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Aims/hypothesis Antibodies specific to oxidative post-translational modifications (oxPTM) of insulin (oxPTM-INS) are present in most individuals with type 1 diabetes, even before the clinical onset. However, the antigenic determinants of such response are still unknown. In this study, we investigated the antibody response to oxPTM-INS neoepitope peptides (oxPTM-INSPs) and evaluated their ability to stimulate humoral and T cell responses in type 1 diabetes. We also assessed the concordance between antibody and T cell responses to the oxPTM-INS neoantigenic peptides. Methods oxPTM-INS was generated by exposing insulin to various reactive oxidants. The insulin fragments resulting from oxPTM were fractionated by size-exclusion chromatography further to ELISA and LC-MS/MS analysis to identify the oxidised peptide neoepitopes. Immunogenic peptide candidates were produced and then modified in house or designed to incorporate in silico-oxidised amino acids during synthesis. Autoantibodies to the oxPTM-INSPs were tested by ELISA using sera from 63 participants with new-onset type 1 diabetes and 30 control participants. An additional 18 fresh blood samples from participants with recently diagnosed type 1 diabetes, five with established disease, and from 11 control participants were used to evaluate, in parallel, CD4+ and CD8+ T cell activation by oxPTM-INSPs. Results We observed antibody and T cell responses to three out of six LC-MS/MS-identified insulin peptide candidates: A:12–21 (SLYQLENYCN, native insulin peptide 3 [Nt-INSP-3]), B:11–30 (LVEALYLVCGERGFFYTPKT, Nt-INSP-4) and B:21–30 (ERGFFYTPKT, Nt-INSP-6). For Nt-INSP-4 and Nt-INSP-6, serum antibody binding was stronger in type 1 diabetes compared with healthy control participants (p≤0.02), with oxidised forms of ERGFFYTPKT, oxPTM-INSP-6 conferring the highest antibody binding (83% binders to peptide modified in house by hydroxyl radical [●OH] and >88% to in silico-oxidised peptide; p≤0.001 vs control participants). Nt-INSP-4 induced the strongest T cell stimulation in type 1 diabetes compared with control participants for both CD4+ (p+ (p=0.049). CD4+ response to oxPTM-INSP-6 was also commoner in type 1 diabetes than in control participants (66.7% vs 27.3%; p=0.039). Among individuals with type 1 diabetes, the CD4+ response to oxPTM-INSP-6 was more frequent than to Nt-INSP-6 (66.7% vs 27.8%; p=0.045). Overall, 44.4% of patients showed a concordant autoimmune response to oxPTM-INSP involving simultaneously CD4+ and CD8+ T cells and autoantibodies. Conclusions/interpretation Our findings support the concept that oxidative stress, and neoantigenic epitopes of insulin, may be involved in the immunopathogenesis of type 1 diabetes. Graphical abstract

Context Poor glucose control has been associated with increased mortality in COVID-19 patients with type 1 diabetes (T1D). Objective This work aimed to assess the effect of prevaccination glucose control on antibody response to the SARS-CoV-2 vaccine BNT162b2 in T1D. Methods We studied 26 patients with T1D scheduled to receive 2 doses, 21 days apart, of BNT162b2, followed prospectively for 6 months with regular evaluation of SARS-CoV-2 antibodies and glucose control. Immunoglobulin G (IgG) to spike glycoprotein were assessed by enzyme-linked immunosorbent assay, and serum neutralization by a live SARS-CoV-2 assay (Vero E6 cells system). Glycated hemoglobin A1c (HbA1c) and continuous glucose monitoring (CGM), including time in range (TIR) and above range (TAR), were collected. The primary exposure and outcome measures were prevaccination glucose control, and antibody response after vaccination, respectively. Results Prevaccination HbA1c was unrelated to postvaccine spike IgG (r = −0.33; P = .14). Of note, the CGM profile collected during the 2 weeks preceding BNT162b2 administration correlated with postvaccine IgG response (TIR: r = 0.75; P = .02; TAR: r = −0.81; P = .008). Patients meeting the recommended prevaccination glucose targets of TIR (≥ 70%) and TAR (≤ 25%) developed stronger neutralizing antibody titers (P < .0001 and P = .008, respectively), regardless of HbA1c. Glucose control along the study time frame was also associated with IgG response during follow-up (TIR: r = 0.93; P < .0001; TAR: r = −0.84; P < .0001). Conclusion In T1D, glucose profile during the 2 weeks preceding vaccination is associated with stronger spike antibody binding and neutralization, highlighting a role for well-controlled blood glucose in vaccination efficacy.

Glioblastoma multiforme (GBM) is the most aggressive malignant brain tumor and is poorly susceptible to cytotoxic therapies. Amplification of the epidermal growth factor receptor (EGFR) and deletion of exons 2 to 7, which generates EGFR variant III (vIII), are the most common molecular alterations of GBMs that contribute to the aggressiveness of the disease. Recently, it has been shown that EGFR/EGFRvIII-targeted inhibitors enhance mitochondrial translocation by causing mitochondrial accumulation of these receptors, promoting the tumor drug resistance; moreover, they negatively modulate intrinsic mitochondria-mediated apoptosis by sequestering PUMA, leading to impaired apoptotic response in GBM cells. N6-isopentenyladenosine (i6A or iPA), a cytokinin consisting of an adenosine linked to an isopentenyl group deriving from the mevalonate pathway, has antiproliferative effects on numerous tumor cells, including GBM cells, by inducing cell death in vitro and in vivo. Here, we observed that iPA inhibits the mitochondrial respiration in GBM cells by preventing the translocation of EGFR/EGFRvIII to the mitochondria and allowing PUMA to interact with them by promoting changes in mitochondrial activity, thus playing a critical role in cell death. Our findings clearly demonstrate that iPA interferes with mitochondrial bioenergetic capacity, providing a rationale for an effective strategy for treating GBM.

Over the last few years, immune cell metabolism has become one of the most stimulating areas of investigation in the field of immunology. Compelling evidence has revealed that metabolic pathways are closely associated to cell functions and immune cells adopt defined metabolic programs to sustain their activity and respond to micro-environmental demands. It is now clear that alterations in cell metabolism can favour dysregulation typical of autoreactive immune cells, thus sustaining loss of immunological self-tolerance. In this short review, we highlight the main metabolic alterations associated with both innate and adaptive immune cells in autoimmune conditions, such as multiple sclerosis (MS) and type 1 diabetes (T1D). We also summarize recent findings reporting the use of pharmacological agents, which modulate the immunometabolism to possibly control immune responses during autoimmune disorders.

Aims/hypothesis: We assessed the levels of blood circulating immune checkpoint molecules (ICMs) at diagnosis of type 1 diabetes, and determined their association with the risk of developing an additional autoimmune disorder over time. Methods: Children with new-onset type 1 diabetes (n = 143), without biological and/or clinical signs of additional autoimmune disorders, and healthy children (n = 75) were enrolled, and blood circulating levels of 14 ICMs were measured. The children with type 1 diabetes were divided into two groups on the basis of the development of an additional autoimmune disease in the 5 years after diabetes onset. Differences in soluble ICM levels between the groups were assessed, and a Cox regression analysis was used to evaluate their association with the risk of development of an additional autoimmune disease over time. To validate the data, circulating ICMs were measured in an independent cohort of 60 children with new-onset type 1 diabetes stratified into two groups. Results: We found that the levels of circulating ICMs were significantly higher in children with new-onset diabetes compared with healthy children. Further, we observed that children with type 1 diabetes who developed a second autoimmune disease over time (T1D-AAD+ children) had higher levels of soluble ICMs than children with type 1 diabetes who did not (T1D-AAD− children). Cox regression models revealed that high circulating levels of CD137/4-1BB and PD-1 molecules at diabetes diagnosis were associated with the risk of developing an additional autoimmune disease in both type 1 diabetes cohorts. Conclusions/interpretation: Our findings suggest that soluble CD137/4-1BB and PD-1 molecules may be used as prognostic biomarkers in children with type 1 diabetes, and may pave the way for novel immunological screening at diabetes onset, allowing early identification of children at higher risk of developing other autoimmune conditions over time. Graphical abstract: [Figure not available: see fulltext.]

An unresolved issue in autoimmunity is the lack of surrogate biomarkers of immunological self-tolerance for disease monitoring. Here, we show that peripheral frequency of a regulatory T cell population, characterized by the coexpression of CD3 and CD56 molecules (TR3-56), is reduced in individuals with new-onset type 1 diabetes (T1D). In three independent T1D cohorts, we find that low frequency of circulating TR3-56 cells is associated with reduced beta-cell function and with the presence of diabetic ketoacidosis. Since autoreactive CD8+ T cells mediate disruption of insulin-producing beta cells1–3, we demonstrate that TR3-56 cells can suppress CD8+ T cell functions in vitro by reducing the levels of intracellular reactive oxygen species. The suppressive function, phenotype and transcriptional signature of TR3-56 cells are also altered in children with T1D. Together, our findings indicate that TR3-56 cells constitute a regulatory cell population that controls CD8+ effector functions, whose peripheral frequency may represent a traceable biomarker for monitoring immunological self-tolerance in T1D. Low numbers of circulating CD3+CD56+ regulatory T cells are associated with reduced beta-cell function and diabetic ketoacidosis in three separate cohorts of children with type 1 diabetes.

Chronic neuroinflammation is a key pathological hallmark of multiple sclerosis (MS) that suggests that resolution of inflammation by specialized proresolving molecules is dysregulated in the disease. Annexin A1 (ANXA1) is a protein induced by glucocorticoids that facilitates resolution of inflammation through several mechanisms that include an inhibition of leukocyte recruitment and activation. In this study, we investigated the ability of ANXA1 to influence T cell effector function in relapsing/remitting MS (RRMS), an autoimmune disease sustained by proinflammatory Th1/Th17 cells. Circulating expression levels of ANXA1 in naive-to-treatment RRMS subjects inversely correlated with disease score and progression. At the cellular level, there was an impaired ANXA1 production by CD4+CD25− conventional T and CD4+RORγt+ T (Th17) cells from RRMS subjects that associated with an increased migratory capacity in an in vitro model of blood brain barrier. Mechanistically, ANXA1 impaired monocyte maturation secondarily to STAT3 hyperactivation and potently reduced T cell activation, proliferation, and glycolysis. Together, these findings identify impaired disease resolution pathways in RRMS caused by dysregulated ANXA1 expression that could represent new potential therapeutic targets in RRMS.

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.

Significance: Type 1 diabetes (T1D) is characterized by the autoimmune destruction of the insulin secreting β-cells, with consequent aberrant blood glucose levels. Hyperglycemia is the common denominator for most of the chronic diabetic vascular complications, which represent the main cause of life reduction in T1D patients. For this disease, three interlaced medical needs remain: understanding the underlying mechanisms involved in pancreatic β-cell loss; identifying biomarkers able to predict T1D progression and its related complications; recognizing novel therapeutic targets. Recent Advances: Extracellular vesicles (EVs), released by most cell types, were discovered to contain a plethora of different molecules (including microRNAs) with regulatory properties, which are emerging as mediators of cell-to-cell communication at the paracrine and endocrine level. Recent knowledge suggests that EVs may act as pathogenic factors, and be developed into disease biomarkers and therapeutic targets in the context of several human diseases. Critical Issues: EVs have been recently shown to sustain a dysregulated cellular crosstalk able to exacerbate the autoimmune response in the pancreatic islets of T1D; moreover, EVs were shown to be able to monitor and/or predict the progression of T1D and the insurgence of vasculopathies. Future Directions: More mechanistic studies are needed to investigate whether the dysregulation of EVs in T1D patients is solely reflecting the progression of diabetes and related complications, or EVs also directly participate in the disease process, thus pointing to a potential use of EVs as therapeutic targets/tools in T1D.

Summary Human CD4+CD25hiFOXP3+ regulatory T (Treg) cells are key players in the control of immunological self-tolerance and homeostasis. Here, we report that signals of pseudo-starvation reversed human Treg cell in vitro anergy through an integrated transcriptional response, pertaining to proliferation, metabolism, and transmembrane solute carrier transport. At the molecular level, the Treg cell proliferative response was dependent on the induction of the cystine/glutamate antiporter solute carrier (SLC)7A11, whose expression was controlled by the nuclear factor erythroid 2-related factor 2 (NRF2). SLC7A11 induction in Treg cells was impaired in subjects with relapsing-remitting multiple sclerosis (RRMS), an autoimmune disorder associated with reduced Treg cell proliferative capacity. Treatment of RRMS subjects with dimethyl fumarate (DMF) rescued SLC7A11 induction and fully recovered Treg cell expansion. These results suggest a previously unrecognized mechanism that may account for the progressive loss of Treg cells in autoimmunity and unveil SLC7A11 as major target for the rescue of Treg cell proliferation.

Liquid biopsy, which allows the isolation of circulating cell-free (ccf) DNA from blood, is an emerging noninvasive tool widely used in oncology for diagnostic and prognosis purposes. Previous data have shown that serum cfDNA discriminates idiopathic pulmonary fibrosis (IPF) from other interstitial lung diseases. Our study aimed to measure plasma levels of ccfDNA in 59 consecutive therapy-naive and clinically stable IPF patients. The single nucleotide polymorphism (SNP) of the MUC5B gene promoter (rs35705950), associated with increased susceptibility of developing IPF, has been sought in plasma cfDNA and genomic DNA for comparison. Thirty-five age- and sex-matched healthy volunteers were recruited as the control group. Our results show that concentrations of small-size ccfDNA fragments were significantly higher in IPF patients than in controls and inversely correlated with lung function deterioration. Moreover, the median level of 104 ng/mL allowed discriminating patients with mild disease from those more advanced. The rs35705950 polymorphism was found in 11.8% of IPF patients and 8% of controls, with no differences. Complete concordance between ccfDNA and genomic DNA was detected in all control samples, while four out of seven IPF cases (57%) carrying the rs35705950 polymorphism were discordant from genomic DNA (7% of total IPF). Liquid biopsy is a suitable tool with optimistic expectations of application in the field of IPF. In analogy with cancer biology, finding some discrepancies between ccfDNA and genomic DNA in IPF patients suggests that the former may convey specific genetic information present in the primary site of the disease.

Contains fulltext : 232387.pdf (Publisher’s version ) (Closed access) There is a strong relationship between metabolic state and susceptibility to Mycobacterium tuberculosis (MTB) infection, with energy metabolism setting the basis for an exaggerated immuno-inflammatory response, which concurs with MTB pathogenesis. Herein, we show that controlled caloric restriction (CR), not leading to malnutrition, protects susceptible DBA/2 mice against pulmonary MTB infection by reducing bacterial load, lung immunopathology, and generation of foam cells, an MTB reservoir in lung granulomas. Mechanistically, CR induced a metabolic shift toward glycolysis, and decreased both fatty acid oxidation and mTOR activity associated with induction of autophagy in immune cells. An integrated multi-omics approach revealed a specific CR-induced metabolomic, transcriptomic, and proteomic signature leading to reduced lung damage and protective remodeling of lung interstitial tightness able to limit MTB spreading. Our data propose CR as a feasible immunometabolic manipulation to control MTB infection, and this approach offers an unexpected strategy to boost immunity against MTB.

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.

An unresolved issue in autoimmunity is the lack of surrogate biomarkers of immunological self-tolerance for disease monitoring. Here, we show that peripheral frequency of a regulatory T cell population, characterized by the co-expression of CD3 and CD56 molecules (TR3-56), is reduced in subjects with new-onset type 1 diabetes (T1D). In three independent T1D cohorts, we find that low frequency of circulating TR3-56 cells is associated with reduced β-cell function and with the presence of diabetic ketoacidosis. As autoreactive CD8+ T cells mediate disruption of insulin-producing β-cells1–3, we demonstrate that TR3-56 cells can suppress CD8+ T cell functions in vitro by reducing levels of intracellular reactive oxygen species. The suppressive function, phenotype and transcriptional signature of TR3-56 cells are also altered in T1D children. Together, our findings indicate that TR3-56 cells constitute a regulatory cell population that controls CD8+ effector functions, whose peripheral frequency may represent a traceable biomarker for monitoring immunological self-tolerance in T1D.

BackgroundMetabolic reprogramming towards aerobic glycolysis in cancer supports unrestricted cell proliferation, survival and chemoresistance. The molecular bases of these processes are still undefined. Recent reports suggest crucial roles for microRNAs. Here, we provide new evidence of the implication of miR-27a in modulating colorectal cancer (CRC) metabolism and chemoresistance.MethodsA survey of miR-27a expression profile in TCGA-COAD dataset revealed that miR-27a-overexpressing CRCs are enriched in gene signatures of mitochondrial dysfunction, deregulated oxidative phosphorylation, mTOR activation and reduced chemosensitivity. The same pathways were analysed in cell lines in which we modified miR-27a levels. The response to chemotherapy was investigated in an independent cohort and cell lines.ResultsmiR-27a upregulation in vitro associated with impaired oxidative phosphorylation, overall mitochondrial activities and slight influence on glycolysis. miR-27a hampered AMPK, enhanced mTOR signalling and acted in concert with oncogenes and tumour cell metabolic regulators to force an aerobic glycolytic metabolism supporting biomass production, unrestricted growth and chemoresistance. This latter association was confirmed in our cohort of patients and cell lines.ConclusionsWe disclose an unprecedented role for miR-27a as a master regulator of cancer metabolism reprogramming that impinges on CRC response to chemotherapy, underscoring its theragnostic properties.

Immune cell subsets and microRNAs have been independently proposed as type 1 diabetes (T1D) diagnostic and/or prognostic biomarkers. Here, we aimed to analyze the relationships between peripheral blood circulating immune cell subsets, plasmatic microRNAs, and T1D. Blood samples were obtained from both children with T1D at diagnosis and age-sex matched healthy controls. Then, immunophenotype assessed by flow cytometry was coupled with the quantification of 60 plasmatic microRNAs by quantitative RT-PCR. The associations between immune cell frequency, plasmatic microRNAs, and the parameters of pancreatic loss, glycemic control, and diabetic ketoacidosis were assessed by logistic regression models and correlation analyses. We found that the increase in specific plasmatic microRNAs was associated with T1D disease onset (let-7c-5p, let-7d-5p, let-7f-5p, let-7i-5p, miR-146a-5p, miR-423-3p, and miR-423-5p), serum C-peptide concentration (miR-142-5p and miR-29c-3p), glycated hemoglobin (miR-26a-5p and miR-223-3p) and the presence of ketoacidosis (miR-29c-3p) more strongly than the evaluated immune cell subset frequency. Some of these plasmatic microRNAs were shown to positively correlate with numbers of blood circulating B lymphocytes (miR-142-5p) and CD4+CD45RO+ (miR-146a-5p and miR-223-3p) and CD4+CD25+ cells (miR-423-3p and miR-223-3p) in children with T1D but not in healthy controls, suggesting a disease-specific microRNA association with immune dysregulation in T1D. In conclusion, our results suggest that, while blood co-circulating extracellular microRNAs and immune cell subsets may be biologically linked, microRNAs may better provide powerful information about T1D onset and severity.

Aims/hypothesis: We aimed to analyse the association between plasma circulating microRNAs (miRNAs) and the immunometabolic profile in children with type 1 diabetes and to identify a composite signature of miRNAs/immunometabolic factors able to predict type 1 diabetes progression. Methods: Plasma samples were obtained from children at diagnosis of type 1 diabetes (n = 88) and at 12 (n = 32) and 24 (n = 30) months after disease onset and from healthy control children with similar sex and age distribution (n = 47). We quantified 60 robustly expressed plasma circulating miRNAs by quantitative RT-PCR and nine plasma immunometabolic factors with a recognised role at the interface of metabolic and immune alterations in type 1 diabetes. Based on fasting C-peptide loss over time, children with type 1 diabetes were stratified into the following groups: those who had lost >90% of C-peptide compared with diagnosis level; those who had lost

No abstract available

Despite encouraging progresses achieved in the management of viral diseases, efficient strategies to counteract infections are still required. The current global challenge highlighted the need to develop a rapid and cost-effective strategy to counteract the SARS-CoV-2 pandemic. Lipid metabolism plays a crucial role in viral infections. Viruses can use the host lipid machinery to support their life cycle and to impair the host immune response. The altered expression of mevalonate pathway-related genes, induced by several viruses, assures survival and spread in host tissue. In some infections, statins, HMG-CoA-reductase inhibitors, reduce cholesterol in the plasma membrane of permissive cells resulting in lower viral titers and failure to internalize the virus. Statins can also counteract viral infections through their immunomodulatory, anti-inflammatory and anti-thrombotic effects. Beyond statins, interfering with the mevalonate pathway could have an adjuvant effect in therapies aimed at mitigating endothelial dysfunction and deregulated inflammation in viral infection. In this review we depicted the historical and current evidence highlighting how lipid homeostasis and mevalonate pathway targeting represents a valid approach to rapidly neutralize viruses, focusing our attention to their potential use as effective targets to hinder SARS-CoV-2 morbidity and mortality. Pros and cons of statins and Mevalonate-pathway inhibitors have been also dissected.

Along with the increase in life expectancy over the last century, the prevalence of age-related disorders, such as neurodegenerative diseases continues to rise. This is the case of Alzheimer's, Parkinson's, Huntington's diseases and Multiple sclerosis, which are chronic disorders characterized by neuronal loss in motor, sensory or cognitive systems. Accumulating evidence has suggested the presence of a strong correlation between metabolic changes and neurodegeneration. Indeed epidemiologic studies have shown strong associations between obesity, metabolic dysfunction, and neurodegeneration, while animal models have provided insights into the complex relationships between these conditions. In this context, hormones such as leptin, ghrelin, insulin and IGF-1 seem to play a key role in the regulation of neuronal damage, toxic insults and several other neurodegenerative processes. This review aims to presenting the most recent evidence supporting the crosstalk linking energy metabolism and neurodegeneration, and will focus on metabolic manipulation as a possible therapeutic tool in the prevention and treatment of neurodegenerative diseases.

Even if cancer specific biomarkers are present in peripheral blood of cancer patients, it is very difficult to detect them with conventional technology because of their low concentration. A potential cancer biomarker is the HMGA1b protein, whose overexpression is a feature of several human malignant neoplasias. By taking advantage of the surface plasmon resonance (SPR) phenomenon, we realized a specific nano/technology-based assay for cancer detection. More in details, anti-HMGA1b monoclonal antibodies, whose affinity was previously defined by ELISA, were immobilized onto metallic surfaces to develop a direct SPR-based assay. After having analyzed blood samples from colorectal cancer patients and healthy people for the presence of HMGA1b, we observed a 2-fold increase of the HMGA1b levels in the blood of cancer patients with respect to the healthy control people. We conclude that the set-up technology might allow to detect a tumoral mass through the evaluation of HMGA1b protein blood levels.

Metabolic alterations leading to overactivation of nutrient-energy-sensing pathways have been linked to altered immunological self-tolerance. Now, Zhang and colleagues (Immunity, 2019) have identified a key role for high glucose consumption in exacerbating autoimmunity in mice via induction of T helper (Th)17 cells. This reveals a novel mechanism underlying effects of diet during autoimmunity development with major translational implications.

Metabolic reprogramming towards aerobic glycolysis in cancer supports unrestricted cell proliferation, survival and chemoresistance. The molecular bases of these processes are still undefined. Recent reports suggest crucial roles for microRNAs. Here, we provide new evidence of the implication of miR-27a in modulating colorectal cancer (CRC) metabolism and chemoresistance.A survey of miR-27a expression profile in TCGA-COAD dataset revealed that miR-27a-overexpressing CRCs are enriched in gene signatures of mitochondrial dysfunction, deregulated oxidative phosphorylation, mTOR activation and reduced chemosensitivity. The same pathways were analysed in cell lines in which we modified miR-27a levels. The response to chemotherapy was investigated in an independent cohort and cell lines.miR-27a upregulation in vitro associated with impaired oxidative phosphorylation, overall mitochondrial activities and slight influence on glycolysis. miR-27a hampered AMPK, enhanced mTOR signalling and acted in concert with oncogenes and tumour cell metabolic regulators to force an aerobic glycolytic metabolism supporting biomass production, unrestricted growth and chemoresistance. This latter association was confirmed in our cohort of patients and cell lines.We disclose an unprecedented role for miR-27a as a master regulator of cancer metabolism reprogramming that impinges on CRC response to chemotherapy, underscoring its theragnostic properties.

Increasing pancreatic β-cell proliferation in autoimmune type 1 diabetes (T1D) might restore β-cell mass but would be predicted to exacerbate islet inflammation. A study in Nature Metabolism, however, reports that boosting β-cell proliferation in mouse models of T1D is beneficial, preserving the immunological self-tolerance of islets through the induction of regulatory T cells.

Background Metabolic reprogramming is shaped to support specific cell functions since cellular metabolism controls the final outcome of immune response. Multiple sclerosis (MS) is an autoimmune disease resulting from loss of immune tolerance against central nervous system (CNS) myelin. Metabolic alterations of T cells occurring during MS are not yet well understood and their studies could have relevance in the comprehension of the pathogenetic events leading to loss of immune tolerance to self and to develop novel therapeutic strategies aimed at limiting MS progression. Methods and Results In this report, we observed that extracellular acidification rate (ECAR) and oxygen consumption rate (OCR), indicators of glycolysis and oxidative phosphorylation, respectively, were impaired during T cell activation in naive-to-treatment relapsing remitting (RR)MS patients when compared with healthy controls. These results were also corroborated at biochemical level by a reduced expression of the glycolitic enzymes aldolase, enolase 1, hexokinase I, and by reduction of Krebs cycle enzymes dihydrolipoamide- S -acetyl transferase (DLAT) and dihydrolipoamide-S-succinyl transferase (DLST). Treatment of RRMS patients with interferon beta-1a (IFN beta-1a) was able to restore T cell glycolysis and mitochondrial respiration as well as the amount of the metabolic enzymes to a level comparable to that of healthy controls. These changes associated with an up-regulation of the glucose transporter-1 (GLUT-1), a key element in intracellular transport of glucose. Conclusions Our data suggest that T cells from RRMS patients display a reduced engagement of glycolysis and mitochondrial respiration, reversible upon IFN beta-1a treatment, thus suggesting an involvement of an altered metabolism in the pathogenesis of MS.

Leptin is an adipocyte-derived hormone/cytokine that links nutritional status with neuroendocrine and immune functions. Initially described as an anti-obesity hormone, leptin has subsequently been shown to exert pleiotropic effects, being also able to influence haematopoiesis, thermogenesis, reproduction, angiogenesis, and more importantly immune homeostasis. As a cytokine, leptin can affect both innate and adaptive immunity, by inducing a pro-inflammatory response and thus playing a key role in the regulation of the pathogenesis of several autoimmune/inflammatory diseases. In this review, we discuss the most recent advances on the role of leptin as immune-modulator in mammals and we also provide an overview on its main functions in non-mammalian vertebrates.

Glycogen storage disease type 1b (GSD-1b) is an autosomal-recessive disease caused by mutation of glucose-6–phosphate transporter and characterized by altered glycogen/glucose homeostasis. A higher frequency of autoimmune diseases has been observed in GSD-1b patients, but the molecular determinants leading to this phenomenon remain unknown. To address this question, we investigated the effect of glucose-6–phosphate transporter mutation on immune cell homeostasis and CD4+ T cell functions. In GSD-1b subjects, we found lymphopenia and a reduced capacity of T cells to engage glycolysis upon TCR stimulation. These phenomena associated with reduced expression of the FOXP3 transcription factor, lower suppressive function in peripheral CD4+CD25+FOXP3+ regulatory T cells, and an impaired capacity of CD4+CD25− conventional T cells to induce expression of FOXP3 after suboptimal TCR stimulation. These data unveil the metabolic determinant leading to an increased autoimmunity risk in GSD-1b patients.

Ethylmercury thiosalicylate (thimerosal) is an organic mercury-based compound commonly used as an antimicrobial preservative that has been found to be neurotoxic. In contrast, histone deacetylases (HDACs) inhibition has been found to be neuroprotective against several environmental contaminants, such as polychlorinated biphenyls, di-2-ethylhexyl phthalate, and methylmercury. The aim of this study was to investigate the effect of HDAC inhibition on thimerosal-induced neurotoxicity in neuroblastoma cells and cortical neurons. Interestingly, we found that thimerosal, at 0.5 μM in SH-SY5Y cells and at 1 μM in neurons, caused cell death by activation of apoptosis, which was prevented by the HDAC class IIA inhibitor MC1568 but not the class I inhibitor MS275. Furthermore, thimerosal specifically increased HDAC4 protein expression but not that of HDACs 5, 6, 7, and 9. Western blot analysis revealed that MC1568 prevented thimerosal-induced HDAC4 increase. In addition, both HDAC4 knocking-down and MC1568 inhibited thimerosal-induced cell death in SH-SY5Y cells and cortical neurons. Importantly, intramuscular injection of 12 μg/kg thimerosal on postnatal days 7, 9, 11, and 15 increased HDAC4 levels in the prefrontal cortex (PFC), which decreased histone H4 acetylation in infant male rats, in parallel increased motor activity changes. In addition, coadministration of 40 mg/kg MC1568 (intraperitoneal injection) moderated the HDAC4 increase which reduced histone H4 deacetylation and caspase-3 cleavage in the PFC. Finally, open-field testing showed that thimerosal-induced motor activity changes are reduced by MC1568. These findings indicate that HDAC4 regulates thimerosal-induced cell death in neurons and that treatment with MC1568 prevents thimerosal-induced activation of caspase-3 in the rat PFC.

To find a common pathogenetic trait induced by polyQ-expanded proteins, we have used a conditional expression system in PC12 cells to tune the expression of these proteins and analyze the early and late consequences of their expression. We find that expression for 3 h of a polyQ-expanded protein stimulates cellular reactive oxygen species (ROS) levels and significantly reduces the mitochondrial electrochemical gradient. 24–36 h later, ROS induce DNA damage and activation of the checkpoint kinase, ATM. DNA damage signatures are reversible and persist as long as polyQ-expanded proteins are expressed. Transcription of neural and stress response genes is down-regulated in these cells. Selective inhibition of ATM or histone deacetylase rescues transcription and restores the expression of silenced genes. Eventually, after 1 week, the expression of polyQ-expanded protein also induces endoplasmic reticulum stress. As to the primary mechanism responsible for ROS generation, we find that polyQ-expanded proteins, including native Ataxin-2 and Huntingtin, are selectively sequestered in the lipid raft membrane compartment and interact with gp91, the membrane NADPH-oxidase subunit. Selective inhibition of NADPH oxidase or silencing of H-Ras signaling dissolves the aggregates and eliminates DNA damage. We suggest that targeting of the polyQ-expanded proteins to the lipid rafts activates the resident NADPH oxidase. This triggers a signal linking H-Ras, ROS, and ERK1/2 that maintains and propagates the ROS wave to the nucleus. This mechanism may represent the common pathogenetic signature of all polyQ-expanded proteins independently of the specific context or the function of the native wild type protein.

Summary There is a discrepancy between the in vitro anergic state of CD4 + CD25 hi FoxP3 + regulatory T (Treg) cells and their in vivo proliferative capability. The underlying mechanism of this paradox is unknown. Here we show that the anergic state of Treg cells depends on the elevated activity of the mammalian target of rapamycin (mTOR) pathway induced by leptin: a transient inhibition of mTOR with rapamycin, before T cell receptor (TCR) stimulation, made Treg cells highly proliferative in the absence of exogenous interleukin-2 (IL-2). This was a dynamic and oscillatory phenomenon characterized by an early downregulation of the leptin-mTOR pathway followed by an increase in mTOR activation necessary for Treg cell expansion to occur. These data suggest that energy metabolism, through the leptin-mTOR-axis, sets responsiveness of Treg cells that use this information to control immune tolerance and autoimmunity.

The c-Jun N-terminal kinase (JNK) has been shown to mediate tamoxifen-induced apoptosis in breast cancer cells. However, the downstream mediators of the JNK pathway linking tamoxifen to effectors of apoptosis have yet to be identified. Here we investigated whether c-Jun, the major nuclear target of JNK, plays a role in tamoxifen-induced apoptosis of SkBr3 breast cancer cells. We show that prior to DNA fragmentation and caspase 3/7 activation, cytotoxic concentrations of 4-hydroxytamoxifen (OHT) induced JNK-dependent phosphorylation of c-Jun at JNK sites previously shown to regulate c-Jun mediated apoptosis. Additionally, OHT induced ERK-dependent expression of c-Fos and transactivation of an AP-1-responsive promoter. In particular, the ectopic expression of dominant-negative constructs blocking either AP-1 activity or c-Jun N-terminal phosphorylation prevented DNA fragmentation following OHT treatment. Furthermore, both c-Fos expression and c-Jun N-terminal phosphorylation preceded OHT-dependent activation of caspase 3-7 in different types of tamoxifen-sensitive cancer cells, but not in OHT-resistant LNCaP prostate cancer cells. Taken together, our results indicate that the c-Jun/c-Fos AP-1 complex plays a pro-apoptotic role in OHT-treated cancer cells and suggest that pharmacological boosts of c-Jun activation may be useful in a combination therapy setting to sensitize cancer cells to tamoxifen-mediated cell death.

Methylmercury (MeHg) is a highly neurotoxic compound that, in adequate doses, can cause damage to the brain, including developmental defects and in severe cases cell death. The RE-1-silencing transcription factor (REST) has been found to be involved in the neurotoxic effects of environmental pollutants such as polychlorinated biphenyls (PCBs). In this study, we investigated the effects of MeHg treatment on REST expression and its role in MeHg-induced neurotoxicity in neuroblastoma SH-SY5Y cells. We found that MeHg exposure caused a dose- and time- dependent apoptotic cell death, as evidenced by the appearance of apoptotic hallmarks including caspase-3 processing and annexin V uptake. Moreover, MeHg increased REST gene and gene product expression. MeHg-induced apoptotic cell death was completely abolished by REST knockdown. Interestingly, MeHg (1. μM/24. h) increased the expression of REST Corepressor (Co-REST) and its binding with REST whereas the other REST cofactor mammalian SIN3 homolog A transcription regulator (mSin3A) was not modified. In addition, we demonstrated that the acetylation of histone protein H4 was reduced after MeHg treatment and was critical for MeHg-induced apoptosis. Accordingly, the pan-histone deacetylase inhibitor trichostatin-A (TSA) prevented MeHg-induced histone protein H4 deacetylation, thereby reverting MeHg-induced neurotoxic effect. Male mice subcutaneously injected with 10 mg/kg of MeHg for 10 days showed an increase in REST expression in the granule cell layer of the cerebellum together with a decrease in histone H4 acetylation. Collectively, we demonstrated that methylmercury exposure can cause neurotoxicity by activating REST gene expression and H4 deacetylation.

Summary Behcet's disease (BD) is a systemic inflammatory disease with a still unclear pathogenesis. Although several inflammatory molecules have been studied, current biomarkers are largely insensitive in BD and unable to predict disease progression and response to treatment. Our primary aim was to explore serum levels of soluble CD40 L (sCD40L), soluble intracellular adhesion molecule (sICAM-1), monocyte chemoattractant protein-1 (MCP-1), myeloperoxidase (MPO), leptin, resistin, osteoprotegerin (OPG), soluble type 1 tumour necrosis factor receptor (sTNFR), interleukin (IL)−6 and serum amyloid A (SAA) serum concentration in a cohort of 27 BD patients. The secondary aim was to evaluate potential correlations between the putative circulating biomarkers, demographic profile of patients, the status of disease activity, the specific organ involvement at the time of sample collection and different therapeutic regimens. Serum concentrations of sTNFR (P = 0·008), leptin (P = 0·0011), sCD40L (P < 0·0001) and IL-6 (P = 0·0154) were significantly higher in BD patients than in HC, while no difference was found in MCP-1, MPO and resistin serum levels. Moreover, we observed significantly higher sTNFR serum concentrations in BD patients presenting inactive disease than HC (P = 0·0108). A correlation between sTNFR and age was also found, with higher levels in patients over 40 years than HC (P = 0·0329). Although further research is warranted to elucidate the role of circulating biomarkers, some of that may contribute to the understanding of the physiopathology processes underlying BD activity and damage as well as to provide useful tools for prognostic purposes and a personalized treatment approach.

Pulmonary alveolar microlithiasis (PAM) is a rare diffuse lung disease characterised by the accumulation of calcium phosphate microliths within the alveoli. The causative mechanism of PAM has only recently been discovered, and involves a gene mutation of sodium phosphate co-transporter, which is expressed by alveolar epithelial cells. This mutation may have variable consequences on the clinical phenotype. However, pulmonary cell immune phenotyping in familial PAM has not previously been assessed. In the present article, the analysis of bronchoalveolar lavage fluid of two siblings with PAM diagnosis revealed a pattern of lymphocytic alveolitis with accumulation of CD8+ T-cells. The clonal complexity of this lymphocyte's population was assayed by spectratyping, which showed an oligoclonal accumulation of T-cells with a restricted variable beta T-cell receptor (TCR) gene usage. TCR analysis in peripheral blood lymphocytes revealed no abnormal patterns of T-lymphocytes. In the pulmonary alveolar microlithiasis familial cases reported, CD8-mediated maladaptive immune response may have taken place in the bronchoalveolar compartment. The relationship between this immune dysregulation and genetic background in pulmonary alveolar microlithiasis warrants further investigation.

The immune system is a highly integrated network of cells sensitive to a number of environmental factors. Interestingly, recent years have seen a dramatic increase in our understanding of how diet makes a crucial contribution to human health, affecting the immune system, secretion of adipocytokines and metabolic pathways. Recent experimental evidence indicates that diet and its components are able to profoundly influence immune responses, thus affecting the development of inflammatory and autoimmune diseases. This review aims to discuss some of the main topics concerning the impact of nutrients and their relative composition on immune cell development and function that may be particularly important for regulating the balance between inflammatory and tolerogenic processes. We also highlight the effects of diet on commensal bacteria and how changes in the composition of the microbiota alter intestinal and systemic immune homeostasis. Finally, we summarize the effects of dietary compounds on epigenetic mechanisms involved in the regulation of several immune related genes.

Monocytes are circulating precursors of the dendritic cell subset, professional antigen-presenting cells with a unique ability to initiate the innate and adaptive immune response. In this study, we have investigated the effects of wild-type Helicobacter pylori strains and their isogenic mutants with mutations in known bacterial virulence factors on monocytes and monocyte-derived dendritic cells. We show that H. pylori strains induce apoptosis of human monocytes by a mechanism that is dependent on the expression of a functional cag pathogenicity island. This effect requires an intact injection organelle for direct contact between monocytes and the bacteria but also requires a still-unidentified effector that is different from VacA or CagA. The exposure of in vitro-generated monocyte-derived dendritic cells to H. pylori stimulates the release of inflammatory cytokines by a similar mechanism. Of note is that dendritic cells are resistant to H. pylori -induced apoptosis. These phenomena may play a critical role in the evasion of the immune response by H. pylori , contributing to the persistence of the infection.

Summary Intracellular metabolic pathways dependent upon the mammalian target of rapamycin (mTOR) play a key role in immune-tolerance control. In this study, we focused on long-term mTOR-dependent immune-modulating effects in kidney transplant recipients undergoing conversion from calcineurin inhibitors (CNI) to mTOR inhibitors (everolimus) in a 1-year follow-up. The conversion to everolimus is associated with a decrease of neutrophils and of CD8+ T cells. In addition, we observed a reduced production of interferon (IFN)-γ by CD8+ T cells and of interleukin (IL)-17 by CD4+ T lymphocytes. An increase in CD4+CD25+ forkhead box protein 3 (FoxP3)+ [regulatory T cell [(Treg)] numbers was also seen. Treg increase correlated with a higher proliferation rate of this regulatory subpopulation when compared with the CD4+FoxP3− effector counterpart. Basal phosphorylation level of S6 kinase, a major mTOR-dependent molecular target, was substantially maintained in patients treated with everolimus. Moreover, oscillations in serum concentration of everolimus were associated with changes in basal and activation-dependent S6 kinase phosphorylation of CD4+ and CD8+ T cells. Indeed, T cell receptor (TCR) triggering was observed to induce significantly higher S6 kinase phosphorylation in the presence of lower everolimus serum concentrations. These results unveil the complex mTOR-dependent immune-metabolic network leading to long-term immune-modulation and might have relevance for novel therapeutic settings in kidney transplants.

CONTEXT: Anorexia nervosa (AN) is an excessive form of calorie restriction (CR) associated with pathological weight loss and alterations of the immune system. However, AN patients seem to be protected from common viral infections. OBJECTIVES: To investigate the metabolic and molecular adaptations induced by sustained extreme CR in the peripheral blood mononuclear cells (PBMCs) of patients with restrictive alimentary AN. DESIGN: Inflammatory cytokines and adipokines were measured in 15 young (age range, 15-24 years) AN female patients and 20 age-matched healthy controls. Isolated PBMCs were immunophenotyped by flow cytometry, and glycolysis and mitochondrial respiration were determined by measuring the extracellular acidification and oxygen consumption rate. Stress resistance to H2O2 and the antioxidant transcriptional profile of PBMCs and human fibroblasts incubated with sera from AN patients were also determined. RESULTS: Compared with controls, AN patients (BMI, 15.9±0.4kg/m(2)) had significantly fewer leucocytes, lymphocytes and NK cells, lower serum concentrations of leptin, IGF-1 and sTNFR1, and higher levels of adiponectin, sCD40L and sICAM-1 (p

During an immune response, T cell differentiation and function are tightly regulated to ensure protection against pathogens and prevent the autoimmune attack versus self-antigens. It is now established that cellular activation is coupled to profound changes in cellular metabolism. Indeed, pathways that control immune cell function and metabolism are intimately related, and different metabolic programs have been shown to control specific T cell fate. This review aims to provide an integrated view of T cell metabolism and of the molecular pathways controlling an appropriate T cell receptor (TCR) engagement. We describe here how different aspects of metabolism can influence T cell functions, focusing on the emerging role of the key metabolic pathways regulating T cell activation and their alterations in different autoimmune conditions. Manipulating these programs or their substrates could provide insights into mechanisms involved in inflammatory/autoimmune conditions, unveiling the potential for developing novel therapeutic approaches to treat these diseases.

Objective: We investigated the effect of glatiramer acetate (GA) on the modulation of immune cell subpopulations and serum levels of multiple immune/metabolic markers in patients with relapsing-remitting multiple sclerosis (RRMS) to understand whether the treatment with GA could induce a specific change in the immunometabolic asset of patients with RRMS. Material and methods: We performed an extensive peripheral blood immunophenotyping and measured serum levels of several parameters involved in the pathogenesis of RRMS and also relevant in the pathogenesis of metabolic syndrome and obesity such as leptin, soluble leptin-receptor (sLep-R), myeloperoxidase (MPO), soluble CD40 ligand (sCD40-L), soluble tumor necrosis factor-receptor (sTNF-R), monocyte chemoattractant protein 1 (MCP-1), soluble Inter-Cellular Adhesion Molecule-1 (sICAM-1) and osteoprotegerin (OPG), in 20 naïve-to-treatment RRMS patients and 20 healthy controls. We repeated these analyses over time at 6 and 12. months after starting GA treatment. Results: Our analysis showed that naïve-to-treatment RRMS patients had a lower number of CD16+CD56+ NK cells, CD19+ B cells, CD4+ T cells co-expressing the MHC class II activation marker HLA-DR (CD4+DR+) and naïve CD4+CD45RA+ T cells in basal conditions. GA treatment induced a specific and significant decrease of circulating CD19+ B cells. Naïve-to-treatment RRMS patients also showed a significantly higher number of CD4+ T cells with a memory phenotype (CD4+CD45RO+) whose peripheral frequency was not affected by GA treatment. These changes over time associated with a higher serum concentration of leptin and lower levels of MPO. GA treatment also reduced significantly the circulating levels of sCD40-L and sTNF-R overtime. Conclusions: Our data suggest that the clinical outcome of GA treatment is associated with changes in immune cell subpopulations and modulation of specific immunometabolic markers. These data add substantial evidence of the immune modulating effect of GA during RRMS and could be of relevance in understanding the pathogenesis of disease and its follow-up.