m(6)A methyltransferase METTL3 relieves cognitive impairment of hyperuricemia mice via inactivating MyD88/NF-κB pathway mediated NLRP3-ASC-Caspase1 inflammasome.

BACKGROUND: Recent studies have uncovered that hyperuricemia (HUA) leads to cognitive deficits, which are accompanied by neuronal damage and neuroinflammation. Here, we aim to explore the role of methyltransferase-like 3 (METTL3) in HUA-mediated neuronal apoptosis and microglial inflammation. METHODS: A HUA mouse model was constructed. The spatial memory ability of the mice was assessed by the Morris water maze experiment (MWM), and neuronal apoptosis was analyzed by the TdT-mediated dUTP nick end labeling (TUNEL) assay. Besides, enzyme-linked immunosorbent assay (ELISA) was utilized to measure the contents of inflammatory factors (IL-1ß, IL-6, and TNF-α) and oxidative stress markers (MDA, SOD, and CAT) in the serum of mice. In vitro, the mouse hippocampal neuron (HT22) and microglia (BV2) were treated with uric acid (UA). Flow cytometry was applied to analyze HT22 and BV2 cell apoptosis, and ELISA was conducted to observe neuroinflammation and oxidative stress. In addition, the expression of MyD88, p-NF-κB, NF-κB, NLRP3, ASC and Caspase1 was determined by Western blot. RESULTS: METTL3 and miR-124-3p were down-regulated, while the MyD88-NF-κB pathway was activated in the HUA mouse model. UA treatment induced neuronal apoptosis in HT22 and stimulated microglial activation in BV2. Overexpressing METTL3 alleviated HT22 neuronal apoptosis and resisted the release of inflammatory cytokines and oxidative stress mediators in BV2 cells. METTL3 repressed MyD88-NF-κB and NLRP3-ASC-Caspase1 inflammasome. In addition, METTL3 overexpression enhanced miR-124-3p expression, while METTL3 knockdown aggravated HT22 cell apoptosis and BV2 cell overactivation. CONCLUSION: METTL3 improves neuronal apoptosis and microglial activation in the HUA model by choking the MyD88/NF-κB pathway and up-regulating miR-124-3p.

Microbial Phagocytic Receptors and Their Potential Involvement in Cytokine Induction in Macrophages.

Phagocytosis is an essential process for the uptake of large (>0.5 µm) particulate matter including microbes and dying cells. Specialized cells in the body perform phagocytosis which is enabled by cell surface receptors that recognize and bind target cells. Professional phagocytes play a prominent role in innate immunity and include macrophages, neutrophils and dendritic cells. These cells display a repertoire of phagocytic receptors that engage the target cells directly, or indirectly via opsonins, to mediate binding and internalization of the target into a phagosome. Phagosome maturation then proceeds to cause destruction and recycling of the phagosome contents. Key subsequent events include antigen presentation and cytokine production to alert and recruit cells involved in the adaptive immune response. Bridging the innate and adaptive immunity, macrophages secrete a broad selection of inflammatory mediators to orchestrate the type and magnitude of an inflammatory response. This review will focus on cytokines produced by NF-κB signaling which is activated by extracellular ligands and serves a master regulator of the inflammatory response to microbes. Macrophages secrete pro-inflammatory cytokines including TNFα, IL1ß, IL6, IL8 and IL12 which together increases vascular permeability and promotes recruitment of other immune cells. The major anti-inflammatory cytokines produced by macrophages include IL10 and TGFß which act to suppress inflammatory gene expression in macrophages and other immune cells. Typically, macrophage cytokines are synthesized, trafficked intracellularly and released in response to activation of pattern recognition receptors (PRRs) or inflammasomes. Direct evidence linking the event of phagocytosis to cytokine production in macrophages is lacking. This review will focus on cytokine output after engagement of macrophage phagocytic receptors by particulate microbial targets. Microbial receptors include the PRRs: Toll-like receptors (TLRs), scavenger receptors (SRs), C-type lectin and the opsonic receptors. Our current understanding of how macrophage receptor stimulation impacts cytokine production is largely based on work utilizing soluble ligands that are destined for endocytosis. We will instead focus this review on research examining receptor ligation during uptake of particulate microbes and how this complex internalization process may influence inflammatory cytokine production in macrophages.

Moderate Exercise Inhibits Age-Related Inflammation, Liver Steatosis, Senescence, and Tumorigenesis.

Age-related chronic inflammation promotes cellular senescence, chronic disease, cancer, and reduced lifespan. In this study, we wanted to explore the effects of a moderate exercise regimen on inflammatory liver disease and tumorigenesis. We used an established model of spontaneous inflammaging, steatosis, and cancer (nfkb1-/- mouse) to demonstrate whether 3 mo of moderate aerobic exercise was sufficient to suppress liver disease and cancer development. Interventional exercise when applied at a relatively late disease stage was effective at reducing tissue inflammation (liver, lung, and stomach), oxidative damage, and cellular senescence, and it reversed hepatic steatosis and prevented tumor development. Underlying these benefits were transcriptional changes in enzymes driving the conversion of tryptophan to NAD+, this leading to increased hepatic NAD+ and elevated activity of the NAD+-dependent deacetylase sirtuin. Increased SIRT activity was correlated with enhanced deacetylation of key transcriptional regulators of inflammation and metabolism, NF-κB (p65), and PGC-1α. We propose that moderate exercise can effectively reprogram pre-established inflammatory and metabolic pathologies in aging with the benefit of prevention of disease.

Attenuation of canonical NF-κB signaling maintains function and stability of human Treg.

Nuclear factor 'κ-light-chain-enhancer' of activated B cells (NF-κB) signaling is a signaling pathway used by most immune cells to promote immunostimulatory functions. Recent studies have indicated that regulatory T cells (Treg) differentially integrate TCR-derived signals, thereby maintaining their suppressive features. However, the role of NF-κB signaling in the activation of human peripheral blood (PB) Treg has not been fully elucidated so far. We show that the activity of the master transcription factor forkhead box protein 3 (FOXP3) attenuates p65 phosphorylation and nuclear translocation of the NF-κB proteins p50, p65, and c-Rel following activation in human Treg. Using pharmacological and genetic inhibition of canonical NF-κB signaling in FOXP3-transgenic T cells and PB Treg from healthy donors as well as Treg from a patient with a primary NFKB1 haploinsufficiency, we validate that Treg activation and suppressive capacity is independent of NF-κB signaling. Additionally, repression of residual NF-κB signaling in Treg further enhances interleukin-10 (IL-10) production. Blockade of NF-κB signaling can be exploited for the generation of in vitro induced Treg (iTreg) with enhanced suppressive capacity and functional stability. In this respect, dual blockade of mammalian target of rapamycin (mTOR) and NF-κB signaling was accompanied by enhanced expression of the transcription factors FOXP1 and FOXP3 and demethylation of the Treg-specific demethylated region compared to iTreg generated under mTOR blockade alone. Thus, we provide first insights into the role of NF-κB signaling in human Treg. These findings could lead to strategies for the selective manipulation of Treg and the generation of improved iTreg for cellular therapy.

Immunomodulatory effects of fucosylated chondroitin sulfate from Stichopus chloronotus on RAW 264.7 cells.

Sea cucumbers were nutritional food and traditional Chinese medicine. In this study, fucosylated chondroitin sulfate from sea cucumber Stichopus chloronotus (fCS-Sc), a potential anticoagulant agent and immunological adjuvant, was investigated for its immune activation effects on RAW 264.7 macrophage for the first time. The results indicated that fCS-Sc could significantly promote the proliferation, the pinocytic activity of RAW 264.7 cells, and the production of NO, TNF-α, IL-1ß, and IL-6. The fluorescence labeling assay indicated that fCS-Sc could bind to the macrophage. Moreover, the specific pattern recognition receptor inhibition assays showed that toll-like receptor 4 (TLR4) and TLR2 were involved in the recognition of fCS-Sc. Western blot assays indicated that fCS-Sc could induce degradation of cytoplasm IκB-α, and promotion of NF-κB p65 subunit translocation to nucleus, leading to a functional improvement of macrophage through NF-κB pathway. The results suggested that fCS-Sc might served as a promising candidate of immunomodulator.

Deep phenotyping of synovial molecular signatures by integrative systems analysis in rheumatoid arthritis.

OBJECTIVE: RA encompasses a complex, heterogeneous and dynamic group of diseases arising from molecular and cellular perturbations of synovial tissues. The aim of this study was to decipher this complexity using an integrative systems approach and provide novel insights for designing stratified treatments. METHODS: An RNA sequencing dataset of synovial tissues from 152 RA patients and 28 normal controls was imported and subjected to filtration of differentially expressed genes, functional enrichment and network analysis, non-negative matrix factorization, and key driver analysis. A naïve Bayes classifier was applied to the independent datasets to investigate the factors associated with treatment outcome. RESULTS: A matrix of 1241 upregulated differentially expressed genes from RA samples was classified into three subtypes (C1-C3) with distinct molecular and cellular signatures. C3 with prominent immune cells and proinflammatory signatures had a stronger association with the presence of ACPA and showed a better therapeutic response than C1 and C2, which were enriched with neutrophil and fibroblast signatures, respectively. C2 was more occupied by synovial fibroblasts of destructive phenotype and carried highly expressed key effector molecules of invasion and osteoclastogenesis. CXCR2, JAK3, FYN and LYN were identified as key driver genes in C1 and C3. HDAC, JUN, NFKB1, TNF and TP53 were key regulators modulating fibroblast aggressiveness in C2. CONCLUSIONS: Deep phenotyping of synovial heterogeneity captured comprehensive and discrete pathophysiological attributes of RA regarding clinical features and treatment response. This result could serve as a template for future studies to design stratified approaches for RA patients.

Comparative anti-inflammatory effects of plant- and marine-derived omega-3 fatty acids explored in an endothelial cell line.

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) lower risk of cardiovascular disease. The primary source of EPA and DHA is fatty fish. Plant-derived alpha linolenic acid (ALA) and stearidonic acid (SDA) could provide sustainable land-based alternatives, but their functionality is underexplored. Omega-3 fatty acids (n-3 FAs) may influence atherogenic processes through changing endothelial cell (EC) function and lowering inflammation. This study compared effects of marine- and plant-derived n-3 FAs on EC inflammatory responses. EA.hy926 cells were exposed to ALA, SDA, EPA or DHA prior to stimulation with tumor necrosis factor (TNF)-α. All FAs were shown to be incorporated into ECs in a dose-dependent manner. SDA (50 µM) decreased both production and cell-surface expression of intercellular adhesion molecule (ICAM)-1; however EPA and DHA resulted in greater reduction of ICAM-1 production and expression. EPA and DHA also significantly lowered production of monocyte chemoattractant protein 1, interleukin (IL)-6 and IL-8. ALA, SDA and DHA (50 µM) all reduced adhesion of THP-1 monocytes to EA.hy926 cells. DHA significantly decreased nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB)p105 gene expression and phosphorylated NFκBp65 protein. Both EPA and DHA (50 µM) significantly decreased cyclooxygenase (COX)-2 protein. Thus, both marine-derived n-3 FAs, particularly DHA, had potent anti-inflammatory effects in this EC model. Of the plant-derived n-3 FAs, SDA showed the greatest inhibition of inflammation. Although neither ALA nor SDA reproduced the anti-inflammatory effects of EPA and DHA in this model, there is some potential for SDA to be a sustainable anti-inflammatory alternative to the marine n-3 FAs.

NF-κB p50-deficient immature myeloid cell (p50-IMC) adoptive transfer slows the growth of murine prostate and pancreatic ductal carcinoma.

BACKGROUND: Macrophages and dendritic cells lacking the transcription factor nuclear factor kappa B p50 are skewed toward a proinflammatory phenotype, with increased cytokine expression and enhanced T cell activation; additionally, murine melanoma, fibrosarcoma, colon carcinoma, and glioblastoma grow slower in p50-/- mice. We therefore evaluated the efficacy of p50-negative immature myeloid cells (p50-IMCs) adoptively transferred into tumor-bearing hosts. Immature cells were used to maximize tumor localization, and pretreatment with 5-fluorouracil (5FU) was examined due to its potential to impair marrow production of myeloid cells, to target tumor myeloid cells and to release tumor neoantigens. METHODS: Wild-type (WT)-IMC or p50-IMC were generated by culturing lineage-negative marrow cells from WT or p50-/- mice in media containing thrombopoietin, stem cell factor and Flt3 ligand for 6 days followed by monocyte colony-stimulating factor for 1 day on ultralow attachment plates. Mice inoculated with Hi-Myc prostate cancer (PCa) cells or K-RasG12D pancreatic ductal carcinoma (PDC)-luciferase cells received 5FU followed 5 days later by three doses of 107 immature myeloid cells (IMC) every 3-4 days. RESULTS: PCa cells grew slower in p50-/- mice, and absence of host p50 prolonged the survival of mice inoculated orthotopically with PDC cells. IMC from Cytomegalovirus (CMV)-luciferase mice localized to tumor, nodes, spleen, marrow, and lung. 5FU followed by p50-IMC slowed PCa and PDC tumor growth, ~3-fold on average, in contrast to 5FU followed by WT-IMC, 5FU alone or p50-IMC alone. Slowed tumor growth was evident for 93% of PCa but only 53% of PDC tumors; we therefore focused on PCa for additional IMC analyses. In PCa, p50-IMC matured into F4/80+ macrophages, as well as CD11b+F4/80-CD11c+ conventional dendritic cells (cDCs). In both tumor and draining lymph nodes, p50-IMC generated more macrophages and cDCs than WT-IMC. Activated tumor CD8+ T cells were increased fivefold by p50-IMC compared with WT-IMC, and antibody-mediated CD8+ T cell depletion obviated slower tumor growth induced by 5FU followed by p50-IMC. CONCLUSIONS: 5FU followed by p50-IMC slows the growth of murine prostate and pancreatic carcinoma and depends on CD8+ T cell activation. Deletion of p50 in patient-derived marrow CD34+ cells and subsequent production of IMC for adoptive transfer may contribute to the therapy of these and additional cancers.

Late-Onset Antibody Deficiency Due to Monoallelic Alterations in NFKB1.

Adult-onset primary immunodeficiency is characterized by recurrent infections, hypogammaglobulinemia, and poor antibody response to vaccines. In this study, we have analyzed targeted gene panel sequencing results of 270 patients diagnosed with antibody deficiency and identified five disease-associated variants in NFKB1 in five unrelated families. We detected two single base pair deletions and two single base pair insertions, causing severe protein truncations, and one missense mutation. Immunoblotting, lymphocyte stimulation, immunophenotyping, and ectopic expression assays demonstrated the functional relevance of NFKB1 mutations. Besides antibody deficiency, clinical manifestations included infections, autoimmune features, lymphoproliferation, lymphoma, Addison's disease, type 2 diabetes and asthma. Although partial clinical penetrance was observed in almost all pedigrees, all carriers presented a deficiency in certain serum immunoglobulins and the majority showed a lack of memory B cells (CD19+CD27+). Among all tested genes, NFKB1 alterations were the most common monoallelic cause of antibody deficiency in our cohort.

Heightened TLR7/9-Induced IL-10 and CXCL13 Production with Dysregulated NF-ҝB Activation in CD11chiCD11b+ Dendritic Cells in NZB/W F1 Mice.

Systemic lupus erythematosus (SLE) is a chronic, multifactorial autoimmune disease that predominantly affects young females. Dysregulation of different immune cell populations leads to self-tolerance breakdown and subsequent multiple organ damage as the disease develops. Plasmacytoid dendritic cells (pDCs) are potent producers of type I interferon (IFN), while myeloid dendritic cells (mDCs) are more specialized in antigen presentations. We have previously reported that bone-marrow (BM)-derived pDCs from the murine lupus model New Zealand black/white F1 (BWF1) possess abnormalities. Therefore, this study continues to investigate what aberrant properties peripheral pDCs and mDCs possess in BWF1 and how they mediate SLE progression, by comparing their properties in pre-symptomatic and symptomatic mice. Results showed that CD11chiCD11b+ myeloid DCs expanded during the disease state with down-regulation of co-stimulatory molecules and major histocompatibility complex class II molecules (MHC II), but their capacity to stimulate T cells was not hampered. During the disease state, this subset of mDCs displayed heightened toll-like receptors 7 and 9 (TLR 7/9) responses with increased interleukin 10 (IL-10) and C-X-C motif chemokine ligand 13 (CXCL13) expressions. Moreover, the expressions of myeloid differentiation primary response 88 (Myd88) and nuclear factor kappa B subunit 1 (Nfkb1) were higher in CD11chiCD11b+ DCs at the disease stage, leading to higher nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) p65 phosphorylation activity. In summary, we reported aberrant phenotypic properties with enhanced TLR7/9 responses of CD11chiCD11b+ DCs in SLE mediated by aberrant NF-κB signaling pathway. Our findings add additional and novel information to our current understanding of the role of DCs in lupus immunopathogenesis. Lastly, molecular candidates in the NF-κB pathway should be exploited for developing therapeutic targets for SLE.

Statins can suppress DC-mediated Th2 responses through the repression of OX40-ligand and CCL17 expression.

DCs and epithelial cell-derived thymic stromal lymphopoietin (TSLP) have pivotal roles in allergic inflammation. TSLP stimulates myeloid DCs to express OX40-ligand (OX40L) and CCL17, which trigger and maintain Th2 cell responses. We have previously shown that statins, which are HMG-CoA reductase inhibitors, have the ability to suppress type I IFN production by plasmacytoid DCs. Here, we extended our previous work to examine the immunomodulatory effect of statins on allergic responses, particularly the TSLP-dependent Th2 pathway induced by myeloid DCs. We found that treatment of TSLP-stimulated DCs with either pitavastatin or simvastatin suppressed both the DC-mediated inflammatory Th2 cell differentiation and CRTH2+ CD4+ memory Th2 cell expansion and also repressed the expressions of OX40L and CCL17 by DCs. These inhibitory effects of statins were mimicked by treatment with either a geranylgeranyl-transferase inhibitor or Rho-kinase inhibitor and were counteracted by the addition of mevalonate, suggesting that statins induce geranylgeranylated Rho inactivation through a mevalonate-dependent pathway. We also found that statins inhibited the expressions of phosphorylated STA6 and NF-κB-p50 in TSLP-stimulated DCs. This study identified a specific ability of statins to control DC-mediated Th2 responses, suggesting their therapeutic potential for treating allergic diseases.

SPARC Is a New Myeloid-Derived Suppressor Cell Marker Licensing Suppressive Activities.

Myeloid-derived suppressor cells (MDSC) are well-known key negative regulators of the immune response during tumor growth, however scattered is the knowledge of their capacity to influence and adapt to the different tumor microenvironments and of the markers that identify those capacities. Here we show that the secreted protein acidic and rich in cysteine (SPARC) identifies in both human and mouse MDSC with immune suppressive capacity and pro-tumoral activities including the induction of epithelial-to-mesenchymal transition (EMT) and angiogenesis. In mice the genetic deletion of SPARC reduced MDSC immune suppression and reverted EMT. Sparc-/- MDSC were less suppressive overall and the granulocytic fraction was more prone to extrude neutrophil extracellular traps (NET). Surprisingly, arginase-I and NOS2, whose expression can be controlled by STAT3, were not down-regulated in Sparc-/- MDSC, although less suppressive than wild type (WT) counterpart. Flow cytometry analysis showed equal phosphorylation of STAT3 but reduced ROS production that was associated with reduced nuclear translocation of the NF-kB p50 subunit in Sparc-/- than WT MDSC. The limited p50 in nuclei reduce the formation of the immunosuppressive p50:p50 homodimers in favor of the p65:p50 inflammatory heterodimers. Supporting this hypothesis, the production of TNF by Sparc-/- MDSC was significantly higher than by WT MDSC. Although associated with tumor-induced chronic inflammation, TNF, if produced at high doses, becomes a key factor in mediating tumor rejection. Therefore, it is foreseeable that an unbalance in TNF production could skew MDSC toward an inflammatory, anti-tumor phenotype. Notably, TNF is also required for inflammation-driven NETosis. The high level of TNF in Sparc-/- MDSC might explain their increased spontaneous NET formation as that we detected both in vitro and in vivo, in association with signs of endothelial damage. We propose SPARC as a new potential marker of MDSC, in both human and mouse, with the additional feature of controlling MDSC suppressive activity while preventing an excessive inflammatory state through the control of NF-kB signaling pathway.

HVEM network signaling in cancer.

Somatic mutations in cancer cells may influence tumor growth, survival, or immune interactions in their microenvironment. The tumor necrosis factor receptor family member HVEM (TNFRSF14) is frequently mutated in cancers and has been attributed a tumor suppressive role in some cancer contexts. HVEM functions both as a ligand for the lymphocyte checkpoint proteins BTLA and CD160, and as a receptor that activates NF-κB signaling pathways in response to BTLA and CD160 and the TNF ligands LIGHT and LTα. BTLA functions to inhibit lymphocyte activation, but has also been ascribed a role in stimulating cell survival. CD160 functions to co-stimulate lymphocyte function, but has also been shown to activate inhibitory signaling in CD4+ T cells. Thus, the role of HVEM within diverse cancers and in regulating the immune responses to these tumors is likely context specific. Additionally, development of therapeutics that target proteins within this network of interacting proteins will require a deeper understanding of how these proteins function in a cancer-specific manner. However, the prominent role of the HVEM network in anti-cancer immune responses indicates a promising area for drug development.

New DiaP277 analogue shifts DCs to tolerogenic, and modulates NF-Kß1 to suppress autoreactive T lymphocytes in the type 1 diabetic mice.

Therapeutic efficacy of P277 against type 1 diabetes was extensively investigated and clinically evidenced. Clinical trials Phases I and II concluded promising results, while the data of P277 immunogenicity in Phase III trials represented weak responses that led to abolish medical use. But, a therapeutic performance of P277 cannot be forgotten. So, in order to exploit its therapeutic benefits and improve its immunogenicity, we developed a new analogue VP to optimize therapeutic efficacy and enhancing immunosuppressive modulations. However, new analogue was purified, and then used to immunize diabetic NOD mice to investigate antidiabetic effects through modulation of immunological status. So, DCs immune responses, relative TLRs, MyD88, and NF-Kß1 mRNA expression on DCs and splenocytes under VP effect were tested. Circulating and intracellular cytokines were also evaluated at treated and non-treated mice. Splenic T lymphocytes proliferation (Th1 and Treg cells) were also determined. Results revealed that VP significantly down regulates DCs maturation through TLR2, TLR4, and MyD88 pathways. It also shifts DCs to a tolerogenic polarization through NF-Kß1 pathway that mediates Th1 immunosuppression and enhances iTreg expanding in type1diabetes mice. Meanwhile, we noticed that VP significantly enhances iTreg CD25 + FoxP3+ proliferation. In conclusion, VP showed promising immune potential to modulate immune regulatory responses and shifts DCs to suppress autoreactive Th1 cells which ameliorated immunosuppressive potency in the type1 diabetic mice.

Immunotolerant p50/NFκB Signaling and Attenuated Hepatic IFNß Expression Increases Neonatal Sensitivity to Endotoxemia.

Sepsis is a major cause of neonatal morbidity and mortality. The current paradigm suggests that neonatal susceptibility to infection is explained by an innate immune response that is functionally immature. Recent studies in adults have questioned a therapeutic role for IFNß in sepsis; however, the role of IFNß in mediating neonatal sensitivity to sepsis is unknown. We evaluated the transcriptional regulation and expression of IFNß in early neonatal (P0) and adult murine models of endotoxemia (IP LPS, 5 mg/kg). We found that hepatic, pulmonary, and serum IFNß expression was significantly attenuated in endotoxemic neonates when compared to similarly exposed adults. Furthermore, endotoxemia induced hepatic p65/NFκB and IRF3 activation exclusively in adults. In contrast, endotoxemia induced immunotolerant p50/NFκB signaling in neonatal mice without evidence of IRF3 activation. Consistent with impaired IFNß expression and attenuated circulating serum levels, neonatal pulmonary STAT1 signaling and target gene expression was significantly lower than adult levels. Using multiple in vivo approaches, the source of hepatic IFNß expression in endotoxemic adult mice was determined to be the hepatic macrophage, and experiments in RAW 264.7 cells confirmed that LPS-induced IFNß expression was NFκB dependent. Finally, treating neonatal mice with IFNß 2 h after endotoxemia stimulated pulmonary STAT1 signaling and STAT1 dependent gene expression. Furthermore, IFNß treatment of endotoxemic neonatal animals resulted in significantly improved survival following exposure to lethal endotoxemia. In conclusion, endotoxemia induced IFNß expression is attenuated in the early neonatal period, secondary to impaired NFκB-p65/IRF3 signaling. Pre-treatment with IFNß decreases neonatal sensitivity to endotoxemia. These results support further study of the role of impaired IFNß expression and neonatal sensitivity to sepsis.

Advances and highlights in primary immunodeficiencies in 2017.

This manuscript reviews selected topics in primary immunodeficiency diseases (PIDDs) published in 2017. These include (1) the role of follicular T cells in the differentiation of B cells and development of optimal antibody responses; (2) impaired nuclear factor κB subunit 1 signaling in the pathogenesis of common variable immunodeficiency, revealing an association between impaired B-cell maturation and development of inflammatory conditions; (3) autoimmune and inflammatory manifestations in patients with PIDDs in T- and B-cell deficiencies, as well as in neutrophil disorders; (4) newly described gene defects causing PIDDs, including exostosin-like 3 (EXTL3), TNF-α-induced protein 3 (TNFAIP3 [A20]), actin-related protein 2/3 complex-subunit 1B (ARPC1B), v-Rel avian reticuloendotheliosis viral oncogene homolog A (RELA), hypoxia upregulated 1 (HYOU1), BTB domain and CNC homolog 2 (BACH2), CD70, and CD55; (5) use of rapamycin and the phosphoinositide 3-kinase inhibitor leniolisib to reduce autoimmunity and regulate B-cell function in the activated phosphoinositide 3-kinase δ syndrome; (6) improved outcomes in hematopoietic stem cell transplantation for severe combined immunodeficiency (SCID) in the last decade, with an overall 2-year survival of 90% in part caused by early diagnosis through implementation of universal newborn screening; (7) demonstration of the efficacy of lentiviral vector-mediated gene therapy for patients with adenosine deaminase-deficient SCID; (8) the promise of gene editing for PIDDs using CRISPR/Cas9 and zinc finger nuclease technology for SCID and chronic granulomatous disease; and (9) the efficacy of thymus transplantation in Europe, although associated with an unexpected high incidence of autoimmunity. The remarkable progress in the understanding and management of PIDDs reflects the current interest in this area and continues to improve the care of immunodeficient patients.

Soluble Aß1-42 suppresses TNF-α and activates NLRP3 inflammasome in THP-1 macrophages.

Deposition of amyloid-ß in Alzheimer's disease is accompanied by chronic inflammation, which involves raised levels of pro-inflammatory cytokines TNF-α, IL-6 and IL-1ß. However, the role of Aß1-42 in the inflammatory process, before it gets deposited into aggregates has not been investigated thoroughly. Through this study, we are illustrating the dual role of soluble Aß1-42 (sAß1-42) in activating the NLRP3 inflammasome and simultaneously inhibiting TNF-α secretion. Our data suggested that the treatment of chronically induced THP-1 macrophages and N9 microglial cells with sAß1-42 can suppress the major inflammatory cytokine TNF-α without affecting the level of IL-6. However, the activation of NLRP3 inflammasome was well evidenced by secretion of IL-1ß, increased expression of NLRP3 and caspase-1, implicating sAß1-42 in enhancing and suppressing one or other type of inflammation. Further investigation revealed that sAß1-42 was able to severely abrogate the expression of NF-κB, p50 and restricting the translocation of NF-κB, p65 to nucleus by inhibiting phosphorylation of IκB-α in THP-1 macrophages. These data indicate that the sAß1-42 may play a dual role during inflammatory process, wherein, it may be involved in protecting the cells from inflammatory damage due to TNF-α. This ability of sAß1-42 might be playing some role in protecting the brain cells during the process of aging and Alzheimer's disease, where, chronic inflammatory environment plays a vital role.

NFKB1 mediates Th1/Th17 activation in the pathogenesis of psoriasis.

This study was aimed to investigate whether NFKB1 participates in the pathogenesis of psoriasis by mediating Th1/Th17 cells. In this study, expression of NFKB1 was assessed in skin tissues from psoriasis patients and the healthy controls through Western blot and Immunohistochemistry. Enzyme-linked immunosorbent assay (ELISA) was used to analyze the serum levels of IFN-γ, IL-17 (IL-17A) and IL-17RA. The imiquimod-induced psoriasis mouse model was employed to examine the role of NFKB1 in psoriasis via the assessment of psoriasis area and severity index (PASI), including erythema, thickness and scales. The effects of NFKB1 on Th1/Th17 cells in were examined by flow cytometry. In vitro co-culture of Th1/Th17 cells isolated from different mice with HaCat cells was conducted to elucidate the effect of Th1/Th17 cells-mediated by NFKB1 on HaCat cells by MTT, wound healing and transwell invasion assay, respectively. The results showed that NF-κB p105/p50 expression in skin tissues was significantly increased in psoriasis (n = 21) compared to the healthy controls (n = 16), as well as levels of serum INF-γ and IL-17. Additionally, NF-κB p105/p50 expression in lesional skin tissues was much higher than that in non-lesional skin tissues of the same patients. In the psoriasis mouse model, NFKB1 overexpression significantly elevated the scores of erythema, thickness and scales. Besides, NFKB1 up-regulated the level of NF-κB p105/p50, INF-γ, T-bet, IL-17 and RORγt, as well as Th1/Th17 cells in skin tissues of psoriasis mice. Finally, in vitro assay confirmed that the activation of Th1 and Th17 mediated by NFKB1 in psoriasis promoted the proliferation, migration and invasion of keratinocytes. These findings suggest a critical role for NFKB1 in the regulation of Th1 and Th17 in psoriasis.

Cooperation of Rel family members in regulating Aß1-40-mediated pro-inflammatory cytokine secretion by retinal pigment epithelial cells.

Amyloid-beta (Aß) is a hallmark component of age-related macular degeneration (AMD), which induces secretion of pro-inflammatory cytokines from retinal pigment epithelium (RPE). Previous studies have shown that p50/RelA (p65), a member of NF-κB family, is an essential pro-inflammatory transcription factor responding to Aß1-40 stimulation, but few focused on the other two Rel transcription factor members - RelB and c-Rel - and their role in Aß1-40-mediated inflammation. It was reported that RelA, RelB and c-Rel are also implicated in various NF-κB-mediated inflammatory diseases. Therefore, we infer that Aß1-40-mediated inflammation targets not only the classical inflammation regulator, RelA, but also RelB and c-Rel. In this study, we demonstrate that intravitreally injected Aß1-40 mice develop AMD-like pathologic changes, coupled with Rel protein (RelA, RelB and c-Rel) synthesis and nuclear translocation. To focus on the interaction mechanism of Rel proteins, we found that RelB and c-Rel formed a heterodimer with RelA in mice model. We also found that c-Rel silencing decreased the levels of Aß1-40-dependent RelA expression, indicating that RelB and c-Rel may interact with RelA as coactivator and c-Rel is required to activate the expression of RelA. Moreover, Rel protein silencing decreased the expression of distinct pro-inflammatory cytokines. Together, we demonstrate that besides RelA, RelB and c-Rel can also be activated by Aß1-40, all of which mediate pro-inflammatory cytokine transcription and RPE damage. Our findings imply that RPE-mediated inflammation under the stimulation of Aß1-40 is multi-targeted and RelA, RelB and c-Rel proteins may be the new targets of anti-inflammatory agents.

Molecular impact of selective NFKB1 and NFKB2 signaling on DLBCL phenotype.

Diffuse large B-cell lymphoma (DLBCL) has been categorized into two molecular subtypes that have prognostic significance, namely germinal center B-cell like (GCB) and activated B-cell like (ABC). Although ABC-DLBCL has been associated with NF-κB activation, the relationships between activation of specific NF-κB signals and DLBCL phenotype remain unclear. Application of novel gene expression classifiers identified two new DLBCL categories characterized by selective p100 (NF-κB2) and p105 (NF-κB1) signaling. Interestingly, our molecular studies showed that p105 signaling is predominantly associated with GCB subtype and histone mutations. Conversely, most tumors with p100 signaling displayed ABC phenotype and harbored ABC-associated mutations in genes such as MYD88 and PIM1. In vitro, MYD88 L265P mutation promoted p100 signaling through TAK1/IKKα and GSK3/Fbxw7a pathways, suggesting a novel role for this protein as an upstream regulator of p100. p100 signaling was engaged during activation of normal B cells, suggesting p100's role in ABC phenotype development. Additionally, silencing p100 in ABC-DLBCL cells resulted in a GCB-like phenotype, with suppression of Blimp, IRF4 and XBP1 and upregulation of BCL6, whereas introduction of p52 or p100 into GC cells resulted in differentiation toward an ABC-like phenotype. Together, these findings identify specific roles for p100 and p105 signaling in defining DLBCL molecular subtypes and posit MYD88/p100 signaling as a regulator for B-cell activation.