaele Manna: None declared, Paolo Sfriso: None declared, Sara Bindoli: None declared, Paola Galozzi: None declared, Ida Orlando: None declared, Sabrina Chiesa: None declared, Marco Gattorno Grant/research support from: MG has received unrestricted grants from Sobi and Novartis, Giuseppe Matarese Grant/research support from: Matarese reports research grants from Merck-Serono, Biogen Idec, Novartis and IBSA.

Background: Previous studies evidenced a link between metabolic dysregulation, inflammation, and neurodegeneration in multiple sclerosis (MS). Objectives: To explore whether increased adipocyte mass expressed as body mass index (BMI) and increased serum lipids influence cerebrospinal fluid (CSF) inflammation and disease severity. Methods: In this cross-sectional study, 140 consecutive relapsing-remitting (RR)-MS patients underwent clinical assessment, BMI evaluation, magnetic resonance imaging scan, and blood and CSF collection before any specific drug treatment. The CSF levels of the following cytokines, adipocytokines, and inflammatory factors were measured: interleukin (IL)-6, IL-13, granulocyte macrophage colony-stimulating factor, leptin, ghrelin, osteoprotegerin, osteopontin, plasminogen activator inhibitor-1, resistin, and Annexin A1. Serum levels of triglycerides, total cholesterol (TC), and high-density lipoprotein cholesterol (HDL-C) were assessed. Results: A positive correlation emerged between BMI and Expanded Disability Status Scale score. Obese RR-MS patients showed higher clinical disability, increased CSF levels of the proinflammatory molecules IL-6 and leptin, and reduced concentrations of the anti-inflammatory cytokine IL-13. Moreover, both the serum levels of triglycerides and TC/HDL-C ratio showed a positive correlation with IL-6 CSF concentrations. Conclusion: Obesity and altered lipid profile are associated with exacerbated central inflammation and higher clinical disability in RR-MS at the time of diagnosis. Increased adipocytokines and lipids can mediate the negative impact of high adiposity on RR-MS course.

Fatty liver disease is a serious complication of childhood obesity. Calorie-restricted regimen (RCR) is one of the effective therapy for this condition. Aim of the study was to evaluate the effect of lycopene-rich tomato sauce with oregano and basil extracts in obese children with fatty liver on RCR. 61 obese children with fatty liver were enrolled, 52 completed the study. A randomized cross over clinical trial was performed. Participants were assigned to RCR alone or with a supplement of lycopene-rich tomato juice for 60 days, subsequently, the groups were switched to the alternative regimen for the next 60 days. Reduction in BMI, HOMA-IR, cholesterol, triglycerides, liver size, and steatosis was more profound in tomato-supplemented group. Leptin decreased in both groups whereas adiponectin raised only after tomato supplementation. RCR is associated with the impaired engagement of T-cells glycolysis and proliferation, tomato-supplementation resulted in glycolytic metabolic activation of T-cells. Tomato juice ameliorates glucose and lipid metabolism in obese children, improve oxidative and inflammatory state and modulates the mitochondrial metabolism of T-cells contributing to a maintenance of a proper immune surveillance in children, impaired by RCR. The addition of tomato to RCR could be considered a protective and preventive support to obese child.

Reliable immunologic biomarkers able to monitor disease course during multiple sclerosis (MS) are still missing. We aimed at identifying possible immunometabolic biomarkers able to predict the clinical outcome in MS patients during treatment with interferon (IFN)-beta-1a. We measured in 45 relapsing-remitting (RR) MS patients, blood circulating levels of several immunometabolic markers, at enrolment, and correlated their levels to disease activity and progression over time. Higher levels of interleukin (IL)-6, soluble-CD40-ligand (sCD40L) and leptin at baseline associated with a higher relapse rate and a greater risk of experiencing at least one relapse in the following year. Higher values of soluble tumor necrosis factor receptor (sTNF-R) and leptin at baseline were predictive of a higher number of lesions in the following one-year of follow up. In conclusion, our data suggest that an immunometabolic profiling measuring IL-6, sCD40L, leptin and sTNF-R at baseline, could represent a useful tool to predict disease course in RRMS patients during treatment with IFN-beta-1a.

The filed that links immunity and metabolism is rapidly expanding. The adipose tissue, by secreting a series of immune regulators called adipokines, represents the common mediator linking metabolic processes and immune system functions. The dysregulation of adipokine secretion, occurring in obese individuals or in conditions of malnutrition or dietary restriction, affects the activity of immune cells resulting in inflammatory autoimmune responses or increased susceptibility to infectious diseases. Alterations of cell metabolism that characterize several autoimmune diseases strongly support the idea that the immune tolerance is also regulated by metabolic pathways. The comprehension of the molecular mechanisms underlying these alterations may lead to the development of novel therapeutic strategies to control immune cell differentiation and function in conditions of autoimmunity.