Explore the vast range of titles available.

ObjectivesT follicular helper (Tfh) cells are critical in the development and progression of systemic lupus erythematosus (SLE). To assess the characteristics and mechanisms of differentiation of Tfh cells, we investigated the phenotype of T helper cells in patients with SLE and underlying epigenetic modifications by cytokine-induced signal transducer and activators of transcription (STAT) family factors.MethodsPeripheral blood mononuclear cells from patients and healthy donors were analysed by flow cytometry. CD4+ T cells were isolated and cultured under various stimulations. Expression of characteristic markers and phosphorylation of STATs were analysed by flow cytometry and quantitative PCR. Histone modifications were analysed by chromatin immunoprecipitation (ChIP)-PCR.ResultsDifferentiation of CD4+CXCR5+CXCR3+Bcl-6+T-bet+IL-21+IFN-γ+Tfh-Th1-like cells was induced by interleukin (IL)-12-induced activation of STAT1 and STAT4 simultaneously. The loci of Bcl-6 and T-bet at STAT binding sites were marked by bivalent histone modifications. After IL-12 stimulation, both STAT1 and STAT4 directly bound on BCL6 and TBX21 gene loci accompanied by suppression of repressive histone mark trimethylated histone 3 lysine 27. Levels of serum IL-12 and interferon (IFN)-γ, expression of IL-12 receptors and proportion of CXCR5+CXCR3+ activated Tfh-Th1-like cells were increased in patients with SLE. Furthermore, the level of pSTAT1, pSTAT4 and T-bet were higher in activated Tfh-Th1-like cells than non-Tfh-Th1 cells.ConclusionOur findings suggest that IL-12-mediated co-activation of STAT1 and STAT4 alters histone modification, resulting in differentiation of Tfh-Th1-like cells that are characteristically expanded in patients with SLE. This could be one of the underlying mechanisms responsible for expansion of Tfh-Th1-like cells and potentially helpful towards development of cell-specific treatment for SLE.

Stromal interaction molecule 1 (STIM1) is critical for store-operated Ca 2+ entry (SOCE) and T cell activation. T helper 1 (T H 1) cells, which express T-bet (encoded by TBX21 ), mediate immunity to intracellular pathogens. Although SOCE is known to regulate other T H lineages, its role in Th1 differentiation remains unclear. Here, we report a patient with an intronic loss-of-function mutation in STIM1 , which abolishes SOCE and causes immunodeficiency. We demonstrate that SOCE promotes nuclear factor of activated T cells (NFAT) binding to conserved noncoding sequence (CNS)-12 in the TBX21 enhancer and enables NFAT to synergize with STAT1 to mediate TBX21 expression. While SOCE-deficient CD4 + T cells have reduced expression of TBX21 in the absence of interleukin-12 (IL-12), their expression of IL-12 receptors β1 and β2 is increased, sensitizing them to IL-12 signaling and allowing IL-12 to rescue T-bet expression. Our study reveals that the STIM1-SOCE–NFAT signaling axis is essential for the differentiation of Th1 cells depending on the cytokine milieu. Feske and colleagues show how STIM- and ORAI-dependent calcium activation of NFAT plus IFN–STAT1 signaling activates T-bet expression independently of IL-12 stimulation. This NFAT–STAT1 activation pathway is required for T H 1 cell differentiation and protection against viral infections when IL-12 is missing.

In calcium electroporation (CaEP), electroporation enables the cellular uptake of supraphysiological concentrations of Ca , causing the induction of cell death. The effectiveness of CaEP has already been evaluated in clinical trials; however, confirmatory preclinical studies are still needed to further elucidate its effectiveness and underlying mechanisms. Here, we tested and compared its efficiency on two different tumor models to electrochemotherapy (ECT) and in combination with gene electrotransfer (GET) of a plasmid encoding interleukin-12 (IL-12). We hypothesized that IL-12 potentiates the antitumor effect of local ablative therapies as CaEP and ECT. The effect of CaEP was tested as well as in murine melanoma B16-F10 and murine mammary carcinoma 4T1 in comparison to ECT with bleomycin. Specifically, the treatment efficacy of CaEP with increasing calcium concentrations alone or in combination with IL-12 GET in different treatment protocols was investigated. We closely examined the tumor microenvironment by immunofluorescence staining of immune cells, as well as blood vessels and proliferating cells. , CaEP and ECT with bleomycin reduced cell viability in a dose-dependent manner. We observed no differences in sensitivity between the two cell lines. A dose-dependent response was also observed ; however, the efficacy was better in 4T1 tumors than in B16-F10 tumors. In 4T1 tumors, CaEP with 250 mM Ca resulted in more than 30 days of growth delay, which was comparable to ECT with bleomycin. In contrast, adjuvant peritumoral application of IL-12 GET after CaEP prolonged the survival of B16-F10, but not 4T1-bearing mice. Moreover, CaEP with peritumoral IL-12 GET modified tumor immune cell populations and tumor vasculature. Mice bearing 4T1 tumors responded better to CaEP than mice bearing B16-F10 tumors, even though a similar response was observed . Namely, one of the most important factors might be involvement of the immune system. This was confirmed by the combination of CaEP or ECT with IL-12 GET, which further enhanced antitumor effectiveness. However, the potentiation of CaEP effectiveness was also highly dependent on tumor type; it was more pronounced in poorly immunogenic B16-F10 tumors compared to moderately immunogenic 4T1 tumors.

We recently reported the genetic cause of autosomal dominant chronic mucocutaneous candidiasis (AD-CMC) as a mutation in the STAT1 gene. In the present study we show that STAT1 Arg274Trp mutations in the coiled-coil (CC) domain is the genetic cause of AD-CMC in three families of patients. Cloning and transfection experiments demonstrate that mutated STAT1 inhibits IL12R/IL-23R signaling, with hyperphosphorylation of STAT1 as the likely underlying molecular mechanism. Inhibition of signaling through the receptors for IL-12 and IL-23 leads to strongly diminished Th1/Th17 responses and hence to increased susceptibility to fungal infections. The challenge for the future is to translate this knowledge into novel strategies for the treatment of this severe immunodeficiency.

Members of the interleukin 12 (IL-12) family have been known to be inflammatory factors since their discovery. The IL-12 family consists of IL-12, IL-23, IL-27, IL-35, and a new member, IL-39, which has recently been identified and has not yet been studied extensively. Current literature has described the mechanisms of immunity of these cytokines and potential uses for therapy and medical cures. IL-12 was found first and is effective in combatting a wide range of naturally occurring viral infections through the upregulation of various cytokines to clear the infected cells. IL-23 has an essential function in immune networks, can induce IL-17 production, and can antagonize inhibition from IL-12 in the presence of T helper (Th) 17 cells, resulting in type II IFN (IFN-γ) regulation. IL-27 has a competitive relationship to IL-35 because they both include the same subunit, the Epstein–Barr virus-induced gene3 (EBi3). This review provides a simple introduction to the IL-12 family and focuses on their functions relevant to their actions to counteract viral infections.

Objective: Trained immunity of natural killer (NK) cells has shown great potential in the treatment of cancers by eliciting enhancedeffector responses to restimulation by cytokines or cancer cells for long time periods after preactivation. However, the human NKcells responsible for the generation and maintenance of trained immunity are largely unknown. We hypothesized that heterogeneoushuman NK cells would respond differentially to stimulation with a combination of IL-12, IL-15, and IL-18, and that an NK cell subsetmight exist that is mainly responsible for the induction of trained immunity. On the basis of our hypothesis, we aimed to identify thesubset from which cytokine-trained human NK cells originate and to explore possible regulatory targets for drug intervention. Methods: Flow cytometry assays were performed to analyze the functions of cytokine-trained NK cells and examine cell divisionand protein expression in NK cell subsets. Single-cell RNA sequencing (scRNA-seq) plus TotalSeq™ technology was used to track theheterogeneity of NK cells during the induction of trained immunity. Results: Traditional developmental markers for peripheral NK cells were unable to identify the precursors of human NK cells withtrained immunity. Therefore, we used scRNA-seq plus TotalSeq™ technology to track the heterogeneity of NK cells during theinduction of trained immunity and identified a unique cluster of CD57−NKG2A+EZH2+IFNG+MKI67+IL12R+IL15R+IL18R+ NKcells. Enrichment and pseudotime trajectory analyses suggested that this cluster of NK cells contained the precursor of trainedNK cells. We then used flow cytometry to further investigate the role of EZH2 in trained NK precursors and found that CD57−NKG2A+EZH2+ NK cells had faster cell cycles and an enhanced trained phenotype, and EZH2 inhibition significantly impaired theinduction of trained immunity in NK cells. These results suggested that EZH2 is a unique epigenetic marker of precursors of humanNK cells with trained immunity. Conclusions: Our work revealed human NK heterogeneity in the induction of trained immunity, identified the precursor subset fortrained NK cells, and demonstrated the critical role of EZH2 in the induction of trained immunity in human NK cells.

Chronic inflammatory diseases like inflammatory bowel diseases (IBD) or psoriasis represents a worldwide health burden. Researchers provided great achievements in understanding the origin of these diseases leading to improved therapeutic options. The discovery of cytokines like tumor necrosis factor-[alpha] or transforming growth factor-[beta] are examples for these efforts. Interleukin 12 (IL 12) and interleukin 23 (IL 23) represent different important cytokines in this regard. They both belong to the interleukin 12 family and are related by sharing the subunit p40. Ustekinumab is an antibody that blocks p40 and thereby interleukins 12 and 23. Trials showed promising results in treating IBD patients with this drug. Consequently, new questions arose about the distinct features of IL 12 and 23. This review focuses on these interleukins regarding their functions in the healthy and inflamed gut and provides an overview about the results from in vitro and in vivo studies as well as clinical trials. Keywords: inflammatory bowel diseases, Crohn's disease, ulcerative colitis, interleukin 12, interleukin 23

The rate of caesarean section delivery (CSD) is increasing worldwide. It remains unclear whether disruption of mother-to-neonate transmission of microbiota through CSD occurs and whether it affects human physiology. Here we perform metagenomic analysis of earliest gut microbial community structures and functions. We identify differences in encoded functions between microbiomes of vaginally delivered (VD) and CSD neonates. Several functional pathways are over-represented in VD neonates, including lipopolysaccharide (LPS) biosynthesis. We link these enriched functions to individual-specific strains, which are transmitted from mothers to neonates in case of VD. The stimulation of primary human immune cells with LPS isolated from early stool samples of VD neonates results in higher levels of tumour necrosis factor (TNF-α) and interleukin 18 (IL-18). Accordingly, the observed levels of TNF-α and IL-18 in neonatal blood plasma are higher after VD. Taken together, our results support that CSD disrupts mother-to-neonate transmission of specific microbial strains, linked functional repertoires and immune-stimulatory potential during a critical window for neonatal immune system priming. The effects of caesarean section delivery on mother-to-neonate transmission of microbiota are unclear. Here the authors show that caesarean section delivery can affect the transmission of specific microbial strains and the immunomodulatory potential of the microbiota.

PurposeMendelian susceptibility to mycobacterial disease (MSMD) is a rare primary immunodeficiency, triggered by non-tuberculous mycobacteria or Bacillus Calmette-Guérin (BCG) vaccines and characterized by severe diseases. All known genetic etiologies are inborn errors of IFN-γ-mediated immunity. Here, we report the molecular, cellular, and clinical features of patients from 15 Iranian families with disseminated disease without vaccination (2 patients) or following live BCG vaccination (14 patients).MethodsWe used whole blood samples from 16 patients and 12 age-matched healthy controls. To measure IL-12 and IFN-γ, samples were activated by BCG plus recombinant human IFN-γ or recombinant human IL-12. Immunological assessments and genetic analysis were also done for the patients.ResultsEight patients affected as a result of parental first-cousin marriages. Seven patients originated from multiplex kindred with positive history of death because of tuberculosis or finding the MSMD-related gene mutations. Two patients died due to mycobacterial disease at the ages of 8 months and 3.7 years. The remaining patients were alive at the last follow-up and were aged between 2 and 13 years. Patients suffered from infections including chronic mucocutaneous candidiasis (n = 10), salmonellosis (n = 2), and Leishmania (responsible for visceral form) (n = 2). Thirteen patients presented with autosomal recessive (AR) IL-12Rβ1 deficiency, meaning their cells produced low levels of IFN-γ. Bi-allelic IL12RB1 mutations were detected in nine of patients. Three patients with AR IL-12p40 deficiency (bi-allelic IL12B mutations) produced low levels of both IL-12 and IFN-γ. Overall, we found five mutations in the IL12RB1 gene and three mutations in the IL12B gene. Except one mutation in exon 5 (c.510C>A) of IL12B, all others were previously reported to be loss-of-function mutations.ConclusionsWe found low levels of IFN-γ production and failure to respond to IL12 in 13 Iranian MSMD patients. Due to complicated clinical manifestations in affected children, early cellular and molecular diagnostics is crucial in susceptible patients.

Human African Trypanosomiasis (HAT) or sleeping sickness is a Neglected Tropical Disease. Long regarded as an invariably fatal disease, there is increasing evidence that infection by T. b. gambiense can result in a wide range of clinical outcomes, including latent infections, which are long lasting infections with no parasites detectable by microscopy. The determinants of this clinical diversity are not well understood but could be due in part to parasite or host genetic diversity in multiple genes, or their interactions. A candidate gene association study was conducted in Côte d'Ivoire using a case-control design which included a total of 233 subjects (100 active HAT cases, 100 controls and 33 latent infections). All three possible pairwise comparisons between the three phenotypes were tested using 96 SNPs in16 candidate genes (IL1, IL4, IL4R, IL6, IL8, IL10, IL12, IL12R, TNFA, INFG, MIF, APOL1, HPR, CFH, HLA-A and HLA-G). Data from 77 SNPs passed quality control. There were suggestive associations at three loci in IL6 and TNFA in the comparison between active cases and controls, one SNP in each of APOL1, MIF and IL6 in the comparison between latent infections and active cases and seven SNP in IL4, HLA-G and TNFA between latent infections and controls. No associations remained significant after Bonferroni correction, but the Benjamini Hochberg false discovery rate test indicated that there were strong probabilities that at least some of the associations were genuine. The excess of associations with latent infections despite the small number of samples available suggests that these subjects form a distinct genetic cluster different from active HAT cases and controls, although no clustering by phenotype was observed by principle component analysis. This underlines the complexity of the interactions existing between host genetic polymorphisms and parasite diversity.