The cholesterol biosynthesis pathway regulates IL-10 expression in human Th1 cells

Expanding Human Breg for Cellular Therapy in Transplantation: Time for Translation

Regulatory B cells (Breg) are instrumental in protecting allografts in transplantation. Breg signatures are identified in operationally tolerant human kidney transplant recipients and can predict organ survival and acute rejection. Animal models of transplantation and autoimmunity support the use of Breg as an adoptive cellular therapy. Detailed mechanistic studies have identified multiple signaling pathways utilized by Breg in their induction, expansion, and downstream function. These preclinical studies provide the guiding principles, which will inform protocols by which to expand this crucial immunoregulatory population before clinical use. There is an urgent need for novel therapies to improve long-term transplant outcomes and to minimize immunosuppression-related morbidity including life-threatening infection and cancer. Systematic evaluation of the signals, which drive Breg expansion, will be key to transforming the as of yet unharnessed potential of this potent immunoregulatory cell. In this review, we explore the potential avenues of translating Breg subsets from cell culture at the laboratory bench to cell therapy at the patient's bedside. We will discuss the standardization of Breg phenotypes to aid in precursor population selection and quality control of a Breg-cell therapy product. We will evaluate avenues by which to optimize protocols to drive human Breg expansion to levels sufficient for cellular therapy. Finally, we will examine the steps required in process development including scalable culture systems and quality control measures to deliver a viable Breg-cell therapy product for administration to a transplant recipient.

Bacteroides sphingolipids promote anti-inflammatory responses through the mevalonate pathway

Sphingolipids derived from Bacteroides species are associated with changes in host inflammation and metabolic syndrome; however, the signaling mechanisms within host cells are unknown. We utilize outer membrane vesicles (OMVs) from wild-type and sphingolipid-deficient Bacteroides strains to understand how these lipids modulate host inflammation. Characterization of the lipidome of B. thetaiotaomicron OMVs revealed enrichment of dihydroceramide phosphoethanolamine (CerPE). OMVs deliver bacterial sphingolipids into host dendritic and epithelial cells, where a subset of lipids, including CerPE, stably persist. Similarly, B. thetaiotaomicron colonization results in sphingolipid persistence in murine tissues and host lipidome alterations that are not observed with the sphingolipid-deficient strain. OMVs induce a potent, sphingolipid-dependent interleukin-10 (IL-10) anti-inflammatory response in dendritic cells, which depends on mevalonate pathway activation. Adding a CerPE fraction to sphingolipid-deficient OMVs rescued IL-10 secretion, similarly dependent on mevalonate pathway activation. These data highlight the essential roles of sphingolipids in stimulating anti-inflammatory responses mediated by mevalonate pathway induction.

Inside job: Roles of intracellular C3

Our understanding of the complement system continues to grow beyond that of a liver-derived systemically operative mechanism of pathogen clearance to a central orchestrator of single-cell behavior and tissue biology. These expanded activities reflect the extrahepatic and local production of complement by many, if not most, cells, and the unexpected recent finding that complement also serves important physiological intracellular roles. The complement core component C3 has emerged as a particularly critical player in basic cell functions. Here, we provide an overview of the currently known forms and functions of intracellular C3 and the mechanisms that control it. We also discuss 2 emerging concepts as potential key areas for future exploration: intracellular C3 as a second layer of pathogen defense at host-environmental interfaces and "C3 licensing." We conclude by suggesting that the potential clinical implications surrounding perturbations in intracellular C3 activities should be explored better.

Atorvastatin attenuates intestinal mucositis induced by 5-fluorouracil in mice by modulating the epithelial barrier and inflammatory response

Chemotherapy-induced intestinal mucositis is a major side effect of cancer treatment. Statins are 3-hydroxy-3-methyl glutaryl coenzyme reductase inhibitors used to treat hypercholesterolemia and atherosclerotic diseases. Recent studies have demonstrated that atorvastatin (ATV) has antioxidant, anti-inflammatory, and resulting from the regulation of different molecular pathways. In the present study, we investigated the effects of ATV on intestinal homeostasis in 5-fluorouracil (5-FU)-induced mucositis. Our results showed that ATV protected the intestinal mucosa from epithelial damage caused by 5-FU mainly due to inflammatory infiltrate and intestinal permeability reduction, downregulation of inflammatory markers, such as Tlr4, MyD88, NF-κB, Tnf-a, Il1β, and Il6 dose-dependent. ATV also improved epithelial barrier function by upregulating the mRNA transcript levels of mucin 2 (MUC2), and ZO-1 and occludin tight junction proteins. The results suggest that the ATV anti-inflammatory and protective effects on 5-FU-induced mice mucositis involve the inhibition of the TLR4/MYD88/NPRL3/NF-κB, iNos, and caspase 3.

PCSK9 Manipulates Lipid Metabolism and the Immune Microenvironment in Cancer

Cancer remains the foremost cause of mortality on a global scale. Immunotherapy has yielded remarkable outcomes in the fight against cancer and is regarded as one of the most crucial and promising therapeutic modalities. PCSK9, a critical target for plasma lipids control, has been extensively and deeply studied in multiple diseases. Currently, the functions of PCSK9 in cancer, particularly its immunomodulatory role, have been progressively revealed. PCSK9 is capable of modulating a variety of immune response throughout tumor progression by orchestrating lipid metabolism. Moreover, PCSK9 governs the cell fate of diverse immune cells, such as inflammatory factor signals, MHC signals, and TCR signals. This review comprehensively summarizes the current state of knowledge regarding the role and underlying mechanisms of PCSK9 in tumorigenesis, progression, immune escape, and drug resistance.

An intracellular complement system drives metabolic and proinflammatory reprogramming of vascular fibroblasts in pulmonary hypertension

The complement system is central to the innate immune response, playing a critical role in proinflammatory and autoimmune diseases such as pulmonary hypertension (PH). Recent discoveries highlight the emerging role of intracellular complement, or the "complosome," in regulating cellular processes such as glycolysis, mitochondrial dynamics, and inflammatory gene expression. This study investigated the hypothesis that intracellular complement proteins C3, CFB, and CFD are upregulated in PH fibroblasts (PH-Fibs) and drive their metabolic and inflammatory states, contributing to PH progression. Our results revealed a pronounced upregulation of CFD, CFB, and C3 in PH-Fibs from human samples and bovine models, both in vivo and in vitro. The finding of elevated levels of C3 activation fragments, including C3b, C3d, and C3a, emphasized enhanced C3 activity. PH-Fibs exhibited notable metabolic reprogramming and increased levels of proinflammatory mediators such as MCP1, SDF1, IL-6, IL-13, and IL-33. Silencing CFD via shRNA reduced CFB activation and C3a production, while normalizing glycolysis, tricarboxylic acid (TCA) cycle activity, and fatty acid metabolism. Metabolomic and gene expression analyses of CFD-knockdown PH-Fibs revealed restored metabolic and inflammatory profiles, underscoring CFD's crucial role in these changes. This study emphasizes the crucial role of intracellular complement in PH pathogenesis, highlighting the potential for complement-targeted therapies in PH.

The Utility of Synovial Fluid Interleukin-10 in Diagnosing Chronic Periprosthetic Joint Infection: A Prospective Cohort Study

Background

Diagnosing chronic periprosthetic joint infection (PJI) is challenging. Synovial fluid interleukin-10 (SF IL-10), an anti-inflammatory cytokine produced by leukocytes, plays a pivotal role in inflammation and infection regulation. However, limited research has explored the diagnostic potential of SF IL-10 in chronic PJI patients.

Objective

The study aimed to investigate the relationship between SF IL-10 and incidence of chronic PIJ, and to evaluate its diagnostic reliability.

Design and Methods

We analyzed data from 137 patients who underwent revision surgery for aseptic loosening or chronic PJI between 2017 and 2019 in our hospital. PJI diagnoses followed the 2013 International Consensus Meeting criteria. We measured serum ESR, serum CRP, SF PMN%, SF WBC and SF IL-10 levels, using logistic regression and receiver operating characteristic (ROC) curves to evaluate associations and diagnostic accuracy.

Results

Demographic data showed no significant differences. However, SF IL-10 levels differed significantly between groups. Logistic regression indicated a strong association between SF IL-10 and chronic PJI (OR = 1.11, 95% CI 1.05~1.17, p < 0.001). At a cut-off of 10.305 pg/mL, SF IL-10 had an area under the ROC curve (AUC) of 0.891, with 92.16% sensitivity and 77.91% specificity. Adding SF IL-10 to traditional models improved risk prediction for chronic PJI (net reclassification improvement [NRI]: 0.167 [0.023 ~ 0.312]; integrated discrimination improvement [IDI]: 0.160 [0.096 ~ 0.224]).

Conclusion

Higher SF IL-10 levels were significantly associated with chronic PJI in revision surgery patients, and incorporating SF IL-10 into the traditional risk model enhanced its predictive value for chronic PJI in these patients.

METTL3/miR-192-5p/SCD1 Axis Regulates Lipid Metabolism to Affect T Cell Differentiation in Asthma

Background: This study aimed to explore the mechanisms underlying T-cell differentiation in asthma. Methods and Results: Flow cytometry was performed to detect Th cells. LC-MS/MS was performed to assess lipid metabolism. HE staining was performed to assess the pathological changes of the lung tissues. ELISA was performed to detect cytokine levels. The results of quantitative real-time polymerase chain reaction (qRT-PCR) and western blot showed that miR-192-5p expression was decreased, while SCD1 expression was increased in CD4+T cells isolated from the peripheral blood of children with asthma. The dual luciferase reporter assay determined the direct interaction between miR-192-5p and SCD1. MiR-192-5p inhibitor reduced ASCL3 and PPARα, increased FASN and SREBP1c mRNA expression and protein levels in mouse spleen CD4+T cells, and elevated Th2 and Th17 cells, but these effects were reversed by the SCD1 inhibitor. Oleic acid (OA) reduced Th1 cells and increased Th2 and Th17 cells in mouse spleen CD4+T cells treated with an SCD1 inhibitor. Additionally, pri-miR-192-5p expression was increased in CD4+T cells isolated from the peripheral blood of asthmatic children, and the deletion of METTL3 upregulated pri-miR-192-5p expression in an m6A-dependent manner. MiR-192-5p mimic and inhibitor both reversed miR-192-5p and SCD1 expression affected by overexpression or deletion of METTL3, both in vivo and in vitro. Furthermore, METTL3 overexpression attenuated lung inflammation, elevated Th1 cells, and reduced Th2 and Th17 cells in CD4+T cells isolated from the peripheral blood of asthmatic mice. These effects were reversed by the miR-192-5p inhibitor. Conclusion: These results suggest that METTL3/miR-192-5p/SCD1 axis regulates lipid metabolism and affects T cell differentiation, thus affecting asthma progression. This study may provide novel insights into the pathogenesis of asthma and a new treatment strategy.

Stearoyl-CoA desaturase in CD4+ T cells suppresses tumor growth through activation of the CXCR3/CXCL11 axis in CD8+ T cells

BACKGROUND

Within the tumor microenvironment, altered lipid metabolism promotes cancer cell malignancy by activating oncogenic cascades; however, impact of lipid metabolism in CD4+ tumor-infiltrating lymphocytes (TILs) remains poorly understood. Here, we elucidated that role of stearoyl-CoA desaturase (SCD) increased by treatment with cancer-associated fibroblast (CAF) supernatant in CD4+ T cells on their subset differentiation and activity of CD8+ T cells.

RESULTS

In our study, we observed that CD4+ TILs had higher lipid droplet content than CD4+ splenic T cells. In tumor tissue, CAF-derived supernatant provided fatty acids to CD4+ TILs, which increased the expression of SCD and oleic acid (OA) content. Increased SCD expression by OA treatment enhanced the levels of Th1 cell markers TBX21, interleukin-2, and interferon-γ. However, SCD inhibition upregulated the expression of regulatory T (Treg) cell markers, FOXP3 and transforming growth factor-β. Comparative fatty acid analysis of genetically engineered Jurkat cells revealed that OA level was significantly higher in SCD-overexpressing cells. Overexpression of SCD increased expression of Th1 cell markers, while treatment with OA enhanced the transcriptional level of TBX21 in Jurkat cells. In contrast, palmitic acid which is higher in SCD-KO cells than other subclones enhanced the expression of Treg cell markers through upregulation of mitochondrial superoxide. Furthermore, SCD increased the secretion of the C-X-C motif chemokine ligand 11 (CXCL11) from CD4+ T cells. The binding of CXCL11 to CXCR3 on CD8+ T cells augmented their cytotoxic activity. In a mouse tumor model, the suppressive effect of CD8+ T cells on tumor growth was dependent on CXCR3 expression.

CONCLUSION

These findings illustrate that SCD not only orchestrates the differentiation of T helper cells, but also promotes the antitumor activity of CD8+ T cells, suggesting its function in adverse tumor microenvironments.

Macrophages and T cells in metabolic disorder-associated cancers

Cancer and metabolic disorders have emerged as major global health challenges, reaching epidemic levels in recent decades. Often viewed as separate issues, metabolic disorders are shown by mounting evidence to heighten cancer risk and incidence. The intricacies underlying this connection are still being unraveled and encompass a complex interplay between metabolites, cancer cells and immune cells within the tumour microenvironment (TME). Here, we outline the interplay between metabolic and immune cell dysfunction in the context of three highly prevalent metabolic disorders, namely obesity; two associated liver diseases, metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH); and type 2 diabetes. We focus primarily on macrophages and T cells, the critical roles of which in dictating inflammatory response and immune surveillance in metabolic disorder-associated cancers are widely reported. Moreover, considering the ever-increasing number of patients prescribed with metabolism disorder-altering drugs and diets in recent years, we discuss how these therapies modulate systemic and local immune phenotypes, consequently impacting cancer malignancy. Collectively, unraveling the determinants of metabolic disorder-associated immune landscape and their role in fuelling cancer malignancy will provide a framework essential to therapeutically address these highly prevalent diseases.

Possible effects of ancestry-related oxysterol-binding protein-like 10 genetic polymorphisms on dengue virus replication and anti-dengue immune response

Purpose

Oxysterol-binding protein-like 10 (OSBPL10) gene has been associated with reduced susceptibility to severe dengue in individuals of African descent. The aim of this study was to determine the possible effect of OSBPL10 on dengue virus (DENV) replication as well as the impact of African and European haplotypes of six OSBPL10 small nuclear polymorphisms (SNPs) on dengue multiplication and innate immune response.

Methods

We conducted gene knockdown experiments targeting OSBPL10 in THP-1 and Huh-7D12 cell lines, followed by a DENV-2 replication assay. Extracellular viral load was determined using qRT-PCR. To investigate the impact of SNPs haplotypes on viral replication and gene expression we cultured peripheral blood mononuclear cells (PBMC) from individuals with homozygous African and European haplotypes of OSBPL10 with DENV-2. Individual genotyping was performed using High Resolution Melt (HRM) analysis. The level of viral replication was assessed through plaque assay, while RT-PCR was employed to determine the expression levels of RXR-α, IFN-γ, IL-10 and IL-8 genes.

Results

In vitro OSBPL10 knockdown significantly reduced DENV-2 replication. Individuals carrying European haplotypes showed higher DENV titers along with elevated levels of RXR-α and IL-8 mRNA compared to those carrying African haplotypes, who exhibited lower viral loads alongside increased IFN-γ and IL-10 expression.

Conclusions

Our findings further explore the role of OSBPL10 in DENV multiplication, immune response to infection. The European haplotypes of OSBPL10 appear to increase DENV replication and promote RXR-α and IL-8 mRNA expression which correlates with the suppressive effect of these mediators on type I IFN, promoting viral replication and a deficient antiviral response. In contrast, the African haplotype showed a reduction in DENV replication and enhanced IFN-γ and IL-10 mRNA expression, which could be related to the better management of dengue infection and the low frequency of severe disease in this ethnic groupe.

AGFG1 increases cholesterol biosynthesis by disrupting intracellular cholesterol homeostasis to promote PDAC progression

PURPOSE

Cholesterol metabolism reprograming has been acknowledged as a novel feature of cancers. Pancreatic ductal adenocarcinoma (PDAC) is a cancer with a high demand of cholesterol for rapid growth. The underlying mechanism of how cholesterol metabolism homestasis are disturbed in PDAC is explored.

EXPERIMENTAL DESIGN

The relevance between PDAC and cholesterol was confirmed in TCGA database. The expression and clinical association were discovered in TCGA and GEO datasets. Knockdown and overexpression of AGFG1 was adopted to perform function studies. RNA sequencing, cholesterol detection, transmission electron microscope, co-immunoprecipitation, and immunofluorescence et al. were utilized to reveal the underlying mechanism.

RESULTS

AGFG1 was identified as one gene positively correlated with cholesterol metabolism in PDAC as revealed by bioinformatics analysis. AGFG1 expression was then found associated with poor prognosis in PDAC. AGFG1 knockdown led to decreased proliferation of tumor cells both in vitro and in vivo. By RNA sequencing, we found AGFG1 upregulated expression leads to enhanced intracellular cholesterol biosynthesis. AGFG1 knockdown suppressed cholesterol biosynthesis and an accumulation of cholesterol in the ER. Mechanistically, we confirmed that AGFG1 interacted with CAV1 to relocate cholesterol for the proceeding of cholesterol biosynthesis, therefore causing disorders in intracellular cholesterol metabolism.

CONCLUSIONS

Our study demonstrates the tumor-promoting role of AGFG1 by disturbing cholesterol metabolism homestasis in PDAC. Our study has present a new perspective on cancer therapeutic approach based on cholerstrol metabolism in PDAC.

Targeting dysregulated intracellular immunometabolism within synovial microenvironment in rheumatoid arthritis with natural products

Immunometabolism has been an emerging hotspot in the fields of tumors, obesity, and atherosclerosis in recent decades, yet few studies have investigated its connection with rheumatoid arthritis (RA). In principle, intracellular metabolic pathways upstream regulated by nutrients and growth factors control the effector functions of immune cells. Dynamic communication and hypermetabolic lesions of immune cells within the inflammatory synovial microenvironment contributes to the development and progression of RA. Hence, targeting metabolic pathways within immune subpopulations and pathological cells may represent novel therapeutic strategies for RA. Natural products constitute a great potential treasury for the research and development of novel drugs targeting RA. Here, we aimed to delineate an atlas of glycolysis, lipid metabolism, amino acid biosynthesis, and nucleotide metabolism in the synovial microenvironment of RA that affect the pathological processes of synovial cells. Meanwhile, therapeutic potentials and pharmacological mechanisms of natural products that are demonstrated to inhibit related key enzymes in the metabolic pathways or reverse the metabolic microenvironment and communication signals were discussed and highlighted.

Advance in Multi-omics Research Strategies on Cholesterol Metabolism in Psoriasis

The skin is a complex and dynamic organ where homeostasis is maintained through the intricate interplay between the immune system and metabolism, particularly cholesterol metabolism. Various factors such as cytokines, inflammatory mediators, cholesterol metabolites, and metabolic enzymes play crucial roles in facilitating these interactions. Dysregulation of this delicate balance contributes to the pathogenic pathways of inflammatory skin conditions, notably psoriasis. In this article, we provide an overview of omics biomarkers associated with psoriasis in relation to cholesterol metabolism. We explore multi-omics approaches that reveal the communication between immunometabolism and psoriatic inflammation. Additionally, we summarize the use of multi-omics strategies to uncover the complexities of multifactorial and heterogeneous inflammatory diseases. Finally, we highlight potential future perspectives related to targeted drug therapies and research areas that can advance precise medicine. This review aims to serve as a valuable resource for those investigating the role of cholesterol metabolism in psoriasis.

Interleukin 21 Drives a Hypermetabolic State and CD4+ T-Cell-Associated Pathogenicity in Chronic Intestinal Inflammation

BACKGROUND & AIMS

Incapacitated regulatory T cells (Tregs) contribute to immune-mediated diseases. Inflammatory Tregs are evident during human inflammatory bowel disease; however, mechanisms driving the development of these cells and their function are not well understood. Therefore, we investigated the role of cellular metabolism in Tregs relevant to gut homeostasis.

METHODS

Using human Tregs, we performed mitochondrial ultrastructural studies via electron microscopy and confocal imaging, biochemical and protein analyses using proximity ligation assay, immunoblotting, mass cytometry and fluorescence-activated cell sorting, metabolomics, gene expression analysis, and real-time metabolic profiling utilizing the Seahorse XF analyzer. We used a Crohn's disease single-cell RNA sequencing dataset to infer the therapeutic relevance of targeting metabolic pathways in inflammatory Tregs. We examined the superior functionality of genetically modified Tregs in CD4+ T-cell-induced murine colitis models.

RESULTS

Mitochondria-endoplasmic reticulum appositions, known to mediate pyruvate entry into mitochondria via voltage-dependent anion channel 1 (VDAC1), are abundant in Tregs. VDAC1 inhibition perturbed pyruvate metabolism, eliciting sensitization to other inflammatory signals reversible by membrane-permeable methyl pyruvate supplementation. Notably, interleukin (IL) 21 diminished mitochondria-endoplasmic reticulum appositions, resulting in enhanced enzymatic function of glycogen synthase kinase 3 β, a putative negative regulator of VDAC1, and a hypermetabolic state that amplified Treg inflammatory response. Methyl pyruvate and glycogen synthase kinase 3 β pharmacologic inhibitor (LY2090314) reversed IL21-induced metabolic rewiring and inflammatory state. Moreover, IL21-induced metabolic genes in Tregs in vitro were enriched in human Crohn's disease intestinal Tregs. Adoptively transferred Il21r-/- Tregs efficiently rescued murine colitis in contrast to wild-type Tregs.

CONCLUSIONS

IL21 triggers metabolic dysfunction associated with Treg inflammatory response. Inhibiting IL21-induced metabolism in Tregs may mitigate CD4+ T-cell-driven chronic intestinal inflammation.

TNF-α signals through ITK-Akt-mTOR to drive CD4+ T cell metabolic reprogramming, which is dysregulated in rheumatoid arthritis

Upon activation, T cells undergo metabolic reprogramming to meet the bioenergetic demands of clonal expansion and effector function. Because dysregulated T cell cytokine production and metabolic phenotypes coexist in chronic inflammatory disease, including rheumatoid arthritis (RA), we investigated whether inflammatory cytokines released by differentiating T cells amplified their metabolic changes. We found that tumor necrosis factor-α (TNF-α) released by human naïve CD4+ T cells upon activation stimulated the expression of a metabolic transcriptome and increased glycolysis, amino acid uptake, mitochondrial oxidation of glutamine, and mitochondrial biogenesis. The effects of TNF-α were mediated by activation of Akt-mTOR signaling by the kinase ITK and did not require the NF-κB pathway. TNF-α stimulated the differentiation of naïve cells into proinflammatory T helper 1 (TH1) and TH17 cells, but not that of regulatory T cells. CD4+ T cells from patients with RA showed increased TNF-α production and consequent Akt phosphorylation upon activation. These cells also exhibited increased mitochondrial mass, particularly within proinflammatory T cell subsets implicated in disease. Together, these findings suggest that T cell-derived TNF-α drives their metabolic reprogramming by promoting signaling through ITK, Akt, and mTOR, which is dysregulated in autoinflammatory disease.

Identification of a lipid homeostasis-related gene signature for predicting prognosis, immunity, and chemotherapeutic effect in patients with gastric cancer

Gastric cancer (GC) is one of the most common and deadliest cancers worldwide. Lipid homeostasis is essential for tumour development because lipid metabolism is one of the most important metabolic reprogramming pathways within tumours. Elucidating the mechanism of lipid homeostasis in GC might significantly improve treatment strategies and patient prognosis. GSE62254 was applied to construct a lipid homeostasis-related gene signature score (HGSscore) by multiple bioinformatic algorithms including weighted gene coexpression network analysis (WGCNA) and LASSO-Cox regression. A nomogram based on HGSscore and relevant clinical characteristics was constructed to predict the survival of patients with GC. TIMER and xCell were used to evaluate immune and stromal cell infiltration in the tumour microenvironment. Correlations between lipid homeostasis-related genes and chemotherapeutic efficacy were analysed in GSCAlite. RT‒qPCR and cell viability assays were applied to verify the findings in this study. HGSscore was constructed based on eighteen lipid homeostasis-related genes that were selected by WGCNA and LASSO-Cox regression. HGSscore was strongly associated with advanced TNM stage and showed satisfactory value in predicting GC prognosis in three independent cohorts. Furthermore, we found that HGSscore was associated with the tumour mutation burden (TMB) and immune/stromal cell infiltration, which are related to GC prognosis, indicating that lipid homeostasis impacts the formation of the tumour microenvironment (TME). With respect to the GSCAlite platform, PLOD2 and TGFB2 were shown to be positively related to chemotherapeutic resistance, while SLC10A7 was a favourable factor for chemotherapy efficacy. Cell viability assays showed that disrupted lipid homeostasis could attenuate GC cell viability. Moreover, RT‒qPCR revealed that lipid homeostasis could influence expression of specific genes. We identified a lipid homeostasis-related gene signature that correlated with survival, clinical characteristics, the TME, and chemotherapeutic efficacy in GC patients. This research provides a new perspective for improving prognosis and guiding individualized chemotherapy for patients with GC.

25-Hydroxycholesterol in health and diseases

Cholesterol is an essential structural component of all membranes of mammalian cells where it plays a fundamental role not only in cellular architecture, but also, for example, in signaling pathway transduction, endocytosis process, receptor functioning and recycling, or cytoskeleton remodeling. Consequently, intracellular cholesterol concentrations are tightly regulated by complex processes, including cholesterol synthesis, uptake from circulating lipoproteins, lipid transfer to these lipoproteins, esterification, and metabolization into oxysterols that are intermediates for bile acids. Oxysterols have been considered for long time as sterol waste products, but a large body of evidence has clearly demonstrated that they play key roles in central nervous system functioning, immune cell response, cell death, or migration and are involved in age-related diseases, cancers, autoimmunity, or neurological disorders. Among all the existing oxysterols, this review summarizes basic as well as recent knowledge on 25-hydroxycholesterol which is mainly produced during inflammatory or infectious situations and that in turn contributes to immune response, central nervous system disorders, atherosclerosis, macular degeneration, or cancer development. Effects of its metabolite 7α,25-dihydroxycholesterol are also presented and discussed.

Association Between Statin Use and Dementia, and Related Mechanisms: A Bibliometric Analysis from 2007 to 2023

Background

Emerging evidence suggests the potential of hydroxymethylglutaryl-coenzyme A (HMG-CoA, statins) as a therapeutic option for dementia.

Objective

The primary objective of this study is to assess the current state of research on statins use in dementia, with a focus on identifying pivotal questions within the field.

Methods

A systemic search for publications on statin use in dementia between 2007 and 2023 was conducted, utilizing the Web of Science Core Collection. The scientific output was analyzed from various perspectives through VOSviewer, CiteSpace, and the bibliometrics website (https://bibliometric.com/).

Results

560 articles authored by 2,977 individuals and 999 institutions across 58 countries were included, which were published in 295 periodicals and cited 21,176 references from 16,424 authors. The annual publication output remained steady, while the number of citations increased consistently. The U.S. and Mayo Clinic emerged as the most significant country and institution, respectively. B. McGuinness and D.L. Sparks were the most eminent authors. Journal of Alzheimer's Disease was the most influential journal. Three sets of keywords and the top 10 references were identified, suggesting pivotal questions within the field.

Conclusions

While statins show promising potential as a treatment option for dementia, their use remains uncertain due to the reported short-term cognitive impairment events and questionable long-term protective effects against dementia. The pivotal question is to ascertain the association between statins and cognition. The mechanisms underlying the effects of statins on cognition are multifaceted. This study provides insights into the current status within the field of statin use in dementia.

Complement, complosome, and complotype: A perspective

Recent rapid progress in key technological advances, including the broader accessibility of single-cell "omic" approaches, have allowed immunologists to gain important novel insights into the contributions of individual immune cells in protective immunity and immunopathologies. These insights also taught us that there is still much to uncover about the (cellular) networks underlying immune responses. For example, in the last decade, studies on a key component of innate immunity, the complement system, have defined intracellularly active complement (the complosome) as a key orchestrator of normal cell physiology. This added an unexpected facet to the biology of complement, which was long considered fully explored. Here, we will summarize succinctly the known activation modes and functions of the complosome and provide a perspective on the origins of intracellular complement. We will also make a case for extending assessments of the complotype, the individual inherited landscape of common variants in complement genes, to the complosome, and for reassessing patients with known serum complement deficiencies for complosome perturbations. Finally, we will discuss where we see current opportunities and hurdles for dissecting the compartmentalization of complement activities toward a better understanding of their contributions to cellular function in health and disease.

Blimp-1 and c-Maf regulate Il10 and negatively regulate common and unique proinflammatory gene networks in IL-12 plus IL-27-driven T helper-1 cells

Background

CD4 + Th1 cells producing IFN-γ are required to eradicate intracellular pathogens, however if uncontrolled these cells can cause immunopathology. The cytokine IL-10 is produced by multiple immune cells including Th1 cells during infection and regulates the immune response to minimise collateral host damage. In this study we aimed to elucidate the transcriptional network of genes controlling the expression of Il10 and proinflammatory cytokines, including Ifng in Th1 cells differentiated from mouse naive CD4 + T cells.

Methods

We applied computational analysis of gene regulation derived from temporal profiling of gene expression clusters obtained from bulk RNA sequencing (RNA-seq) of flow cytometry sorted naïve CD4 + T cells from mouse spleens differentiated in vitro into Th1 effector cells with IL-12 and IL-27 to produce Ifng and Il10, compared to IL-27 alone which express Il10 only , or IL-12 alone which express Ifng and no Il10, or medium control driven-CD4 + T cells which do not express effector cytokines . Data were integrated with analysis of active genomic regions from these T cells using an assay for transposase-accessible chromatin with sequencing (ATAC)-seq, integrated with literature derived-Chromatin-immunoprecipitation (ChIP)-seq data and the RNA-seq data, to elucidate the transcriptional network of genes controlling expression of Il10 and pro-inflammatory effector genes in Th1 cells. The co-dominant role for the transcription factors, Prdm1 (encoding Blimp-1) and Maf (encoding c-Maf) , in cytokine gene regulation in Th1 cells, was confirmed using T cells obtained from mice with T-cell specific deletion of these transcription factors.

Results

We show that the transcription factors Blimp-1 and c-Maf each have unique and common effects on cytokine gene regulation and not only co-operate to induce Il10 gene expression in IL-12 plus IL-27 differentiated mouse Th1 cells, but additionally directly negatively regulate key proinflammatory cytokines including Ifng, thus providing mechanisms for reinforcement of regulated Th1 cell responses.

Conclusions

These data show that Blimp-1 and c-Maf positively and negatively regulate a network of both unique and common anti-inflammatory and pro-inflammatory genes to reinforce a Th1 response in mice that will eradicate pathogens with minimum immunopathology.

Maladaptive T-Cell Metabolic Fitness in Autoimmune Diseases

Immune surveillance and adaptive immune responses, involving continuously circulating and tissue-resident T-lymphocytes, provide host defense against infectious agents and possible malignant transformation while avoiding autoimmune tissue damage. Activation, migration, and deployment of T-cells to affected tissue sites are crucial for mounting an adaptive immune response. An effective adaptive immune defense depends on the ability of T-cells to dynamically reprogram their metabolic requirements in response to environmental cues. Inability of the T-cells to adapt to specific metabolic demands may skew cells to become either hyporesponsive (creating immunocompromised conditions) or hyperactive (causing autoimmune tissue destruction). Here, we review maladaptive T-cell metabolic fitness that can cause autoimmune diseases and discuss how T-cell metabolic programs can potentially be modulated to achieve therapeutic benefits.

Loss of CD4+ T cell-intrinsic arginase 1 accelerates Th1 response kinetics and reduces lung pathology during influenza infection

Arginase 1 (Arg1), the enzyme catalyzing the conversion of arginine to ornithine, is a hallmark of IL-10-producing immunoregulatory M2 macrophages. However, its expression in T cells is disputed. Here, we demonstrate that induction of Arg1 expression is a key feature of lung CD4+ T cells during mouse in vivo influenza infection. Conditional ablation of Arg1 in CD4+ T cells accelerated both virus-specific T helper 1 (Th1) effector responses and its resolution, resulting in efficient viral clearance and reduced lung pathology. Using unbiased transcriptomics and metabolomics, we found that Arg1-deficiency was distinct from Arg2-deficiency and caused altered glutamine metabolism. Rebalancing this perturbed glutamine flux normalized the cellular Th1 response. CD4+ T cells from rare ARG1-deficient patients or CRISPR-Cas9-mediated ARG1-deletion in healthy donor cells phenocopied the murine cellular phenotype. Collectively, CD4+ T cell-intrinsic Arg1 functions as an unexpected rheostat regulating the kinetics of the mammalian Th1 lifecycle with implications for Th1-associated tissue pathologies.

Interleukin-21 Drives a Hypermetabolic State and CD4+ T Cell-associated Pathogenicity in Chronic Intestinal Inflammation

BACKGROUND & AIMS

Incapacitated regulatory T cells (Tregs) contribute to immune-mediated diseases. Inflammatory Tregs are evident during human inflammatory bowel disease (IBD); however, mechanisms driving the development of these cells and their function are not well understood. Therefore, we investigated the role of cellular metabolism in Tregs relevant to gut homeostasis.

METHODS

Using human Tregs, we performed mitochondrial ultrastructural studies via electron microscopy and confocal imaging, biochemical and protein analyses using proximity ligation assay, immunoblotting, mass cytometry and fluorescence-activated cell sorting, metabolomics, gene expression analysis, and real-time metabolic profiling utilizing Seahorse XF analyzer. We utilized Crohn's disease single-cell RNA sequencing dataset to infer therapeutic relevance of targeting metabolic pathways in inflammatory Tregs. We examined the superior functionality of genetically-modified Tregs in CD4+ T cell-induced murine colitis models.

RESULTS

Mitochondria-endoplasmic reticulum (ER) appositions, known to mediate pyruvate entry into mitochondria via VDAC1, are abundant in Tregs. VDAC1 inhibition perturbed pyruvate metabolism, eliciting sensitization to other inflammatory signals reversible by membrane-permeable methyl pyruvate (MePyr) supplementation. Notably, IL-21 diminished mitochondria-ER appositions, resulting in enhanced enzymatic function of glycogen synthase kinase 3 β (GSK3β), a putative negative regulator of VDAC1, and a hypermetabolic state that amplified Treg inflammatory response. MePyr and GSK3β pharmacologic inhibitor (LY2090314) reversed IL-21-induced metabolic rewiring and inflammatory state. Moreover, IL-21-induced metabolic genes in Tregs in vitro were enriched in human Crohn's disease intestinal Tregs. Adoptively transferred Il21r-/- Tregs efficiently rescued murine colitis in contrast to wild-type Tregs.

CONCLUSIONS

IL-21 triggers metabolic dysfunction associated with Treg inflammatory response. Inhibiting IL-21-induced metabolism in Tregs may mitigate CD4+ T cell-driven chronic intestinal inflammation.

Complosome - the intracellular complement system

The complement system is a recognized pillar of host defence against infection and noxious self-derived antigens. Complement is traditionally known as a serum-effective system, whereby the liver expresses and secretes most complement components, which participate in the detection of bloodborne pathogens and drive an inflammatory reaction to safely remove the microbial or antigenic threat. However, perturbations in normal complement function can cause severe disease and, for reasons that are currently not fully understood, the kidney is particularly vulnerable to dysregulated complement activity. Novel insights into complement biology have identified cell-autonomous and intracellularly active complement - the complosome - as an unexpected central orchestrator of normal cell physiology. For example, the complosome controls mitochondrial activity, glycolysis, oxidative phosphorylation, cell survival and gene regulation in innate and adaptive immune cells, and in non-immune cells, such as fibroblasts and endothelial and epithelial cells. These unanticipated complosome contributions to basic cell physiological pathways make it a novel and central player in the control of cell homeostasis and effector responses. This discovery, together with the realization that an increasing number of human diseases involve complement perturbations, has renewed interest in the complement system and its therapeutic targeting. Here, we summarize the current knowledge about the complosome across healthy cells and tissues, highlight contributions from dysregulated complosome activities to human disease and discuss potential therapeutic implications.

Effects of Plasma-Derived Exosomal miRNA-19b-3p on Treg/T Helper 17 Cell Imbalance in Behçet's Uveitis

Purpose

To explore the potential role of plasma-derived exosomal microRNAs (miRNAs) in the development of regulatory T cell (Treg)/T helper 17 (Th17) cell imbalances in Behçet's uveitis (BU).

Methods

The exosome treatment was conducted to evaluate the effects of plasma exosomes from patients with active BU and healthy controls on the Treg/Th17 cell balance. miRNA sequencing analysis of plasma exosomes was conducted to identify differentially expressed miRNAs between patients with active BU and healthy controls. miRTarBase analysis and dual-luciferase reporter assays were conducted to identify the target genes of miR-19b-3p. CD4+T cells were transfected with miR-19b-3p mimic or inhibitor to evaluate its regulation of the Treg/Th17 cell balance. The Treg/Th17 cell balance in CD4+T cells was evaluated by flow cytometry and enzyme-linked immunosorbent assay.

Results

Exosomes from patients with active BU promoted Th17 cell differentiation and inhibited Treg cell differentiation. MiRNA sequencing analysis revealed 177 upregulated and 274 downregulated miRNAs in plasma exosomes of patients with active BU. Among them, miR-19b-3p was significantly elevated, and its target genes were identified as being involved in T-cell differentiation. miR-19b-3p overexpression downregulated CD46 expression and the Treg/Th17 cell ratio in CD4+T cells from healthy controls, whereas miR-19b-3p inhibition reversed these regulatory effects and restored the Treg/Th17 cell balance of CD4+T cells from patients with active BU.

Conclusions

Plasma-derived exosomes from patients with active BU showed a markedly differential miRNA expression in comparison to healthy controls. Highly expressed miRNA-19b-3p could induce a Treg/Th17 cell imbalance, probably by downregulating CD46 expression.

Dose-dependent effects of simvastatin, atorvastatin and rosuvastatin on apoptosis and inflammation pathways on cancerous lung cells

The aim of study was to investigate the anti-proliferative and inflammatory effects of atorvastatin, rosuvastatin, and simvastatin in lung cancer. The effects of statins were investigated in Vero, BEAS-2B, and A549 cell lines. In addition to expressions of BAX, BCL-2, TNFα, IL-10, IL-6, protein levels of TNFα, IL-10, IL-6 were determined. Cell viability and MDA were also measured. While the cell numbers in groups with low doses of statins were found to be approximately 1x106/mL, proliferation was inhibited at higher rates containing high doses. Simvastatin, rosuvastatin, and high dose atorvastatin upregulated the BAX, while high dose of atorvastatin and both doses of rosuvastatin caused downregulation in BCL-2. All statin groups had higher MDA. Simvastatin and high dose rosuvastatin upregulated TNFα. While low dose simvastatin and atorvastatin and high dose atorvastatin and rosuvastatin upregulated IL-10, IL-6 was upregulated with a low dose of rosuvastatin. TNFα was higher in simvastatin and rosuvastatin groups. IL-10 was highest in rosuvastatin groups. Atorvastatin groups had lower IL-6. Although cell numbers have been reduced by all statins, rosuvastatin is more effective on studied genes.

Phenotypic screening platform identifies statins as enhancers of immune cell-induced cancer cell death

BACKGROUND

High-throughput screening (HTS) of small molecule drug libraries has greatly facilitated the discovery of new cancer drugs. However, most phenotypic screening platforms used in the field of oncology are based solely on cancer cell populations and do not allow for the identification of immunomodulatory agents.

METHODS

We developed a phenotypic screening platform based on a miniaturized co-culture system with human colorectal cancer- and immune cells, providing a model that recapitulates part of the tumor immune microenvironment (TIME) complexity while simultaneously being compatible with a simple image-based readout. Using this platform, we screened 1,280 small molecule drugs, all approved by the Food and Drug Administration (FDA), and identified statins as enhancers of immune cell-induced cancer cell death.

RESULTS

The lipophilic statin pitavastatin had the most potent anti-cancer effect. Further analysis demonstrated that pitavastatin treatment induced a pro-inflammatory cytokine profile as well as an overall pro-inflammatory gene expression profile in our tumor-immune model.

CONCLUSION

Our study provides an in vitro phenotypic screening approach for the identification of immunomodulatory agents and thus addresses a critical gap in the field of immuno-oncology. Our pilot screen identified statins, a drug family gaining increasing interest as repurposing candidates for cancer treatment, as enhancers of immune cell-induced cancer cell death. We speculate that the clinical benefits described for cancer patients receiving statins are not simply caused by a direct effect on the cancer cells but rather are dependent on the combined effect exerted on both cancer and immune cells.

Low-density lipoprotein balances T cell metabolism and enhances response to anti-PD-1 blockade in a HCT116 spheroid model

Introduction

The discovery of immune checkpoints and the development of their specific inhibitors was acclaimed as a major breakthrough in cancer therapy. However, only a limited patient cohort shows sufficient response to therapy. Hence, there is a need for identifying new checkpoints and predictive biomarkers with the objective of overcoming immune escape and resistance to treatment. Having been associated with both, treatment response and failure, LDL seems to be a double-edged sword in anti-PD1 immunotherapy. Being embedded into complex metabolic conditions, the impact of LDL on distinct immune cells has not been sufficiently addressed. Revealing the effects of LDL on T cell performance in tumor immunity may enable individual treatment adjustments in order to enhance the response to routinely administered immunotherapies in different patient populations. The object of this work was to investigate the effect of LDL on T cell activation and tumor immunity in-vitro.

Methods

Experiments were performed with different LDL dosages (LDL^low = 50 μg/ml and LDL^high = 200 μg/ml) referring to medium control. T cell phenotype, cytokines and metabolism were analyzed. The functional relevance of our findings was studied in a HCT116 spheroid model in the context of anti-PD-1 blockade.

Results

The key points of our findings showed that LDL^high skewed the CD4⁺ T cell subset into a central memory-like phenotype, enhanced the expression of the co-stimulatory marker CD154 (CD40L) and significantly reduced secretion of IL-10. The exhaustion markers PD-1 and LAG-3 were downregulated on both T cell subsets and phenotypical changes were associated with a balanced T cell metabolism, in particular with a significant decrease of reactive oxygen species (ROS). T cell transfer into a HCT116 spheroid model resulted in a significant reduction of the spheroid viability in presence of an anti-PD-1 antibody combined with LDL^high.

Discussion

Further research needs to be conducted to fully understand the impact of LDL on T cells in tumor immunity and moreover, to also unravel LDL effects on other lymphocytes and myeloid cells for improving anti-PD-1 immunotherapy. The reason for improved response might be a resilient, less exhausted phenotype with balanced ROS levels.

B Cells at the Cross-Roads of Autoimmune Diseases and Auto-Inflammatory Syndromes

Whereas autoimmune diseases are mediated primarily by T and B cells, auto-inflammatory syndromes (AIFS) involve natural killer cells, macrophages, mast cells, dendritic cells, different granulocyte subsets and complement components. In contrast to autoimmune diseases, the immune response of patients with AIFS is not associated with a breakdown of immune tolerance to self-antigens. Focusing on B lymphocyte subsets, this article offers a fresh perspective on the multiple cross-talks between both branches of innate and adaptive immunity in mounting coordinated signals that lead to AIFS. By virtue of their potential to play a role in adaptive immunity and to exert innate-like functions, B cells can be involved in both promoting inflammation and mitigating auto-inflammation in disorders that include mevalonate kinase deficiency syndrome, Kawasaki syndrome, inflammatory bone disorders, Schnitzler syndrome, Neuro-Behçet's disease, and neuromyelitis optica spectrum disorder. Since there is a significant overlap between the pathogenic trajectories that culminate in autoimmune diseases, or AIFS, a more detailed understanding of their respective roles in the development of inflammation could lead to designing novel therapeutic avenues.

IL-10: A bridge between immune cells and metabolism during pregnancy

Energy metabolism plays a crucial role in the immune system. In addition to providing vital energy for cell growth, reproduction and other cell activities, the metabolism of nutrients such as glucose and lipids also have significant effects on cell function through metabolites, metabolic enzymes, and changing metabolic status. Interleukin-10 (IL-10), as a pleiotropic regulator, can be secreted by a diverse set of cells and can also participate in regulating the functions of various cells, thereby playing an essential role in the formation and maintenance of immune tolerance in pregnancy. Studies on the regulatory effects and mechanisms of IL-10 on immune cells are extensive; however, research from a metabolic perspective is relatively negligible. Here, we have discussed old and new data on the relationship between IL-10 and metabolism. The data show that alterations in cellular metabolism and specific metabolites regulate IL-10 production of immune cells. Moreover, IL-10 regulates immune cell phenotypes and functions by modulating oxidative phosphorylation and glycolysis. This review summarizes some earlier observations regarding IL-10 and its relationship with immune cells in pregnancy, and also presents recent research on the link between IL-10 and metabolism, highlighting the potential relationship between IL-10, immune cells, and energy metabolism during pregnancy.

Pathogenic role of 25-hydroxycholesterol in cancer development and progression

Cholesterol is an essential lipid that serves several important functions, including maintaining the homeostasis of cells, acting as a precursor to bile acid and steroid hormones and preserving the stability of membrane lipid rafts. 25-hydroxycholesterol (25-HC) is a cholesterol derivative that may be formed from cholesterol. 25-HC is a crucial component in various biological activities, including cholesterol metabolism. In recent years, growing evidence has shown that 25-HC performs a critical function in the etiology of cancer, infectious diseases and autoimmune disorders. This review will summarize the latest findings regarding 25-HC, including its biogenesis, immunomodulatory properties and role in innate/adaptive immunity, inflammation and the development of various types of cancer.

Synovial gene signatures associated with the development of rheumatoid arthritis in at risk individuals: A prospective study

OBJECTIVE

To identify molecular changes in synovium before arthritis development in individuals at risk of developing rheumatoid arthritis (RA).

MATERIALS AND METHODS

We included 67 IgM rheumatoid factor and/or anti-citrullinated protein antibody positive individuals with arthralgia but without arthritis. Synovial biopsies were collected after which individuals were prospectively followed for at least 2 years during which 17 developed arthritis. An exploratory genome-wide transcriptional profiling study was performed in 13 preselected individuals to identify transcripts associated with arthritis development (n = 6). Findings were validated using quantitative real-time PCR and immunohistochemistry in the total cohort.

RESULTS

Microarray-based survival analyses identified 5588 transcripts whose expression levels in synovium were significantly associated with arthritis development. Pathway analysis revealed that synovial tissue of at risk individuals who later developed arthritis display higher expression of genes involved in adaptive immune response-related pathways compared to at risk individuals who did not develop arthritis. Lower expression was observed for genes involved in extracellular matrix receptor interaction, Wnt-mediated signal transduction and lipid metabolism. Two-way hierarchical clustering analyses of a 27-gene signature separated the total at risk cohort into two groups, where pre-RA individuals preferred to cluster together. Immunohistochemistry studies revealed more podoplanin positive cells and lower lipid droplet staining in synovial tissue from pre-RA individuals.

CONCLUSION

Synovial alterations in adaptive immune response and lipid metabolism are associated with future development of arthritis. Since this data show synovial changes without overt cellular infiltration, these may be attributed to preclinical changes in resident synovial tissue cells such as fibroblasts, macrophages and tissue resident T cells.

Linking nutrient sensing, mitochondrial function, and PRR immune cell signaling in liver disease

Caloric overconsumption in vertebrates promotes adipose and liver fat accumulation while perturbing the gut microbiome. This triad triggers pattern recognition receptor (PRR)-mediated immune cell signaling and sterile inflammation. Moreover, immune system activation perpetuates metabolic consequences, including the progression of nonalcoholic fatty liver disease (NAFLD) to nonalcoholic hepatic steatohepatitis (NASH). Recent findings show that sensing of nutrient overabundance disrupts the activity and homeostasis of the central cellular energy-generating organelle, the mitochondrion. In parallel, whether caloric excess-initiated PRR signaling and mitochondrial perturbations are coordinated to amplify this inflammatory process in NASH progression remains in question. We hypothesize that altered mitochondrial function, classic PRR signaling, and complement activation in response to nutrient overload together play an integrated role across the immune cell landscape, leading to liver inflammation and NASH progression.

The bridge of the gut-joint axis: Gut microbial metabolites in rheumatoid arthritis

Rheumatoid arthritis (RA) is an autoimmune disease characterized by joint destruction, synovitis, and pannus formation. Gut microbiota dysbiosis may exert direct pathogenic effects on gut homeostasis. It may trigger the host's innate immune system and activate the "gut-joint axis", which exacerbates the RA. However, although the importance of the gut microbiota in the development and progression of RA is widely recognized, the mechanisms regulating the interactions between the gut microbiota and the host immune system remain incompletely defined. In this review, we discuss the role of gut microbiota-derived biological mediators, such as short-chain fatty acids, bile acids, and tryptophan metabolites, in maintaining intestinal barrier integrity, immune balance and bone destruction in RA patients as the bridge of the gut-joint axis.

Regulation of immune cell metabolism in health and disease: Special focus on T and B cell subsets

Metabolism is a dynamic process and keeps changing from time to time according to the demand of a particular cell to meet its bio-energetic requirement. Different immune cells rely on distinct metabolic programs which allow the cell to balance its requirements for energy, molecular biosynthesis, and effector activity. In the aspect of infection and cancer immunology, effector T and B cells get exhausted and help tumor cells to evade immunosurveillance. On the other hand, T cells become hyperresponsive in the scenario of autoimmune diseases. In this article, we have explored the uniqueness and distinct metabolic features of key CD4⁺ T and B helper cell subsets, CD4⁺ T, B regulatory cell subsets and CD8⁺ T cells regarding health and disease. Th1 cells rely on glycolysis and glutaminolysis; inhibition of these metabolic pathways promotes Th1 cells in Treg population. However, Th2 cells are also dependent on glycolysis but an abundance of lactate within TME shifts their metabolic dependency to fatty acid metabolism. Th17 cells depend on HIF-1α mediated glycolysis, ablation of HIF-1α reduces Th17 cells but enhance Treg population. In contrast to effector T cells which are largely dependent on glycolysis for their differentiation and function, Treg cells mainly rely on FAO for their function. Therefore, it is of utmost importance to understand the metabolic fates of immune cells and how it facilitates their differentiation and function for different disease models. Targeting metabolic pathways to restore the functionality of immune cells in diseased conditions can lead to potent therapeutic measures.

Dietary Cholesterol Causes Inflammatory Imbalance and Exacerbates Morbidity in Mice Infected with Influenza A Virus

Influenza is a common cause of pneumonia-induced hospitalization and death, but how host factors function to influence disease susceptibility or severity has not been fully elucidated. Cellular cholesterol levels may affect the pathogenesis of influenza infection, as cholesterol is crucial for viral entry and replication, as well as immune cell proliferation and function. However, there is still conflicting evidence on the extent to which dietary cholesterol influences cholesterol metabolism. In this study, we examined the effects of a high-cholesterol diet in modulating the immune response to influenza A virus (IAV) infection in mice. Mice were fed a standard or a high-cholesterol diet for 5 wk before inoculation with mouse-adapted human IAV (Puerto Rico/8/1934), and tissues were collected at days 0, 4, 8, and 16 postinfection. Cholesterol-fed mice exhibited dyslipidemia characterized by increased levels of total serum cholesterol prior to infection and decreased triglycerides postinfection. Cholesterol-fed mice also displayed increased morbidity compared with control-fed mice, which was neither a result of immunosuppression nor changes in viral load. Instead, transcriptomic analysis of the lungs revealed that dietary cholesterol caused upregulation of genes involved in viral-response pathways and leukocyte trafficking, which coincided with increased numbers of cytokine-producing CD4⁺ and CD8⁺ T cells and infiltrating dendritic cells. Morbidity as determined by percent weight loss was highly correlated with numbers of cytokine-producing CD4⁺ and CD8⁺ T cells as well as granulocytes. Taken together, dietary cholesterol promoted IAV morbidity via exaggerated cellular immune responses that were independent of viral load.

Cancer Metabolism: The Role of Immune Cells Epigenetic Alteration in Tumorigenesis, Progression, and Metastasis of Glioma

Glioma is a type of brain and spinal cord tumor that begins in glial cells that support the nervous system neurons functions. Age, radiation exposure, and family background of glioma constitute are risk factors of glioma initiation. Gliomas are categorized on a scale of four grades according to their growth rate. Grades one and two grow slowly, while grades three and four grow faster. Glioblastoma is a grade four gliomas and the deadliest due to its aggressive nature (accelerated proliferation, invasion, and migration). As such, multiple therapeutic approaches are required to improve treatment outcomes. Recently, studies have implicated the significant roles of immune cells in tumorigenesis and the progression of glioma. The energy demands of gliomas alter their microenvironment quality, thereby inducing heterogeneity and plasticity change of stromal and immune cells via the PI3K/AKT/mTOR pathway, which ultimately results in epigenetic modifications that facilitates tumor growth. PI3K is utilized by many intracellular signaling pathways ensuring the proper functioning of the cell. The activation of PI3K/AKT/mTOR regulates the plasma membrane activities, contributing to the phosphorylation reaction necessary for transcription factors activities and oncogenes hyperactivation. The pleiotropic nature of PI3K/AKT/mTOR makes its activity unpredictable during altered cellular functions. Modification of cancer cell microenvironment affects many cell types, including immune cells that are the frontline cells involved in inflammatory cascades caused by cancer cells via high cytokines synthesis. Typically, the evasion of immunosurveillance by gliomas and their resistance to treatment has been attributed to epigenetic reprogramming of immune cells in the tumor microenvironment, which results from cancer metabolism. Hence, it is speculative that impeding cancer metabolism and/or circumventing the epigenetic alteration of immune cell functions in the tumor microenvironment might enhance treatment outcomes. Herein, from an oncological and immunological perspective, this review discusses the underlying pathomechanism of cell-cell interactions enhancing glioma initiation and metabolism activation and tumor microenvironment changes that affect epigenetic modifications in immune cells. Finally, prospects for therapeutic intervention were highlighted.

Effects of Oxysterols on Immune Cells and Related Diseases

Oxysterols are the products of cholesterol oxidation. They have a wide range of effects on several cells, organs, and systems in the body. Oxysterols also have an influence on the physiology of the immune system, from immune cell maturation and migration to innate and humoral immune responses. In this regard, oxysterols have been involved in several diseases that have an immune component, from autoimmune and neurodegenerative diseases to inflammatory diseases, atherosclerosis, and cancer. Here, we review data on the participation of oxysterols, mainly 25-hydroxycholesterol and 7α,25-dihydroxycholesterol, in the immune system and related diseases. The effects of these oxysterols and main oxysterol receptors, LXR and EBI2, in cells of the immune system (B cells, T cells, macrophages, dendritic cells, oligodendrocytes, and astrocytes), and in immune-related diseases, such as neurodegenerative diseases, intestinal diseases, cancer, respiratory diseases, and atherosclerosis, are discussed.

25-hydroxycholesterol-induced cell death via activation of ROCK/LIMK/cofilin axis in colorectal cancer cell spheroids

25-Hydroxycholesterol (25OHC) induces anchorage-dependent programmed cell death, or anoikis, in colorectal cancer cells but the mechanism is not fully understood. Here, we found that 25OHC induced cofilin phosphorylation and promoted rearrangement of the actin cytoskeleton in spheroids of the colorectal cancer cell lines, DLD1 and HT29/WiDr. Cell death induced by 25OHC was inhibited by the actin polymerization inhibitor, cytochalasin D, and BMS-3, an inhibitor of LIMK, which phosphorylates and inactivates cofilin. In addition, we showed that cofilin phosphorylation induced by 25OHC was associated with caspase-3 activation, which can activate ROCK. Rho GTPase was directly activated by 25OHC. These results indicate that 25OHC affects actin dynamics through activation of the Rho/ROCK/LIMK/cofilin axis, eventuating in the cell death of colorectal cancer cell spheroids.

Susceptibility to disease (tropical theileriosis) is associated with differential expression of host genes that possess motifs recognised by a pathogen DNA binding protein

Background

Knowledge of factors that influence the outcome of infection are crucial for determining the risk of severe disease and requires the characterisation of pathogen-host interactions that have evolved to confer variable susceptibility to infection. Cattle infected by Theileria annulata show a wide range in disease severity. Native (Bos indicus) Sahiwal cattle are tolerant to infection, whereas exotic (Bos taurus) Holstein cattle are susceptible to acute disease.

Methodology/Principal findings

We used RNA-seq to assess whether Theileria infected cell lines from Sahiwal cattle display a different transcriptome profile compared to Holstein and screened for altered expression of parasite factors that could generate differences in host cell gene expression.

Significant differences (<0.1 FDR) in the expression level of a large number (2211) of bovine genes were identified, with enrichment of genes associated with Type I IFN, cholesterol biosynthesis, oncogenesis and parasite infection. A screen for parasite factors found limited evidence for differential expression. However, the number and location of DNA motifs bound by the TashAT2 factor (TA20095) were found to differ between the genomes of B. indicus vs. B. taurus, and divergent motif patterns were identified in infection-associated genes differentially expressed between Sahiwal and Holstein infected cells.

Conclusions/Significance

We conclude that divergent pathogen-host molecular interactions that influence chromatin architecture of the infected cell are a major determinant in the generation of gene expression differences linked to disease susceptibility.

A Notch/STAT3-driven Blimp-1/c-Maf-dependent molecular switch induces IL-10 expression in human CD4+ T cells and is defective in Crohn´s disease patients

Immunosuppressive Interleukin (IL)-10 production by pro-inflammatory CD4⁺ T cells is a central self-regulatory function to limit aberrant inflammation. Still, the molecular mediators controlling IL-10 expression in human CD4⁺ T cells are largely undefined. Here, we identify a Notch/STAT3 signaling-module as a universal molecular switch to induce IL-10 expression across human naïve and major effector CD4⁺ T cell subsets. IL-10 induction was transient, jointly controlled by the transcription factors Blimp-1/c-Maf and accompanied by upregulation of several co-inhibitory receptors, including LAG-3, CD49b, PD-1, TIM-3 and TIGIT. Consistent with a protective role of IL-10 in inflammatory bowel diseases (IBD), effector CD4⁺ T cells from Crohn's disease patients were defective in Notch/STAT3-induced IL-10 production and skewed towards an inflammatory Th1/17 cell phenotype. Collectively, our data identify a Notch/STAT3-Blimp-1/c-Maf axis as a common anti-inflammatory pathway in human CD4⁺ T cells, which is defective in IBD and thus may represent an attractive therapeutic target.

The cholesterol pathway: impact on immunity and cancer

Cholesterol is a multifaceted metabolite that is known to modulate processes in cancer, atherosclerosis, and autoimmunity. A common denominator between these diseases appears to be the immune system, in which many cholesterol-associated metabolites impact both adaptive and innate immunity. Many cancers display altered cholesterol metabolism, and recent studies demonstrate that manipulating systemic cholesterol metabolism may be useful in improving immunotherapy responses. However, cholesterol can have both proinflammatory and anti-inflammatory roles in mammals, acting via multiple immune cell types, and depending on context. Gaining mechanistic insights into various cholesterol-related metabolites can improve our understanding of their functions and extensive effects on the immune system, and ideally will inform the design of future therapeutic strategies against cancer and/or other pathologies.

Immunometabolism modulation, a new trick of edible and medicinal plants in cancer treatment

The edible and medicinal plants (EMPs) are becoming an abundant source for cancer prevention and treatment since the natural and healthy trend for modern human beings. Currently, there are more than one hundred species of EMPs widely used and listed by the national health commission of China, and most of them indicate immune or metabolic regulation potential in cancer treatment with numerous studies over the past two decades. In the present review, we focused on the metabolic influence in immunocytes and tumor microenvironment, including immune response, immunosuppressive factors and cancer cells, discussing the immunometabolic potential of EMPs in cancer treatment. There are more than five hundred references collected and analyzed through retrieving pharmacological studies deposited in PubMed by medical subject headings and the corresponding names derived from pharmacopoeia of China as a sole criterion. Finally, the immunometabolism modulation of EMPs was sketch out implying an immunometabolic control in cancer treatment.

Obesity-Specific Association of Statin Use and Reduced Risk of Recurrence of Early Stage NSCLC

Introduction

Statins, used for their lipid-lowering activity, have anti-inflammatory and anticancer properties as well. We evaluated this potential benefit of statin use in patients with NSCLC.

Methods

All 613 patients with pathologic stage 1 or 2 NSCLC who had lobectomy without neoadjuvant therapy at our institution during 2008 to 2015 were included. Association between presurgery statin use and overall survival and recurrence-free survival (RFS) was analyzed using Cox proportional hazards regression. Association of statin use with tumor transcriptome was evaluated in another 350 lung cancer cases.

Results

Univariable analyses did not reveal a statistically significant association of statin use with either overall survival or RFS, with hazard ratio equals to 1.19 and 0.70 (Wald p = 0.28 and 0.09), respectively. In subgroup analyses, significantly improved RFS was found in statin users, but only in overweight/obese patients (body mass index [BMI] > 25; n = 422), with univariable and multivariable hazard ratio of 0.49 and 0.46 (p = 0.005 and 0.002), respectively, but not in patients with BMI less than or equal to 25 (n = 191; univariable p = 0.21). Transcriptomes of tumor statin users had high expression of tumoricidal genes such as granzyme A and interferon-γ compared with those of nonusers among high- but not low-BMI patients with lung cancer.

Conclusions

Our study suggests that statins may improve the outcome of early stage NSCLC but only in overweight or obese patients. This benefit may stem from a favorable reprogramming of the antitumor immune response that statins perpetrate specifically in the obese.

Association between cardiometabolic risk factors and COVID-19 susceptibility, severity and mortality: a review

The novel coronavirus, which began spreading from China Wuhan and gradually spreaded to most countries, led to the announcement by the World Health Organization on March 11, 2020, as a new pandemic. The most important point presented by the World Health Organization about this disease is to better understand the risk factors that exacerbate the course of the disease and worsen its prognosis. Due to the high majority of cardio metabolic risk factors like obesity, hypertension, diabetes, and dyslipidemia among the population over 60 years old and higher, these cardio metabolic risk factors along with the age of these people could worsen the prognosis of the coronavirus disease of 2019 (COVID-19) and its mortality. In this study, we aimed to review the articles from the beginning of the pandemic on the impression of cardio metabolic risk factors on COVID-19 and the effectiveness of COVID-19 on how to manage these diseases. All the factors studied in this article, including hypertension, diabetes mellitus, dyslipidemia, and obesity exacerbate the course of Covid-19 disease by different mechanisms, and the inflammatory process caused by coronavirus can also create a vicious cycle in controlling these diseases for patients.

Endosomal Cholesterol in Viral Infections - A Common Denominator?

Cholesterol has gained tremendous attention as an essential lipid in the life cycle of virtually all viruses. These seem to have developed manifold strategies to modulate the cholesterol metabolism to the side of lipid uptake and de novo synthesis. In turn, affecting the cholesterol homeostasis has emerged as novel broad-spectrum antiviral strategy. On the other hand, the innate immune system is similarly regulated by the lipid and stimulated by its derivatives. This certainly requires attention in the design of antiviral strategies aiming to decrease cellular cholesterol, as evidence accumulates that withdrawal of cholesterol hampers innate immunity. Secondly, there are exceptions to the rule of the abovementioned virus-induced metabolic shift toward cholesterol anabolism. It therefore is of interest to dissect underlying regulatory mechanisms, which we aimed for in this minireview. We further collected evidence for intracellular cholesterol concentrations being less important in viral life cycles as compared to the spatial distribution of the lipid. Various routes of cholesterol trafficking were found to be hijacked in viral infections with respect to organelle-endosome contact sites mediating cholesterol shuttling. Thus, re-distribution of cellular cholesterol in the context of viral infections requires more attention in ongoing research. As a final aim, a pan-antiviral treatment could be found just within the transport and re-adjustment of local cholesterol concentrations. Thus, we aimed to emphasize the importance of the regulatory roles the endosomal system fulfils herein and hope to stimulate research in this field.

The Many Roles of Cholesterol in Sepsis: A Review

RATIONALE

The biological functions of cholesterol are diverse, ranging from cell membrane integrity and signalling, immunity, to the synthesis of steroid and sex hormones, Vitamin D, bile acids and oxysterols. Multiple studies have demonstrated hypocholesterolemia in sepsis, the degree of which is an excellent prognosticator of poor outcomes. However, the clinical significance of hypocholesterolemia has been largely unrecognized.

OBJECTIVES/METHODS

We undertook a detailed review of the biological roles of cholesterol, the impact of sepsis, its reliability as a prognosticator in sepsis, and the potential utility of cholesterol as a treatment.

MEASUREMENTS AND MAIN RESULTS

Sepsis affects cholesterol synthesis, transport and metabolism. This likely impacts upon its biological functions including immunity, hormone and vitamin production, and cell membrane receptor sensitivity. Early preclinical studies show promise for cholesterol as a pleiotropic therapeutic agent.

CONCLUSIONS

Hypocholesterolemia is a frequent condition in sepsis and an important early prognosticator. Low plasma levels are associated with wider changes in cholesterol metabolism and its functional roles, and these appear to play a significant role in sepsis pathophysiology. The therapeutic impact of cholesterol elevation warrants further investigation.

Metabolomics Analysis of Splenic CD19+ B Cells in Mice Chronically Infected With Echinococcus granulosus sensu lato Protoscoleces

Background: The larval stages of Echinococcus granulosus sensu lato (E. granulosus s.l) infection can alter B cell function and affect host anti-infective immunity, but the underlying mechanism remains unclear. The newly emerging immunometabolism highlights that several metabolites are key factors in determining the fate of immune cells, which provides a new insight for exploring how larval E. granulosus s.l. infection remodels B cell function. This study investigated the metabolomic profiles of B cells in mice infected with E. granulosus s.l. protoscoleces (PSC).

Results:Total CD19⁺ B cells, purified from the spleen of infected mice, showed significantly increased production of IL-6, TNF-α, and IL-10 after exposure to LPS in vitro. Moreover, the mRNA expression of metabolism related enzymes in B cells was remarkably disordered post infection. In addition, differential metabolites were identified in B cells after infection. There were 340 differential metabolites (83 upregulated and 257 downregulated metabolites) identified in the positive ion model, and 216 differential metabolites (97 upregulated and 119 downregulated metabolites) identified in the negative ion mode. Among these, 64 differential metabolites were annotated and involved in 68 metabolic pathways, including thyroid hormone synthesis, the metabolic processes of glutathione, fructose, mannose, and glycerophospholipid. Furthermore, several differential metabolites such as glutathione, taurine, and inosine were validated to regulate the cytokine production in LPS stimulated B cells.

Conclusion:Infection with the larval E. granulosus s.l. causes metabolic reprogramming in the intrinsic B cells of mice, which provides the first evidence for understanding the role and mechanism of B cells in parasite anti-infective immunity from the viewpoint of immunometabolism.