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Infection and Immunity Sep 2023is a causative agent of cutaneous ulcers in children who live in the tropics and of the genital ulcer disease chancroid in sexually active persons. In the anaerobic...
is a causative agent of cutaneous ulcers in children who live in the tropics and of the genital ulcer disease chancroid in sexually active persons. In the anaerobic environment of abscesses and ulcers, anaerobic respiration and mixed acid fermentation (MAF) can be used to provide cellular energy. In , MAF produces formate, acetate, lactate, succinate, and ethanol; however, MAF has not been studied in . In human challenge experiments with 35000HP, transcripts of the formate transporter FocA and pyruvate formate lyase (PflB) were upregulated in pustules compared to the inocula. We made single and double mutants of and in 35000HP. Growth of 35000HPΔ was similar to 35000HP, but 35000HPΔ and 35000HPΔ had growth defects during both aerobic and anaerobic growth. Mutants lacking did not secrete formate into the media. However, formate was secreted into the media by 35000HPΔ, indicating that has alternative formate transporters. The pH of the media during anaerobic growth decreased for 35000HP and 35000HPΔ, but not for 35000HPΔ or 35000HPΔ, indicating that is the main contributor to media acidification during anaerobic growth. We tested whether formate production and transport were required for virulence in seven human volunteers in a mutant versus parent trial between 35000HPΔ and 35000HP. The pustule formation rate was similar for 35000HP (42.9%)- and 35000HPΔ (62%)-inoculated sites. Although formate production occurs during growth and transcripts are upregulated during human infection, and are not required for virulence in humans.
Topics: Child; Humans; Haemophilus ducreyi; Virulence; Ulcer; Healthy Volunteers; Formates; Escherichia coli; Membrane Transport Proteins; Escherichia coli Proteins
PubMed: 37594273
DOI: 10.1128/iai.00176-23 -
Human Genetics Sep 2023Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a condition caused by mutations in NOTCH3 and results in a...
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a condition caused by mutations in NOTCH3 and results in a phenotype characterised by recurrent strokes, vascular dementia and migraines. Whilst a genetic basis for the disease is known, the molecular mechanisms underpinning the pathology of CADASIL are still yet to be determined. Studies conducted at the Genomics Research Centre (GRC) have also identified that only 15-23% of individuals clinically suspected of CADASIL have mutations in NOTCH3. Based on this, whole exome sequencing was used to identify novel genetic variants for CADASIL-like cerebral small-vessel disease (CSVD). Analysis of functionally important variants in 50 individuals was investigated using overrepresentation tests in Gene ontology software to identify biological processes that are potentially affected in this group of patients. Further investigation of the genes in these processes was completed using the TRAPD software to identify if there is an increased number (burden) of mutations that are associated with CADASIL-like pathology. Results from this study identified that cell-cell adhesion genes were positively overrepresented in the PANTHER GO-slim database. TRAPD burden testing identified n = 15 genes that had a higher number of rare (MAF < 0.001) and predicted functionally relevant (SIFT < 0.05, PolyPhen > 0.8) mutations compared to the gnomAD v2.1.1 exome control dataset. Furthermore, these results identified ARVCF, GPR17, PTPRS, and CELSR1 as novel candidate genes in CADASIL-related pathology. This study identified a novel process that may be playing a role in the vascular damage related to CADASIL-related CSVD and implicated n = 15 genes in playing a role in the disease.
Topics: Humans; CADASIL; Cell Adhesion; Mutation; Exons; Phenotype; Magnetic Resonance Imaging; Receptors, G-Protein-Coupled
PubMed: 37422595
DOI: 10.1007/s00439-023-02584-8 -
Journal of Translational Medicine Oct 2023Triple-negative breast cancer (TNBC) development may be associated with tumor immune escape. This study explores whether the CHI3L1/MAF/CTLA4/S100A4 axis affects immune...
BACKGROUND
Triple-negative breast cancer (TNBC) development may be associated with tumor immune escape. This study explores whether the CHI3L1/MAF/CTLA4/S100A4 axis affects immune escape in TNBC through interplay with triple-negative breast cancer stem cells (TN-BCSCs).
OBJECTIVE
The aim of this study is to utilize single-cell transcriptome sequencing (scRNA-seq) to uncover the molecular mechanisms by which the CHI3L1/MAF/CTLA4 signaling pathway may mediate immune evasion in triple-negative breast cancer through the interaction between tumor stem cells (CSCs) and immune cells.
METHODS
Cell subsets in TNBC tissues were obtained through scRNA-seq, followed by screening differentially expressed genes in TN-BCSCs and B.C.s (CD44 and CD24) and predicting the transcription factor regulated by CHI3L1. Effect of CHI3L1 on the stemness phenotype of TNBC cells investigated. Effects of BCSCs-231-derived CHI3L1 on CTLA4 expression in T cells were explored after co-culture of BCSCs-231 cells obtained from microsphere culture of TN-BCSCs with T cells. BCSCs-231-treated T cells were co-cultured with CD8 T cells to explore the resultant effect on T cell cytotoxicity. An orthotopic B.C. transplanted tumor model in mice with humanized immune systems was constructed, in which the Role of CHI3L1/MAF/CTLA4 in the immune escape of TNBC was explored.
RESULTS
Eight cell subsets were found in the TNBC tissues, and the existence of TN-BCSCs was observed in the epithelial cell subset. CHI3L1 was related to the stemness phenotype of TNBC cells. TN-BCSC-derived CHI3L1 increased CTLA4 expression in T cells through MAF, inhibiting CD8 T cell cytotoxicity and inducing immunosuppression. Furthermore, the CTLA4 T cells might secrete S100A4 to promote the stemness phenotype of TNBC cells.
CONCLUSIONS
TN-BCSC-derived CHI3L1 upregulates CTLA4 expression in T cells through MAF, suppressing the function of CD8 T cells, which promotes the immune escape of TNBC.
Topics: Humans; Animals; Mice; Triple Negative Breast Neoplasms; CTLA-4 Antigen; CD8-Positive T-Lymphocytes; Signal Transduction; Neoplastic Stem Cells; Cell Line, Tumor; Chitinase-3-Like Protein 1
PubMed: 37838657
DOI: 10.1186/s12967-023-04532-6 -
Cell Death & Disease Nov 2023The transcription factor MYB plays a pivotal role in haematopoietic homoeostasis and its aberrant expression is involved in the genesis and maintenance of acute myeloid...
The transcription factor MYB plays a pivotal role in haematopoietic homoeostasis and its aberrant expression is involved in the genesis and maintenance of acute myeloid leukaemia (AML). We have previously demonstrated that not all AML subtypes display the same dependency on MYB expression and that such variability is dictated by the nature of the driver mutation. However, whether this difference in MYB dependency is a general trend in AML remains to be further elucidated. Here, we investigate the role of MYB in human leukaemia by performing siRNA-mediated knock-down in cell line models of AML with different driver lesions. We show that the characteristic reduction in proliferation and the concomitant induction of myeloid differentiation that is observed in MLL-rearranged and t(8;21) leukaemias upon MYB suppression is not seen in AML cells with a complex karyotype. Transcriptome analyses revealed that MYB ablation produces consensual increase of MAFB expression in MYB-dependent cells and, interestingly, the ectopic expression of MAFB could phenocopy the effect of MYB suppression. Accordingly, in silico stratification analyses of molecular data from AML patients revealed a reciprocal relationship between MYB and MAFB expression, highlighting a novel biological interconnection between these two factors in AML and supporting new rationales of MAFB targeting in MLL-rearranged leukaemias.
Topics: Humans; Cell Line; Leukemia, Myeloid, Acute; MafB Transcription Factor; Myeloid-Lymphoid Leukemia Protein; Phenotype; RNA, Small Interfering
PubMed: 37996430
DOI: 10.1038/s41419-023-06276-z -
Cell Reports Oct 2023T cell receptor (TCR) Vγ4-expressing γδ T cells comprise interferon γ (IFNγ)- and interleukin-17 (IL-17)-producing effector subsets, with a preference for IL-17...
T cell receptor (TCR) Vγ4-expressing γδ T cells comprise interferon γ (IFNγ)- and interleukin-17 (IL-17)-producing effector subsets, with a preference for IL-17 effector fate decisions during early ontogeny. The existence of adult-thymus-derived IL-17 T cells (γδ17) remains controversial. Here, we use a mouse model in which T cells are generated exclusively in the adult thymus and employ single-cell chromatin state analysis to study their development. We identify adult-thymus-derived Vγ4 T cells that have all the molecular programs to become IL-17 producers. However, they have reduced IL-17 production capabilities and rarely reach the periphery. Moreover, this study provides high-resolution profiles of Vγ4 T cells in the adult thymus and lymph nodes and identifies Zeb1 as a potential γδ17 cell regulator. Together, this study provides valuable insights into the developmental traits of Vγ4 T cells during adulthood and supports the idea of age-specific signals required for thymic export and/or peripheral maturation of γδ17 cells.
Topics: Mice; Animals; Interleukin-17; Receptors, Antigen, T-Cell, gamma-delta; Nuclear Receptor Subfamily 1, Group F, Member 3; Mice, Inbred C57BL; T-Lymphocytes; Thymus Gland; T-Lymphocyte Subsets; Proto-Oncogene Proteins c-maf
PubMed: 37815917
DOI: 10.1016/j.celrep.2023.113230 -
JCI Insight Aug 2023Type 2 diabetes (T2D) is associated with compromised identity of insulin-producing pancreatic islet β cells, characterized by inappropriate production of other islet...
Type 2 diabetes (T2D) is associated with compromised identity of insulin-producing pancreatic islet β cells, characterized by inappropriate production of other islet cell-enriched hormones. Here, we examined how hormone misexpression was influenced by the MAFA and MAFB transcription factors, closely related proteins that maintain islet cell function. Mice specifically lacking MafA in β cells demonstrated broad, population-wide changes in hormone gene expression with an overall gene signature closely resembling islet gastrin+ (Gast+) cells generated under conditions of chronic hyperglycemia and obesity. A human β cell line deficient in MAFB, but not one lacking MAFA, also produced a GAST+ gene expression pattern. In addition, GAST was detected in human T2D β cells with low levels of MAFB. Moreover, evidence is provided that human MAFB can directly repress GAST gene transcription. These results support a potentially novel, species-specific role for MafA and MAFB in maintaining adult mouse and human β cell identity, respectively. Here, we discuss the possibility that induction of Gast/GAST and other non-β cell hormones, by reduction in the levels of these transcription factors, represents a dysfunctional β cell signature.
Topics: Adult; Humans; Animals; Mice; MafB Transcription Factor; Diabetes Mellitus, Type 2; Islets of Langerhans; Insulin-Secreting Cells; Insulin
PubMed: 37606041
DOI: 10.1172/jci.insight.166386 -
Food Science & Nutrition Mar 2024Studies suggest that mangiferin (MAF) has good therapeutic effects on chronic bronchitis and hepatitis. Also, it is one of the antiviral ingredients in Bunge. However,...
Studies suggest that mangiferin (MAF) has good therapeutic effects on chronic bronchitis and hepatitis. Also, it is one of the antiviral ingredients in Bunge. However, its effect on the LPS-induced inflammation and intestinal flora during sepsis remains unclear yet. In the present study, LPS-stimulated inflammation RAW264.7 cells and LPS-induced sepsis mice were used to evaluate the efficacy of MAF in vitro and in vivo. 16S rDNA sequencing was performed to analyze the characteristics of intestinal flora of the sepsis mice. It has been demonstrated that MAF (12.5 and 25 μg/mL) significantly inhibited protein expressions of TLR4, MyD88, NF-κB, and TNF-α in the LPS-treated cells and reduced the supernatant TNF-α and IL-6 levels. In vivo, MAF (20 mg/kg) markedly protected the sepsis mice and reduced the serum TNF-α and IL-6 levels. Also, MAF significantly downregulated the protein expressions of TLR4, NF-κB, and MyD88 in the livers. Importantly, MAF significantly attenuated the pathological injuries of the livers and small intestines. Further, MAF significantly increased proportion of and decreased the proportions of , , , and at phylum level, and it markedly reduced the proportions of , , at genus level. Moreover, MAF affects some metabolism-related pathways such as citrate cycle (TCA cycle), lipoic acid metabolism, oxidative phosphorylation, bacterial chemotaxis, fatty acid biosynthesis, and peptidoglycan biosynthesis of the intestinal flora. Thus, it can be concluded that MAF as a treatment reduces the inflammatory responses in vitro and in vivo by inhibiting the TLR4/ MyD88/NF-κB pathway, and corrects intestinal flora imbalance during sepsis to some degree.
PubMed: 38455195
DOI: 10.1002/fsn3.3907 -
Plants (Basel, Switzerland) Sep 2023MADS-box genes encode transcription factors that play important roles in the development and evolution of plants. There are more than a dozen clades of MADS-box genes in...
MADS-box genes encode transcription factors that play important roles in the development and evolution of plants. There are more than a dozen clades of MADS-box genes in angiosperms, of which those with functions in the specification of floral organ identity are especially well-known. From what has been elucidated in the model plant , the clade of -like MADS-box genes, comprising -like genes and -like genes, are somewhat special among the MADS-box genes of plants since -like genes, especially -like genes, show unusual evolutionary dynamics, in that they generate clusters of tandemly duplicated genes. Here, we make use of the latest genomic data of Brassicaceae to study this remarkable feature of the -like genes in a phylogenetic context. We have identified all -like genes in the genomes of 29 species of Brassicaceae and reconstructed the phylogeny of these genes employing a Maximum Likelihood method. In addition, we conducted selection analyses using PAML. Our results reveal that there are three major clades of -like genes in Brassicaceae that all evolve under purifying selection but with remarkably different strengths. We confirm that the tandem arrangement of -like genes in the genomes of Brassicaceae resulted in a high rate of duplications and losses. Interestingly, -like genes also seem to be prone to transposition. Considering the role of -like genes () in the timing of floral transition, we hypothesize that this rapid evolution of the -like genes was a main contributor to the successful adaptation of Brassicaceae to different environments.
PubMed: 37765445
DOI: 10.3390/plants12183281 -
International Journal of Molecular... Apr 2024A spectrum of immune states resulting from tumor resident macrophages and T-lymphocytes in the solid tumor microenvironment correlates with patient outcomes. We...
A spectrum of immune states resulting from tumor resident macrophages and T-lymphocytes in the solid tumor microenvironment correlates with patient outcomes. We hypothesized that in gastric cancer (GC), macrophages in a polarized immunosuppressive transcriptional state would be prognostic of poor survival. We derived transcriptomic signatures for M2 (M2, ; ; ; ; ; ; ; ; ; ) and M1 (M1, ; ; ; ; ; ; ) macrophages, and cytolytic T-lymphocytes (CTL, ; ; ; ; ). Primary GC in a TCGA stomach cancer dataset was evaluated for signature expressions, and a log-rank test determined overall survival (OS) and the disease-free interval (DFI). In 341 TCGA GC entries, high M2 expression was associated with histological types and later stages. Low M2 expression was associated with significantly better 5-year OS and DFI. We validated M2 in prospectively collected peritoneal fluid of a GC patient cohort ( = 28). Single-cell RNA sequencing was used for signature expression in cells and the log-rank test compared OS. GC patients with high M2 in cells in their peritoneal fluid had significantly worse OS than those with low expression. Multivariate analyses confirmed M2 was significantly and independently associated with survival. As an independent predictor of poor survival, M2 may be prognostic in primary tumors and peritoneal fluid of GC patients.
Topics: Humans; Stomach Neoplasms; Peritoneum; Macrophages, Peritoneal; Biomarkers; Macrophages; Tumor Microenvironment; Fibrinogen
PubMed: 38612926
DOI: 10.3390/ijms25074117 -
Arthritis Research & Therapy Oct 2023IL-37 is an anti-inflammatory cytokine involved in inflammatory and autoimmune diseases. We aimed to investigate the association between IL-37 genetic variants, IL-37...
OBJECTIVES
IL-37 is an anti-inflammatory cytokine involved in inflammatory and autoimmune diseases. We aimed to investigate the association between IL-37 genetic variants, IL-37 plasma levels, and various clinical phases of gout.
METHODS
The study included a control group with no history of primary hyperuricemia/gout, (n = 50), asymptomatic hyperuricemia (n = 74), intercritical gout (n = 200), acute gouty flare (n = 18), and chronic tophaceous gout (n = 30). Plasma IL-37 was analysed using enzyme-linked immunosorbent assay. All coding regions and intron-exon boundaries of IL-37 and exons 1-5 were amplified and sequenced.
RESULTS
Plasma levels of IL-37 were significantly higher in asymptomatic hyperuricemic (p = 0.045), intercritical gout (p = 0.001), and chronic tophaceous gout (p = 0.021) cohorts when compared to control group. The levels of IL-37 in patients with acute gouty flare were comparable to control group (p = 0.061). We identified 15 genetic variants of IL-37: eight intron (rs2708959, rs2723170, rs2708958, rs2723169 rs2466448, rs3811045, rs3811048, rs2708944) and seven non-synonymous allelic variants (rs3811046, rs3811047, rs2708943, rs2723183, rs2723187, rs2708947, rs27231927), of which rs2708959 showed an over-presentation in gouty and acute flare cohorts (p = 0.003 and 0.033, respectively) compared to European population (minor allelic frequency MAF = 0.05) but not in control and hyperuricemic cohorts (p/MAF = 0.17/0.08 and 0.71/0.05, respectively).. On the contrary, rs3811045, rs3811046, rs3811047, and rs3811048 were underrepresented among individuals with tophaceous gout (MAF = 0.57) compared to European MAF 0.70-0.71, but not compared to the control cohort (MAF = 0.67).
CONCLUSIONS
We demonstrated the up-regulation of IL-37 levels across the clinical phases of gout: asymptomatic hyperuricemia, intercritical, and chronic tophaceous gout compared to control. Moreover, 15 genetic variants of IL-37 were identified and their associations with the clinical variants of gout were evaluated.
Topics: Humans; Arthritis, Gouty; Gout; Hyperuricemia; Interleukin-1beta; Uric Acid
PubMed: 37853488
DOI: 10.1186/s13075-023-03188-3