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Simple Summary: The gut microbiota plays a pivotal role in sustaining human health, especially through its interactions with the immune system. This study examines how the bacterium Lacticaseibacillus rhamnosus responds to cytokines, which are essential for controlling inflammation and are well studied in relation to pathogenic bacteria. However, less is understood about the response of commensal bacteria like L. rhamnosus to these immune factors. Using RNA sequencing, we analyzed the genetic responses of four L. rhamnosus strains to various cytokines, including TNFα, IL-6, IL-8, and IL-10. Our findings indicate that cytokines significantly alter bacterial gene expression, particularly in pathways linked to energy metabolism and stress response. This research advances our understanding of how these bacteria adapt to immune cues, supporting gut health. The results could lead to novel probiotic therapies, offering potential treatments for inflammatory diseases. The interaction between gut microbiota and the host immune system is a complex and understudied field, with cytokines like TNFα, IL-6, IL-8, and IL-10 playing pivotal roles. Commensal bacteria, including lactobacilli, respond to these cytokines through adaptive mechanisms that support their survival and function within the gut. While the influence of cytokines on pathogenic bacteria is well documented, their impact on commensal bacteria, particularly lactobacilli, remains underexplored. This study investigates the transcriptional responses of Lacticaseibacillus rhamnosus strains K32 and R19-3 to various cytokines using next-generation RNA sequencing (RNA-seq). Our findings reveal that cytokines, especially IL-8 and IL-10, significantly alter the L. rhamnosus transcriptome, affecting genes involved in carbohydrate metabolism, stress response, and transcriptional regulation. Notably, IL-8 and IL-10 induce a significant downregulation of genes related to the phosphotransferase system, suggesting a reduction in metabolic activity in response to inflammatory signals. This study unveils a previously unexplored aspect of L. rhamnosus adaptation, highlighting its intricate response to cytokine signals. By modulating gene expression, L. rhamnosus may mitigate the adverse effects of inflammation and promote gut health. These insights could inform the development of targeted probiotic therapies for inflammatory bowel disease (IBD) and other conditions with altered cytokine levels. Our results suggest that co-evolution between a host and gut microbiota enables bacteria to respond to specific cytokines through gene expression changes, revealing a unique and underexplored facet of the interaction between commensal bacteria and the host organism. [ABSTRACT FROM AUTHOR]

Abstract Salmonella Typhimurium (ST) infection in pigs poses a significant threat to animal health and food safety; the intricate mechanisms underlying host–immune responses and pathogen persistence remain poorly understood. To address this knowledge gap, we comprehensively analyzed the peripheral blood transcriptome in piglets infected with ST. We performed histopathological evaluation, blood parameter analysis, advanced RNA-sequencing techniques, and quantitative reverse transcription PCR (RT-qPCR)-based validation. The increasement in the monocyte counts at 2 days post-infection suggested its potential to serve as a hematological marker for ST infection in piglets. Functional and pathway enrichment analyses of the differentially expressed genes highlighted the pivotal roles of innate and adaptive immune responses, notably in pathways associated with Toll-like receptors, NIK/NF-κB signaling, cytokine signaling, and T cell proliferation. RT-qPCR-based validation using peripheral blood mononuclear cells provided additional insights into the immune system dynamics in response to ST infection, revealing the marked elevation of the interleukin (IL)-15, IL-27, and CXCL10 levels being significantly elevated in ST-infected piglets. Our comprehensive analysis underscores the multifaceted impact of ST infection on piglets and offers valuable insights into the host–pathogen interactions and the role of host immune system during ST infection.

Background: High expression of lncRNA LINC00525 is associated with the progressive development of various cancers, including lung adenocarcinoma (LUAD). LncRNAs play regulatory roles in transcription and gene expression. Objectives: This study aimed to investigate, for the first time, the effect of LINC00525 knockdown on the transcriptome and signaling pathways of A549 LUAD cells. Methods: Differentially expressed genes (DEGs) were identified after LINC00525 silencing in A549 cells using the gene expression profile GSE171460. R packages were employed to identify enriched pathways. Hub genes were identified using a PPI network based on the STRING database. The RNAInter and TRRUST databases were used to predict transcription factors (TFs) that interact with LINC00525 and regulate DEGs. Results: LINC00525 knockdown significantly altered the expression of approximately 3,093 genes. The most significantly enriched pathways were the cell cycle and cytokine signaling pathways. All identified hub genes were upregulated, many of which were related to the cytokine signaling pathway, including STAT1, IL6, ISG15, IRF1, IRF7, IFIH1, and IFIT3. According to the GEPIA database, decreased LINC00525 expression showed a positive correlation with increased expression of the hub genes IL6, DDX58, IFIH1, OAS1, OAS2, and IFIT3, supporting the findings of this study. Based on the transcriptional regulatory network, some TFs of DEGs and hub genes may interact with LINC00525. Conclusions: These findings support the positive association between LINC00525 overexpression and tumor growth. LINC00525 may serve as a potential therapeutic target for LUAD. Further research is needed to explore other functional mechanisms of LINC00525. [ABSTRACT FROM AUTHOR]

Salmonella Typhimurium (ST) infection in pigs poses a significant threat to animal health and food safety; the intricate mechanisms underlying host–immune responses and pathogen persistence remain poorly understood. To address this knowledge gap, we comprehensively analyzed the peripheral blood transcriptome in piglets infected with ST. We performed histopathological evaluation, blood parameter analysis, advanced RNA-sequencing techniques, and quantitative reverse transcription PCR (RT-qPCR)-based validation. The increasement in the monocyte counts at 2 days post-infection suggested its potential to serve as a hematological marker for ST infection in piglets. Functional and pathway enrichment analyses of the differentially expressed genes highlighted the pivotal roles of innate and adaptive immune responses, notably in pathways associated with Toll-like receptors, NIK/NF-κB signaling, cytokine signaling, and T cell proliferation. RT-qPCR-based validation using peripheral blood mononuclear cells provided additional insights into the immune system dynamics in response to ST infection, revealing the marked elevation of the interleukin (IL)-15, IL-27, and CXCL10 levels being significantly elevated in ST-infected piglets. Our comprehensive analysis underscores the multifaceted impact of ST infection on piglets and offers valuable insights into the host–pathogen interactions and the role of host immune system during ST infection. [ABSTRACT FROM AUTHOR]

Allergic asthma is a complex inflammatory disorder predominantly orchestrated by T helper 2 (Th2) lymphocytes. The anti-inflammatory protein Clara Cell 10-kDa (CC10), also known as secretoglobin family 1A member 1 (SCGB1A1), shows promise in modulating respiratory diseases. However, its precise role in asthma remains unclear. This study examines the potential of CC10 to suppress allergic asthma inflammation, specifically assessing its regulatory effects on Th2 cell responses and dendritic cells (DCs). Lower CC10 levels in asthma were observed and correlated with increased IgE and lymphocytes. Cc10−/− mice exhibited exacerbated allergic airway inflammation marked by increased inflammatory cell infiltration, Th2 cytokines, serum antigen-specific IgE levels, and airway hyperresponsiveness (AHR) in house dust mite (HDM)-induced models. Conversely, recombinant CC10 significantly attenuated these inflammatory responses. Intriguingly, CC10 did not directly inhibit Th cell activation but significantly downregulated the population of CD11b+CD103− DCs subsets in lungs of asthmatic mice and modulated the immune activation functions of DCs through NF-κB signaling pathway. The mixed lymphocyte response assay revealed that DCs mediated the suppressive effect of CC10 on Th2 cell responses. Collectively, CC10 profoundly mitigates Th2-type allergic inflammation in asthma by modulating lung DC phenotype and functions, highlighting its therapeutic potential for inflammatory airway conditions and other related immunological disorders. [ABSTRACT FROM AUTHOR]

Adeno-associated virus (AAV) based viral vectors are widely used in human gene therapy and form the basis of approved treatments for several genetic diseases. Immune responses to vector and transgene products, however, substantially complicate these applications in clinical practice. The role of innate immune recognition of AAV vectors was initially unclear, given that inflammatory responses early after vector administration were typically mild in animal models. However, more recent research continues to identify innate immune pathways that are triggered by AAV vectors and that serve to provide activation signals for antigen-presenting cells and initiation of adaptive immune responses. Sensing of the AAV genome by the endosomal DNA receptor toll-like receptor 9 (TLR9) promotes early inflammatory response and interferon expression. Thus, activation of the TLR9>MyD88 pathway in plasmacytoid dendritic cells (pDCs) leads to the conditioning of antigen cross-presenting DCs through type I interferon (IFN-I) and ultimately CD8+ T cell activation. Alternatively, pDCs may also promote CD8+ T cell responses in a TLR9-independent manner by the production of IL-1 cytokines, thereby activating the IL-1R1>MyD88 signaling pathway. AAV can induce cytokine expression in monocyte-derived DCs, which in turn increases antibody formation. Binding of AAV capsid to complement components likely further elevates B cell activation. At high systemic vector doses in humans and in non-human primates, AAV vectors can trigger complement activation, with contributions by classical and alternative pathways, leading to severe toxicities. Finally, evidence for activation of TLR2 by the capsid and of additional innate receptors for nucleic acids has been presented. These observations show that AAV vectors can initiate several and likely redundant innate immune pathways resulting in an exaggerated adaptive immune response. [ABSTRACT FROM AUTHOR]

Clinical evidence points to a function for B cell-activating factor (BAFF) in pregnancy. However, direct roles for BAFF-axis members in pregnancy have not been examined. Here, via utility of genetically modified mice, we report that BAFF promotes inflammatory responsiveness and increases susceptibility to inflammation-induced preterm birth (PTB). In contrast, we show that the closely related A proliferation-inducing ligand (APRIL) decreases inflammatory responsiveness and susceptibility to PTB. Known BAFF-axis receptors serve a redundant function in signaling BAFF/APRIL presence in pregnancy. Treatment with anti-BAFF/APRIL monoclonal antibodies or BAFF/APRIL recombinant proteins is sufficient to manipulate susceptibility to PTB. Notably, macrophages at the maternal-fetal interface produce BAFF, while BAFF and APRIL presence divergently shape macrophage gene expression and inflammatory function. Overall, our findings demonstrate that BAFF and APRIL play divergent inflammatory roles in pregnancy and provide therapeutic targets for mitigating risk of inflammation-induced PTB.

Abstract Background Congenital ichthyosis (CI) is a collective group of rare hereditary skin disorders. Patients present with epidermal scaling, fissuring, chronic inflammation, and increased susceptibility to infections. Recently, there is increased interest in the skin microbiome; therefore, we hypothesized that CI patients likely exhibit an abnormal profile of epidermal microbes because of their various underlying skin barrier defects. Among recruited individuals of Southeast Asian ethnicity, we performed skin meta-genomics (i.e., whole-exome sequencing to capture the entire multi-kingdom profile, including fungi, protists, archaea, bacteria, and viruses), comparing 36 CI patients (representing seven subtypes) with that of 15 CI age-and gender-matched controls who had no family history of CI. Results This case–control study revealed 20 novel and 31 recurrent pathogenic variants. Microbiome meta-analysis showed distinct microbial populations, decreases in commensal microbiota, and higher colonization by pathogenic species associated with CI; these were correlated with increased production of inflammatory cytokines and Th17- and JAK/STAT-signaling pathways in peripheral blood mononuclear cells. In the wounds of CI patients, we identified specific changes in microbiota and alterations in inflammatory pathways, which are likely responsible for impaired wound healing. Conclusions Together, this research enhances our understanding of the microbiological, immunological, and molecular properties of CI and should provide critical information for improving therapeutic management of CI patients.

Background: Congenital ichthyosis (CI) is a collective group of rare hereditary skin disorders. Patients present with epidermal scaling, fissuring, chronic inflammation, and increased susceptibility to infections. Recently, there is increased interest in the skin microbiome; therefore, we hypothesized that CI patients likely exhibit an abnormal profile of epidermal microbes because of their various underlying skin barrier defects. Among recruited individuals of Southeast Asian ethnicity, we performed skin meta-genomics (i.e., whole-exome sequencing to capture the entire multi-kingdom profile, including fungi, protists, archaea, bacteria, and viruses), comparing 36 CI patients (representing seven subtypes) with that of 15 CI age-and gender-matched controls who had no family history of CI. Results: This case–control study revealed 20 novel and 31 recurrent pathogenic variants. Microbiome meta-analysis showed distinct microbial populations, decreases in commensal microbiota, and higher colonization by pathogenic species associated with CI; these were correlated with increased production of inflammatory cytokines and Th17- and JAK/STAT-signaling pathways in peripheral blood mononuclear cells. In the wounds of CI patients, we identified specific changes in microbiota and alterations in inflammatory pathways, which are likely responsible for impaired wound healing. Conclusions: Together, this research enhances our understanding of the microbiological, immunological, and molecular properties of CI and should provide critical information for improving therapeutic management of CI patients. [ABSTRACT FROM AUTHOR]

The interaction between gut microbiota and the host immune system is a complex and understudied field, with cytokines like TNFα, IL-6, IL-8, and IL-10 playing pivotal roles. Commensal bacteria, including lactobacilli, respond to these cytokines through adaptive mechanisms that support their survival and function within the gut. While the influence of cytokines on pathogenic bacteria is well documented, their impact on commensal bacteria, particularly lactobacilli, remains underexplored. This study investigates the transcriptional responses of Lacticaseibacillus rhamnosus strains K32 and R19-3 to various cytokines using next-generation RNA sequencing (RNA-seq). Our findings reveal that cytokines, especially IL-8 and IL-10, significantly alter the L. rhamnosus transcriptome, affecting genes involved in carbohydrate metabolism, stress response, and transcriptional regulation. Notably, IL-8 and IL-10 induce a significant downregulation of genes related to the phosphotransferase system, suggesting a reduction in metabolic activity in response to inflammatory signals. This study unveils a previously unexplored aspect of L. rhamnosus adaptation, highlighting its intricate response to cytokine signals. By modulating gene expression, L. rhamnosus may mitigate the adverse effects of inflammation and promote gut health. These insights could inform the development of targeted probiotic therapies for inflammatory bowel disease (IBD) and other conditions with altered cytokine levels. Our results suggest that co-evolution between a host and gut microbiota enables bacteria to respond to specific cytokines through gene expression changes, revealing a unique and underexplored facet of the interaction between commensal bacteria and the host organism.

Interleukin-2 (IL-2) is a critical cytokine for T cell peripheral tolerance and immunity. Here, we review how IL-2 interaction with the high-affinity IL-2 receptor (IL-2R) supports the development and homeostasis of regulatory T cells and contributes to the differentiation of helper, cytotoxic, and memory T cells. A critical element for each T cell population is the expression of CD25 (Il2rα), which heightens the receptor affinity for IL-2. Signaling through the high-affinity IL-2R also reinvigorates CD8+ exhausted T (Tex) cells in response to checkpoint blockade. We consider the molecular underpinnings reflecting how IL-2R signaling impacts these various T cell subsets and the implications for enhancing IL-2-dependent immunotherapy of autoimmunity, other inflammatory disorders, and cancer. Our knowledge concerning the contributions of IL-2 in T cell biology, particularly its role in the development and functional activity of regulatory, effector, and memory T cells and reinvigorating exhausted T cells, continues to advance. These cells depend on distinctive IL-2R signaling thresholds, providing a pharmacological window for the immunotherapy of autoimmunity and cancer. Here, we report on the current knowledge of the functions of IL-2 and its receptor in T cells and how this understanding is transforming therapeutic strategies. [ABSTRACT FROM AUTHOR]

Summary: The essential role of B cells is to produce protective immunoglobulins (Ig) that recognize, neutralize, and clear invading pathogens. This results from the integration of signals provided by pathogens or vaccines and the stimulatory microenvironment within sites of immune activation, such as secondary lymphoid tissues, that drive mature B cells to differentiate into memory B cells and antibody (Ab)‐secreting plasma cells. In this context, B cells undergo several molecular events including Ig class switching and somatic hypermutation that results in the production of high‐affinity Ag‐specific Abs of different classes, enabling effective pathogen neutralization and long‐lived humoral immunity. However, perturbations to these key signaling pathways underpin immune dyscrasias including immune deficiency and autoimmunity or allergy. Inborn errors of immunity that disrupt critical immune pathways have identified non‐redundant requirements for eliciting and maintaining humoral immune memory but concomitantly prevent immune dysregulation. Here, we will discuss our studies on human B cells, and how our investigation of cytokine signaling in B cells have identified fundamental requirements for memory B‐cell formation, Ab production as well as regulating Ig class switching in the context of protective versus allergic immune responses. [ABSTRACT FROM AUTHOR]

Structure and function of therapeutic antibodies can be modulated by a variety of post-translational modifications (PTM). Tyrosine (Tyr) sulfation is a type of negatively charged PTM that occurs during protein trafficking through the Golgi. In this study, we discovered that an anti-interleukin (IL)-4 human IgG1, produced by transiently transfected HEK293 cells, contained a fraction of unusual negatively charged species. Interestingly, the isolated acidic species exhibited a two-fold higher affinity to IL-4 and a nearly four-fold higher potency compared to the main species. Mass spectrometry (MS) showed the isolated acidic species possessed an +80-Dalton from the expected mass, suggesting an occurrence of Tyr sulfation. Consistent with this hypothesis, we show the ability to control the acidic species during transient expression with the addition of Tyr sulfation inhibitor sodium chlorate or, conversely, enriched the acidic species from 30% to 92% of the total antibody protein when the IL-4 IgG was co-transfected with tyrosylprotein sulfotransferase genes. Further MS and mutagenesis analysis identified a Tyr residue at the light chain complementarity-determining region-1 (CDRL-1), which was sulfated specifically. These results together have demonstrated for the first time that Tyr sulfation at CDRL-1 could modulate antibody binding affinity and potency to a human immune cytokine. [ABSTRACT FROM AUTHOR]

Cancer remains one of the leading causes of morbidity and mortality worldwide, necessitating continuous efforts to develop effective therapeutic strategies. Over the years, advancements in our understanding of the complex interplay between the immune system and cancer cells have led to the development of immunotherapies that revolutionize cancer treatment. Cytokines, as key regulators of the immune response, are involved in both the initiation and progression of cancer by affecting inflammation and manipulating multiple intracellular signaling pathways that regulate cell growth, proliferation, and migration. Cytokines, as key regulators of inflammation, have emerged as promising candidates for cancer therapy. This review article aims to provide an overview of the significance of cytokines in cancer development and therapy by highlighting the importance of targeting cytokine signaling pathways as a potential therapeutic approach. [ABSTRACT FROM AUTHOR]

Aims: Expanded hemodialysis (HDx) therapy with improved molecular cut-off dialyzers exerts beneficial effects on lowering uremia-associated chronic systemic microinflammation, a driver of endothelial dysfunction and cardiovascular disease (CVD) in hemodialysis (HD) patients with end-stage renal disease (ESRD). However, studies on the underlying molecular mechanisms are still at an early stage. Here, we identify the (endothelial) transcription factor Krüppel-like factor 2 (KLF2) and its associated molecular signalling pathways as key targets and regulators of uremia-induced endothelial micro-inflammation in the HD/ESRD setting, which is crucial for vascular homeostasis and controlling detrimental vascular inflammation. Methods and results: First, we found that human microvascular endothelial cells (HMECs) and other typical endothelial and kidney model cell lines (e.g. HUVECs, HREC, and HEK) exposed to uremic serum from patients treated with two different hemodialysis regimens in the Permeability Enhancement to Reduce Chronic Inflammation II (PERCI-II) crossover clinical trial - comparing High-Flux (HF) and Medium Cut-Off (MCO) membranes - exhibited strongly reduced expression of vasculoprotective KLF2 with HF dialyzers, while dialysis with MCO dialyzers led to the maintenance and restoration of physiological KLF2 levels in HMECs. Mechanistic follow-up revealed that the strong downmodulation of KLF2 in HMECs exposed to uremic serum was mediated by a dominant engagement of detrimental ERK instead of beneficial AKT signalling, with subsequent AP1-/c-FOS binding in the KLF2 promoter region, followed by the detrimental triggering of pleiotropic inflammatory mediators, while the introduction of a KLF2 overexpression plasmid could restore physiological KLF2 levels and downmodulate the detrimental vascular inflammation in a mechanistic rescue approach. Conclusion: Uremia downmodulates vasculoprotective KLF2 in endothelium, leading to detrimental vascular inflammation, while MCO dialysis with the novel improved HDx therapy approach can maintain physiological levels of vasculoprotective KLF2. [ABSTRACT FROM AUTHOR]

Signal transducer and activator of transcription 5 (STAT5a and STAT5b) are intrinsically critical for normal hematopoiesis but are also expressed in stromal cells. Here, STAT5ab knockout (KO) was generated with a variety of bone marrow hematopoietic and stromal Cre transgenic mouse strains. Vav1-Cre/+STAT5abfl/fl, the positive control for loss of multipotent hematopoietic function, surprisingly dysregulated niche factor mRNA expression, and deleted STAT5ab in CD45neg cells. Single-cell transcriptome analysis of bone marrow from Vav1-Cre/+ wild-type or Vav1-Cre/+STAT5abfl/fl mice showed hematopoietic stem cell (HSC) myeloid commitment priming. Nes+ cells were detected in both CD45neg and CD45+ clusters and deletion of STAT5ab with Nes-Cre caused hematopoietic repopulating defects. To follow up on these promiscuous Cre promoter deletions in CD45neg and CD45+ bone marrow cell populations, more stroma-specific Cre strains were generated and demonstrated a reduction in multipotent hematopoietic progenitors. Functional support for niche-supporting activity was assessed using STAT5-deficient mesenchymal stem cells (MSCs). With Lepr-Cre/+STAT5abfl/fl, niche factor mRNAs were downregulated with validation of reduced IGF-1 and CXCL12 proteins. Furthermore, advanced computational analyses revealed a key role for STAT5ab/Cish balance with Cish strongly co-expressed in MSCs and HSCs primed for differentiation. Therefore, STAT5ab-associated gene regulation supports the bone marrow microenvironment. [ABSTRACT FROM AUTHOR]

This review highlights Receptor Expressed in Lymphoid Tissues (RELT), a Tumor Necrosis Factor Superfamily member, and its two paralogs, RELL1 and RELL2. Collectively, these three proteins are referred to as RELTfms and have gained much interest in recent years due to their association with cancer and other human diseases. A thorough knowledge of their physiological functions, including the ligand for RELT, is lacking, yet emerging evidence implicates RELTfms in a variety of processes including cytokine signaling and pathways that either promote cell death or survival. T cells from mice lacking RELT exhibit increased responses against tumors and increased inflammatory cytokine production, and multiple lines of evidence indicate that RELT may promote an immunosuppressive environment for tumors. The relationship of individual RELTfms in different cancers is not universal however, as evidence indicates that individual RELTfms may be risk factors in certain cancers yet appear to be protective in other cancers. RELTfms are important for a variety of additional processes related to human health including microbial pathogenesis, inflammation, behavior, reproduction, and development. All three proteins have been strongly conserved in all vertebrates, and this review aims to provide a clearer understanding of the current knowledge regarding these interesting proteins. [ABSTRACT FROM AUTHOR]

Interferon-γ (IFNγ) is a critical antitumor cytokine that has varied effects on different cell types. The global effect of IFNγ in the tumor depends on which cells it acts upon and the spatial extent of its spread. Reported measurements of IFNγ spread vary dramatically in different contexts, ranging from nearest-neighbor signaling to perfusion throughout the entire tumor. Here, we apply theoretical considerations to experiments both in vitro and in vivo to study the spread of IFNγ in melanomas. We observe spatially confined niches of IFNγ signaling in 3-D mouse melanoma cultures and human tumors that generate cellular heterogeneity in gene expression and alter the susceptibility of affected cells to T cell killing. Widespread IFNγ signaling only occurs when niches overlap due to high local densities of IFNγ-producing T cells. We measured length scales of ~30 to 40 μm for IFNγ spread in B16 mouse melanoma cultures and human primary cutaneous melanoma. Our results are consistent with IFNγ spread being governed by a simple diffusion-consumption model and offer insight into how the spatial organization of T cells contributes to intratumor heterogeneity in inflammatory signaling, gene expression, and immune-mediated clearance. Solid tumors are often viewed as collections of diverse cellular "neighborhoods": Our work provides a general explanation for such nongenetic cellular variability due to confinement in the spread of immune mediators. [ABSTRACT FROM AUTHOR]

CD8+ T cells and Natural Killer (NK) cells are cytotoxic lymphocytes important in the response to intracellular pathogens and cancer. Their activity depends on the integration of a large set of intracellular and environmental cues, including antigenic signals, cytokine stimulation and nutrient availability. This integration is achieved by signaling hubs, such as the mechanistic target of rapamycin (mTOR). mTOR is a conserved protein kinase that controls cellular growth and metabolism in eukaryotic cells and, therefore, is essential for lymphocyte development and maturation. However, our current understanding of mTOR signaling comes mostly from studies performed in transformed cell lines, which constitute a poor model for comprehending metabolic pathway regulation. Therefore, it is only quite recently that the regulation of mTOR in primary cells has been assessed. Here, we review the signaling pathways leading to mTOR activation in CD8+ T and NK cells, focusing on activation by cytokines. We also discuss how this knowledge can contribute to immunotherapy development, particularly for cancer treatment. [ABSTRACT FROM AUTHOR]

Atopic dermatitis represents a complex and multidimensional interaction that represents potential fields of preventive and therapeutic management. In addition to the treatment armamentarium available for atopic dermatitis, novel drugs targeting significant molecular pathways in atopic dermatitis biologics and small molecules are also being developed given the condition's complex pathophysiology. While most of the patients are expecting better efficacy and long-term control, the response to these drugs would still depend on numerous factors such as complex genotype, diverse environmental triggers and microbiome-derived signals, and, most importantly, dynamic immune responses. This review article highlights the challenges and the recently developed pharmacological agents in atopic dermatitis based on the molecular pathogenesis of this condition, creating a specific therapeutic approach toward a more personalized medicine. [ABSTRACT FROM AUTHOR]

Chronic low-grade inflammation plays an important role in the pathogenesis of type 2 diabetes. Src homology 2 domain-containing tyrosine phosphatase-2 (SHP2) has been reported to play diverse roles in different tissues during the development of metabolic disorders. We previously reported that SHP2 inhibition in macrophages results in increased cytokine production. Here, we investigated the association between SHP2 inhibition in macrophages and the development of metabolic diseases. Unexpectedly, we found that mice with a conditional SHP2 knockout in macrophages (cSHP2-KO) have ameliorated metabolic disorders. cSHP2-KO mice fed a high-fat diet (HFD) gained less body weight and exhibited decreased hepatic steatosis, as well as improved glucose intolerance and insulin sensitivity, compared with HFD-fed WT littermates. Further experiments revealed that SHP2 deficiency leads to hyperactivation of caspase-1 and subsequent elevation of interleukin 18 (IL-18) levels, both in vivo and in vitro Of note, IL-18 neutralization and caspase-1 knockout reversed the amelioration of hepatic steatosis and insulin resistance observed in the cSHP2-KO mice. Administration of two specific SHP2 inhibitors, SHP099 and Phps1, improved HFD-induced hepatic steatosis and insulin resistance. Our findings provide detailed insights into the role of macrophagic SHP2 in metabolic disorders. We conclude that pharmacological inhibition of SHP2 may represent a therapeutic strategy for the management of type 2 diabetes.

Background: The JAK-STAT pathway has been revealed to play a crucial role in the dysregulation of immune responses in autoimmune skin disorders. Ruxolitinib, a selective inhibitor of JAK1 and JAK2, potently suppresses cytokine signaling. Methods: A topical emulgel containing ruxolitinib nanoliposome (RuxoLip) was prepared by thin film hydration method. Then, its physicochemical characteristics were evaluated at 25±2 ̊C/60±5% RH for 12 months. RuxoLip was assessed based on particle characteristics, Scanning Electron Microscopy (SEM), entrapment efficiency (EE), drug loading (DL), and Differential Scanning Calorimetry (DSC). The pH, density, viscosity, microbial assessment, in vitro drug release, and in vivo tape stripping test were evaluated on the emulgel of RuxoLip. Validating the analysis method was performed by UV spectroscopy. Results: Nanoliposomal preparation was successfully formulated with a good particle size (218±2 nm), an EE of 67% and a DL of 8%. The formulation was stable in a long-term condition. SEM showed that liposomes had a regular spherical surface. Moreover, in vitro drug release and the in vivo tape stripping test revealed good absorption and permeation, respectively. Conclusion: The liposome dosage form is anticipated to be a perfect carrier for the topical drug delivery system of ruxolitinib in autoimmune skin disorders.

common chronic liver disease. The prognosis may vary from simple steatosis to more severe outcomes such as nonalcoholic steatohepatitis (NASH), liver cirrhosis, and hepatocellular carcinoma. The understanding of the biological processes leading to NASH is limited and non-invasive diagnostic tools are lacking. Methods: The peripheral immunoproteome in biopsy-proven NAFL (n=35) and NASH patients (n=35) compared to matched, normal-weight healthy controls (n=15) was studied using a proximity extension assay, combined with spatial and single cell hepatic transcriptome analysis. Results: We identified 13 inflammatory serum proteins that, independent of comorbidities and fibrosis stage, distinguished NASH from NAFL. Analysis of coexpression patterns and biological networks further revealed NASH-specific biological perturbations indicative of temporal dysregulation of IL-4/-13, -10, -18, and non-canonical NF-ĸb signaling. Of the identified inflammatory serum proteins, IL-18 and EN-RAGE as well as ST1A1 mapped to hepatic macrophages and periportal hepatocytes, respectively, at the single cell level. The signature of inflammatory serum proteins further permitted identification of biologically distinct subgroups of NASH patients. Conclusion: NASH patients have a distinct inflammatory serum protein signature, which can be mapped to the liver parenchyma, disease pathogenesis, and identifies subgroups of NASH patients with altered liver biology. [ABSTRACT FROM AUTHOR]

The placenta is essential for reproductive success. The murine placenta includes polyploid giant cells that are crucial for its function. Polyploidy occurs broadly in nature but its regulators and significance in the placenta are unknown. We have discovered that many murine placental cell types are polyploid and have identified factors that license polyploidy using single-cell RNA sequencing. Myc is a key regulator of polyploidy and placental development, and is required for multiple rounds of DNA replication, likely via endocycles, in trophoblast giant cells. Furthermore, MYC supports the expression of DNA replication and nucleotide biosynthesis genes along with ribosomal RNA. Increased DNA damage and senescence occur in trophoblast giant cells without Myc, accompanied by senescence in the neighboring maternal decidua. These data reveal Myc is essential for polyploidy to support normal placental development, thereby preventing premature senescence.Our study, combined with available literature, suggests that Myc is an evolutionarily conserved regulator of polyploidy. [ABSTRACT FROM AUTHOR]

Background and aimsNon-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease. The prognosis may vary from simple steatosis to more severe outcomes such as nonalcoholic steatohepatitis (NASH), liver cirrhosis, and hepatocellular carcinoma. The understanding of the biological processes leading to NASH is limited and non-invasive diagnostic tools are lacking.MethodsThe peripheral immunoproteome in biopsy-proven NAFL (n=35) and NASH patients (n=35) compared to matched, normal-weight healthy controls (n=15) was studied using a proximity extension assay, combined with spatial and single cell hepatic transcriptome analysis.ResultsWe identified 13 inflammatory serum proteins that, independent of comorbidities and fibrosis stage, distinguished NASH from NAFL. Analysis of co-expression patterns and biological networks further revealed NASH-specific biological perturbations indicative of temporal dysregulation of IL-4/-13, -10, -18, and non-canonical NF-kβ signaling. Of the identified inflammatory serum proteins, IL-18 and EN-RAGE as well as ST1A1 mapped to hepatic macrophages and periportal hepatocytes, respectively, at the single cell level. The signature of inflammatory serum proteins further permitted identification of biologically distinct subgroups of NASH patients.ConclusionNASH patients have a distinct inflammatory serum protein signature, which can be mapped to the liver parenchyma, disease pathogenesis, and identifies subgroups of NASH patients with altered liver biology.

Introduction: Suppressor of cytokine signaling 3 (SOCS3) is a critical component of the negative feedback regulation that controls signaling by cytokines and other factors thereby ensuring that important processes such as hematopoiesis and inflammation occur at appropriate levels. Methods: To gain further insights into SOCS3 function, the zebrafish socs3b gene was investigated through analysis of a knockout line generated using CRISPR/Cas9-mediated genome editing. Results: Zebrafish socs3b knockout embryos displayed elevated numbers of neutrophils during primitive and definitive hematopoiesis but macrophage numbers were not altered. However, the absence of socs3b reduced neutrophil functionality but enhanced macrophage responses. Adult socs3b knockout zebrafish displayed reduced survival that correlated with an eye pathology involving extensive infiltration of neutrophils and macrophages along with immune cell dysregulation in other tissues. Discussion: These findings identify a conserved role for Socs3b in the regulation of neutrophil production and macrophage activation. [ABSTRACT FROM AUTHOR]

Hyperactive mutation V617F in the JAK2 regulatory pseudokinase domain (JH2) is prevalent in patients with myeloproliferative neoplasms. Here, we identified novel small molecules that target JH2 of JAK2 V617F and characterized binding via biochemical and structural approaches. Screening of 107,600 small molecules resulted in identification of 55 binders to the ATP-binding pocket of recombinant JAK2 JH2 V617F protein at a low hit rate of 0.05%, which indicates unique structural characteristics of the JAK2 JH2 ATP-binding pocket. Selected hits and structural analogs were further assessed for binding to JH2 and JH1 (kinase) domains of JAK family members (JAK1-3, TYK2) and for effects on MPN model cell viability. Crystal structures were determined with JAK2 JH2 wild-type and V617F. The JH2-selective binders were identified in diaminotriazole, diaminotriazine, and phenylpyrazolo-pyrimidone chemical entities, but they showed low-affinity, and no inhibition of MPN cells was detected, while compounds binding to both JAK2 JH1 and JH2 domains inhibited MPN cell viability. X-ray crystal structures of protein-ligand complexes indicated generally similar binding modes between the ligands and V617F or wild-type JAK2. Ligands of JAK2 JH2 V617F are applicable as probes in JAK-STAT research, and SAR optimization combined with structural insights may yield higher-affinity inhibitors with biological activity. [ABSTRACT FROM AUTHOR]

The study examined changes in the plasma proteome, metabolome, and lipidome of N = 14 patients with relapsing-remitting multiple sclerosis (RRMS) initiating treatment with ocrelizumab, assayed at baseline, 6 months, and 12 months. Analyses of >4000 circulating biomarkers identified depletion of B-cell associated proteins as the early effect observed following ocrelizumab (OCR) initiation, accompanied by the reduction in plasma abundance of cytokines and cytotoxic proteins, markers of neuronaxonal damage, and biologically active lipids including ceramides and lysophospholipids, at 6 months. B-cell depletion was accompanied by decreases in B-cell receptor and cytokine signaling but a pronounced increase in circulating plasma B-cell activating factor (BAFF). This was followed by an upregulation of a number of signaling and metabolic pathways at 12 months. Patients with higher baseline brain MRI lesion load demonstrated both higher levels of cytotoxic and structural proteins in plasma at baseline and more pronounced biomarker change trajectories over time. Digital cytometry identified a putative increase in myeloid cells and a pro-inflammatory subset of T-cells. Therapeutic effects of ocrelizumab extend beyond CD20-mediated B-cell lysis and implicate metabolic reprogramming, juxtaposing the early normalization of immune activation, cytokine signaling and metabolite and lipid turnover in periphery with changes in the dynamics of immune cell activation or composition. We identify BAFF increase following CD20 depletion as a tentative compensatory mechanism that contributes to the reconstitution of targeted B-cells, necessitating further research. • Multi-omics on 14 RRMS patients treated with ocrelizumab revealed changes in the plasma proteome, metabolome, and lipidome. • Ocrelizumab reduced B-cell-associated proteins, cytokines, cytotoxic proteins, and markers of neuronal damage at 6 months. • BAFF levels increased significantly following B-cell depletion, suggesting a compensatory mechanism for B-cell reconstitution. • Results suggest that ocrelizumab's therapeutic effects involve metabolic reprogramming and immune system normalization. [ABSTRACT FROM AUTHOR]

IntroductionSuppressor of cytokine signaling 3 (SOCS3) is a critical component of the negative feedback regulation that controls signaling by cytokines and other factors thereby ensuring that important processes such as hematopoiesis and inflammation occur at appropriate levels.MethodsTo gain further insights into SOCS3 function, the zebrafish socs3b gene was investigated through analysis of a knockout line generated using CRISPR/Cas9-mediated genome editing.ResultsZebrafish socs3b knockout embryos displayed elevated numbers of neutrophils during primitive and definitive hematopoiesis but macrophage numbers were not altered. However, the absence of socs3b reduced neutrophil functionality but enhanced macrophage responses. Adult socs3b knockout zebrafish displayed reduced survival that correlated with an eye pathology involving extensive infiltration of neutrophils and macrophages along with immune cell dysregulation in other tissues.DiscussionThese findings identify a conserved role for Socs3b in the regulation of neutrophil production and macrophage activation.

Skeletal muscle atrophy is a prevalent complication in multiple chronic diseases and disuse conditions. Fibroblast growth factor‐inducible 14 (Fn14) is a member of the TNF receptor superfamily and a bona fide receptor of the TWEAK cytokine. Accumulating evidence suggests that Fn14 levels are increased in catabolic conditions as well as during exercise. However, the role of Fn14 in the regulation of skeletal muscle mass and function remains poorly understood. In this study, through the generation of novel skeletal muscle‐specific Fn14‐knockout mice, we have investigated the muscle role of Fn14 in the regulation of exercise capacity and denervation‐induced muscle atrophy. Our results demonstrate that there was no difference in skeletal muscle mass between control and muscle‐specific Fn14‐knockout mice. Nevertheless, the deletion of Fn14 in skeletal muscle significantly improved exercise capacity and resistance to fatigue. This effect of Fn14 deletion is associated with an increased proportion of oxidative myofibers and higher capillaries number per myofiber in skeletal muscle. Furthermore, our results demonstrate that targeted deletion of Fn14 inhibits denervation‐induced muscle atrophy in adult mice. Deletion of Fn14 reduced the expression of components of the ubiquitin‐proteasome system and non‐canonical NF‐kappa B signaling in denervated skeletal muscle, as well as increased the phosphorylation of Akt kinase and FoxO3a transcription factor. Collectively, our results demonstrate that targeted inhibition of Fn14 improves exercise tolerance and inhibits denervation‐induced muscle atrophy in adult mice. [ABSTRACT FROM AUTHOR]

A coding allele of ATG16L1 that increases the risk of Crohn disease (T300A; rs2241880) impairs the interaction between the C-terminal WD40 domain (WDD) and proteins containing a WDD-binding motif, thus specifically inhibiting the unconventional autophagic activities of ATG16L1. In a recent publication we described a novel atypical role of ATG16L1 in the regulation of IL10R (interleukin 10 receptor) trafficking and signaling, an activity that involves direct interaction between the WDD and a target motif present in IL10RB (interleukin 10 receptor subunit beta). Here we show that, unexpectedly, neither the ability of ATG16L1 to interact with IL10RB nor its role in supporting IL10 signaling are altered by the T300A mutation. These results indicate that the ATG16L1T300A allele selectively impairs the interaction between the WDD and a subset of WDD-binding motif versions, suggesting that only a fraction of the unconventional activities mediated by ATG16L1 are required to prevent Crohn disease. Abbreviations: ATG, autophagy related; ATG16L1, autophagy related 16 like 1; BMDMs, bone marrow-derived macrophages; CRISPR, clustered regularly interspaced short palindromic repeats; CSF1/M-CSF, colony stimulating factor 1; FBS, fetal bovine serum; GSH, glutathione; IL10, interleukin 10; IL10R, interleukin 10 receptor; LPS, lipopolysaccharide; MAP1LC3/LC3, microtubule associated protein 1 light chain 3; MEFs, mouse embryonic fibroblasts; PMA, phorbol myristate acetate; p-STAT3: phosphorylated STAT3; qPCR, quantitative polymerase chain reaction; SDS, sodium dodecyl sulfate; sgRNA, single guide RNA; TMEM59, transmembrane protein 59; TNF, tumor necrosis factor; TNFAIP3/A20, TNF alpha induced protein 3; WDD, WD40 domain; WIPI2, WD repeat domain, phosphoinositide interacting 2 [ABSTRACT FROM AUTHOR]

Rasmussen encephalitis (RE) is a rare childhood neurological disease characterized by progressive unilateral loss of function, hemispheric atrophy and drug-resistant epilepsy. Affected brain tissue shows signs of infiltrating cytotoxic T-cells, microglial activation, and neuronal death, implicating an inflammatory disease process. Recent studies have identified molecular correlates of inflammation in RE, but cell-type-specific mechanisms remain unclear. We used single-nucleus RNA-sequencing (snRNA-seq) to assess gene expression across multiple cell types in brain tissue resected from two children with RE. We found transcriptionally distinct microglial populations enriched in RE compared to two age-matched individuals with unaffected brain tissue and two individuals with Type I focal cortical dysplasia (FCD). Specifically, microglia in RE tissues demonstrated increased expression of genes associated with cytokine signaling, interferon-mediated pathways, and T-cell activation. We extended these findings using spatial proteomic analysis of tissue from four surgical resections to examine expression profiles of microglia within their pathological context. Microglia that were spatially aggregated into nodules had increased expression of dynamic immune regulatory markers (PD-L1, CD14, CD11c), T-cell activation markers (CD40, CD80) and were physically located near distinct CD4+ and CD8+ lymphocyte populations. These findings help elucidate the complex immune microenvironment of RE. [ABSTRACT FROM AUTHOR]

Introduction: Fibraurea tinctoria Lour. has long been used in traditional medicine to treat diabetes mellitus (DM). However, a comprehensive scientific understanding of its potential active compounds and underlying pharmacological mechanisms still needs to be unveiled., Objective: This study, therefore, presents a novel approach by integrating metabolomic profiling, pharmacological network, and molecular docking analysis to investigate the potential of F. tinctoria as antidiabetes mellitus., Methods: Active compounds were obtained through analysis using ultrahigh-performance liquid chromatography-quadrupole-orbital ion trap-high resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS) and screening of active compounds using Lipinski rule of five and ADMET parameters. Potential targets of F. tinctoria compounds and DM-related targets were retrieved from public databases, such as DisGeNET, GeneCards, OMIM, PharmaGKB, and TTD. The targets' gene ontology (GO) was created using DAVID and protein-protein interactions using STRING. The plant-organ-compound-target-disease network was constructed using Cytoscape. Then, molecular docking analysis predicted and verified the interactions of essential bioactive compounds of F. tinctoria and DM core targets., Results: The network pharmacology approach identified 35 active compounds, 565 compound-related targets, and 17,289 DM-related targets. EGFR, HSP90AA1, ESR1, HSP90AB1, and GSK3B were the core targets, whereas isolariciresinol, cubebin, corypalmine, (-)-8-oxocanadine, and (+)-N-methylcoclaurine were the most active compounds of F. tinctoria with DM potential. GO functional enrichment analysis revealed 483 biological processes, 485 cellular components, and 463 molecular functions. REACTOME pathway enrichment analysis yielded 463 significantly enriched signaling pathways. Of these pathways, the cytokine signaling in the immune system pathway may play a key role in treating DM. The results of molecular docking analysis showed that the core targets of DM, such as 5gnk, 3o0i, 6psj, 5ucj, and 1q5k, bind stably to the analyzed bioactive compounds of F. tinctoria., Conclusions: This study provides significant insights into the potential mechanism of F. tinctoria in treating DM. The main active compounds of F. tinctoria were found to interact with the core targets (EGFR, HSP90AA1, ESR1, HSP90AB1, and GSK3B) through the cytokine signaling pathway in the immune system, suggesting a potential therapeutic pathway for DM. However, it is essential to note that these findings are preliminary, and further research is necessary to validate them. Those research studies could involve in vitro and in vivo studies to confirm the bioactivity of the identified compounds and their interactions with the core targets. When the findings are confirmed, they could have significant clinical implications, potentially leading to developing new therapeutic strategies for DM., (© 2024 John Wiley & Sons, Ltd.)

Acute myeloid leukemia (AML) is a highly heterogeneous malignancy of the blood and bone marrow, characterized by clonal expansion of myeloid stem and progenitor cells and rapid disease progression. Chemotherapy has been the first-line treatment for AML for more than 30 years. Application of recent high-throughput next-generation sequencing technologies has revealed significant molecular heterogeneity to AML, which in turn has motivated efforts to develop new, targeted therapies. However, due to the high complexity of this disease, including multiple driver mutations and the coexistence of multiple competing tumorigenic clones, the successful incorporation of these new agents into clinical practice remains challenging. These continuing difficulties call for the identification of innovative therapeutic approaches that are effective for a larger cohort of AML patients. Recent studies suggest that chronic immune stimulation and aberrant cytokine signaling act as triggers for AML initiation and progression, facets of the disease which might be exploited as promising targets in AML treatment. However, despite the greater appreciation of cytokine profiles in AML, the exact functions of cytokines in AML pathogenesis are not fully understood. Therefore, unravelling the molecular basis of the complex cytokine networks in AML is a prerequisite to develop new therapeutic alternatives based on targeting cytokines and their receptors. [ABSTRACT FROM AUTHOR]

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has becoming globally public health threat. Recently studies were focus on SARS-CoV-2 RNA to design vaccine and drugs. It was demonstrated that virus RNA could play as sponge to host noncoding RNAs to regulate cellular processes. Bioinformatic research predicted a series of motif on SARS-CoV-2 genome where are targets of human miRNAs. In this study, we used dual-luciferase reporter assays to validate the interaction between 3’UTR of SARS-CoV-2 S (S-3’UTR) gene and bioinformatic predicted targeting miRNAs. The growth of 293T cells and HUVECs with overexpressed S-3’UTR was determined, while miRNAs and IL6, TNF-a levels were checked in this condition. Then, miR-296 and miR-602 mimic were introduced into 293T cells and HUVECs with overexpressed S3’UTR, respectively, to reveal the underlying regulation mechanism. In results, we screened 19 miRNAs targeting the S-3’UTR, including miR-296 and miR602. In 293T cell, S-3’UTR could inhibit 293T cell growth through downregulation of miR-296. By reducing miR-602, S-3’UTR could induce HUVECs cell proliferation, alter the cell cycle, reduce apoptosis, and enhanced IL6 and TNF-alevel. In conclusion, SARS-CoV-2 RNA could play as sponge of host miRNA to disturb cell growth and cytokine signaling. It suggests an important clue for designing COVID-19 drug and vaccine. [ABSTRACT FROM AUTHOR]

Simple Summary: An uncontrollable loss in the skeletal muscle of cancer patients which leads to a significant reduction in body weight is clinically referred to as cancer cachexia (CC). While factors derived from the tumor environment which trigger various signaling pathways have been identified, not much progress has been made clinically to effectively prevent muscle loss. Deeper insights into the transcriptional and epigenetic regulation of muscle catabolic genes may shed light on key regulators which can be targeted to develop new therapeutic avenues. Cancer cachexia (CC) is a multifactorial syndrome characterized by a significant reduction in body weight that is predominantly caused by the loss of skeletal muscle and adipose tissue. Although the ill effects of cachexia are well known, the condition has been largely overlooked, in part due to its complex etiology, heterogeneity in mediators, and the involvement of diverse signaling pathways. For a long time, inflammatory factors have been the focus when developing therapeutics for the treatment of CC. Despite promising pre-clinical results, they have not yet advanced to the clinic. Developing new therapies requires a comprehensive understanding of how deregulated signaling leads to catabolic gene expression that underlies muscle wasting. Here, we review CC-associated signaling pathways and the transcriptional cascade triggered by inflammatory cytokines. Further, we highlight epigenetic factors involved in the transcription of catabolic genes in muscle wasting. We conclude with reflections on the directions that might pave the way for new therapeutic approaches to treat CC. [ABSTRACT FROM AUTHOR]

Aberrant activation of CD4 T H 2 cells and excessive production of T H 2 cytokines such as IL-4 and IL-13 have been implicated in the pathogenesis of allergic diseases. Generally, IL-4 and IL-13 utilize Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathways for induction of inflammatory gene expression and the effector functions associated with disease pathology in many allergic diseases. However, it is increasingly clear that JAK/STAT pathways activated by IL-4/IL-13 can themselves be modulated in the presence of other intracellular signaling programs, thereby changing the overall tone and/or magnitude of IL-4/IL-13 signaling. Apart from direct activation of the canonic JAK/STAT pathways, IL-4 and IL-13 also induce proinflammatory gene expression and effector functions through activation of additional signaling cascades. These alternative signaling cascades contribute to several specific aspects of IL-4/IL-13–associated cellular and molecular responses. A more complete understanding of IL-4/IL-13 signaling pathways, including the precise conditions under which noncanonic signaling pathways are activated, and the impact of these pathways on cellular- and host-level responses, will better allow us to design agents that target specific pathologic outcomes or tailor therapies for the treatment of uncommon disease endotypes. [ABSTRACT FROM AUTHOR]

Demyelination is one of the pathological outcomes that occur immediately following spinal cord injury. Protection of oligodendrocytes against death/apoptosis proves to be beneficial for the preservation of neurological functions. Suppressors of cytokine signaling 1 protein inhibit the harmful effects of several inflammatory cytokines on oligodendrocytes, but its roles in spinal cord injury (SCI) induced apoptosis of oligodendrocytes remain unclear. We cloned suppressors of cytokine signaling 1 cDNA from Gekko japonicus (Japanese gecko) and analyzed the protein structure revealing the conserved domains contained in other vertebrate suppressors of cytokine signaling 1 proteins. The gecko suppressors of cytokine signaling 1 protein expression were increased in the injured spinal cord following gecko tail amputation and displayed colocalization with oligodendrocytes. The enforced expression of gecko suppressors of cytokine signaling 1 by adenovirus in the Gsn3 gecko oligodendrocyte cell line demonstrated that gecko suppressors of cytokine signaling 1 significantly suppressed cell apoptosis-induced by glucose deprivation. Determination of apoptosis-related proteins revealed that gecko suppressors of cytokine signaling 1 was able to activate extracellular regulated protein kinases (ERK) and serine/threonine protein kinases (Akt). The results presented a distinct protective role of gecko suppressors of cytokine signaling 1 in the regenerative model of the spinal cord, which may provide new cues for central nervous system repair in mammals.

Peptidomimetics of Suppressors of cytokine signaling 1 (SOCS1) protein demonstrated valid therapeutic potentials as anti-inflammatory agents. Indeed, SOCS1 has a small kinase inhibitory region (KIR) primarily involved in the inhibition of the JAnus Kinase/Signal Transducer and Activator of Transcription (JAK/STAT) pathway Herein, on the basis of previous investigations on a potent mimetic of KIR-SOCS1, named PS5, we designed and evaluated the SAR (Structure Activity Relationship) features of two xylene-based macrocycles analogues of PS5. These novel compounds bear thiol-xylene linkages with mono- and bi-cyclic scaffolds: they were in vitro functionally investigated toward JAK2 catalytic domain, as ligands with microscale thermophoresis (MST) and as inhibitors through LC-MS analyses. To evaluate structural properties Circular Dichroism (CD) and Nuclear Magnetic Resonance (NMR) spectroscopies were employed along with serum stability assays. Results indicated that a monocycle scaffold is well-tolerated by PS5 sequence enhancing the affinity toward the kinase with a K D in the low micromolar range and providing consistent inhibitory effects of the catalytic activity, which were evaluated for the first time in the case of SOCS1 mimetics. Conformationally, the presence of xylene scaffold affects the flexibility of the compounds and their stabilities to proteases degradation. This study contributes to the understanding of the factors necessary for accurately mimicking the inhibitory mechanism of SOCS1 protein towards JAK2 and to the translation of proteomimetics into drugs. [Display omitted] • SOCS1-kinase inhibitor region (KIR) is crucial to inhibit JAK2. • Novel cyclic peptidomimetics of SOCS1-KIR. • Insertion of unnatural aromatic cyclic scaffold: xylene. • SAR studies of their recognition toward JAK2. • Crucial role of aromatic interactions to enhance the affinity of SOCS1 mimetics toward JAK2. [ABSTRACT FROM AUTHOR]

JAK1 is a critical effector of pro-inflammatory cytokine signaling and plays important roles in immune function, while abnormal JAK1 activity has been linked to immunological and neoplastic diseases. Specific functions of JAK1 in the context of hematopoiesis, and specifically within hematopoietic stem cells (HSCs), have not clearly been delineated. Here, we show that conditional Jak1 loss in HSCs reduces their self-renewal and markedly alters lymphoid/myeloid differentiation in vivo. Jak1-deficient HSCs exhibit decreased competitiveness in vivo and are unable to rescue hematopoiesis in the setting of myelosuppression. They exhibit increased quiescence, an inability to enter the cell cycle in response to hematopoietic stress, and a marked reduction in cytokine sensing, including in response to type I interferons and IL-3. Moreover, Jak1 loss is not fully rescued by expression of a constitutively active Jak2 allele. Together, these data highlight an essential role for Jak1 in HSC homeostasis and stress responses.

Acute myeloid leukemia (AML) is a highly heterogeneous malignancy of the blood and bone marrow, characterized by clonal expansion of myeloid stem and progenitor cells and rapid disease progression. Chemotherapy has been the first-line treatment for AML for more than 30 years. Application of recent high-throughput next-generation sequencing technologies has revealed significant molecular heterogeneity to AML, which in turn has motivated efforts to develop new, targeted therapies. However, due to the high complexity of this disease, including multiple driver mutations and the coexistence of multiple competing tumorigenic clones, the successful incorporation of these new agents into clinical practice remains challenging. These continuing difficulties call for the identification of innovative therapeutic approaches that are effective for a larger cohort of AML patients. Recent studies suggest that chronic immune stimulation and aberrant cytokine signaling act as triggers for AML initiation and progression, facets of the disease which might be exploited as promising targets in AML treatment. However, despite the greater appreciation of cytokine profiles in AML, the exact functions of cytokines in AML pathogenesis are not fully understood. Therefore, unravelling the molecular basis of the complex cytokine networks in AML is a prerequisite to develop new therapeutic alternatives based on targeting cytokines and their receptors.

Although aberrant activation of the KRAS and PI3K pathway alongside TP53 mutations account for frequent aberrations in human gastric cancers, neither the sequence nor the individual contributions of these mutations have been clarified. Here, we establish an allelic series of mice to afford conditional expression in the glandular epithelium of Kras G12D ; Pik3ca H1047R or Trp53 R172H and/or ablation of Pten or Trp53. We find that Kras G12D ; Pik3ca H1047R is sufficient to induce adenomas and that lesions progress to carcinoma when also harboring Pten deletions. An additional challenge with either Trp53 loss- or gain-of-function alleles further accelerated tumor progression and triggered metastatic disease. While tumor-intrinsic STAT3 signaling in response to gp130 family cytokines remained as a gatekeeper for all stages of tumor development, metastatic progression required a mutant Trp53 -induced interleukin (IL)-11 to IL-6 dependency switch. Consistent with the poorer survival of patients with high IL-6 expression, we identify IL-6/STAT3 signaling as a therapeutic vulnerability for TP53-mutant gastric cancer. [Display omitted] • Mutant TP53 licenses progression to invasive stomach carcinoma with synchronous metastasis • Gain- and loss-of-function TP53 mutants advance gastric cancer upon loss of heterozygosity • Gastric cancer's STAT3 addiction switches from IL-11 to IL-6 dependency when being TP53 mutant Huber et al. demonstrate that gain-of-function and loss-of-expression TP53 mutations drive gastric disease progression to aggressive carcinomas with synchronous metastasis. While STAT3 signaling remains rate limiting throughout gastric cancer progression, its cytokine dependency switches from IL-11 to IL-6 in response to the TP53 mutations observed during the transition to carcinomas. [ABSTRACT FROM AUTHOR]

Prolonged activation of the type I interferon (IFN-I) pathway leads to autoimmune diseases such as systemic lupus erythematosus (SLE). Metabolic regulation of cytokine signaling is critical for cellular homeostasis. Through metabolomics analyses of IFN-β-activated macrophages and an IFN-stimulated-response-element reporter screening, we identified spermine as a metabolite brake for Janus kinase (JAK) signaling. Spermine directly bound to the FERM and SH2 domains of JAK1 to impair JAK1-cytokine receptor interaction, thus broadly suppressing JAK1 phosphorylation triggered by cytokines IFN-I, IFN-II, interleukin (IL)-2, and IL-6. Peripheral blood mononuclear cells (PBMCs) from individuals with SLE showing decreased spermine concentrations exhibited enhanced IFN-I and lupus gene signatures. Spermine treatment attenuated autoimmune pathogenesis in SLE and psoriasis mice and reduced IFN-I signaling in monocytes from individuals with SLE. We synthesized a spermine derivative (spermine derivative 1 [SD1]) and showed that it had a potent immunosuppressive function. Our findings reveal spermine as a metabolic checkpoint for cellular homeostasis and a potential immunosuppressive molecule for controlling autoimmune disease. [Display omitted] • Spermine restrains JAK1-mediated type I/II cytokine signaling • Spermine occupies JAK1 N-terminal pockets to limit its binding to the receptors • Low intracellular spermine enhances ISG and lupus signatures in SLE PBMCs • Spermine and the derivative SD1 attenuate pathological features in autoimmune mice Immunometabolites are important in autoinflammation and autoimmune disorders but need to be further identified. Xu et al. reveal that spermine acts as an endogenous JAK1 inhibitor by directly binding JAK1 to restrain type I/II cytokine responses. In vivo administration of spermine and the derivative SD1 attenuates lupus and psoriasis features. [ABSTRACT FROM AUTHOR]

We hereby describe the process of design and selection of nonantibody protein binders mimicking cytokine signaling. We chose to mimic signaling of IFN‐λ1, type 3 interferon (also known as IL‐29) for its novelty and the importance of its biological functions. All four known interferons λ signal through binding to the extracellular domains of IL‐28 receptor 1 (IL‐28R1) and IL‐10 receptor 2 (IL‐10R2). Our binders were therefore trained to bind both receptors simultaneously. The bifunctional binder molecules were developed by yeast display, a method of directed evolution. The signaling capacity of the bivalent binders was tested by measuring phosphorylation of the JAK/STAT signaling pathway and production of mRNA of six selected genes naturally induced by IFN‐ λ1 in human cell lines. The newly developed bivalent binders offer opportunities to study cytokine‐related biological functions and modulation of the cell behavior by receptor activation on the cell surfaces alternative to the use of natural IFN‐λ. [ABSTRACT FROM AUTHOR]

SOCS3 (suppressor of cytokine signaling 3) protein suppresses cytokine-induced inflammation and its deletion in neurons or immune cells increases the pathological growth of blood vessels. Recently, we designed several SOCS3 peptidomimetics by assuming as template structures the interfacing regions of the ternary complex constituted by SOCS3, JAK2 (Janus Kinase 2) and gp130 (glycoprotein 130) proteins. A chimeric peptide named KIRCONG chim, including non-contiguous regions demonstrated able to bind to JAK2 and anti-inflammatory and antioxidant properties in VSMCs (vascular smooth muscle cells). With the aim to improve drug-like features of KIRCONG, herein we reported novel cyclic analogues bearing different linkages. In detail, in two of them hydrocarbon cycles of different lengths were inserted at positions i/i+5 and i/i+7 to improve helical conformations of mimetics. Structural features of cyclic compounds were investigated by CD (Circular Dichroism) and NMR (Nuclear Magnetic Resonance) spectroscopies while their ability to bind to catalytic domain of JAK2 was assessed through MST (MicroScale Thermophoresis) assay as well as their stability in biological serum. Overall data indicate a crucial role exerted by the length and the position of the cycle within the chimeric structure and could pave the way to the miniaturization of SOCS3 protein for therapeutic aims. [ABSTRACT FROM AUTHOR]