Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 28
Filter
Add more filters

Country/Region as subject
Publication year range
1.
Int J Mol Sci ; 24(19)2023 Sep 26.
Article in English | MEDLINE | ID: mdl-37834041

ABSTRACT

Persistent high-risk human papillomavirus (HPV) infection is a pivotal factor in the progression of cervical cancer. In recent years, an increasing interest has emerged in comprehending the influence of HPV on head and neck squamous cell carcinoma (HNSCC). Notably, it is well established that HPV-associated HNSCC show cases with distinct molecular and clinical attributes compared to HPV-negative cases. The present study delves into the epigenetic landscape of HPV16, specifically its L1 gene and untranslated region (UTR), through pyrosequencing, while the HPV16 DNA physical status was evaluated using E2/E6 ratio analysis in HPV16-positive HNSCC FFPE biopsies. Our findings reveal substantial methylation across six sites within the HPV16 L1 gene and seven sites in the UTR. Specifically, methylation percentages of two L1 CpG sites (7136, 7145) exhibit significant associations with tumor histological grade (p < 0.01), while proving concurrent methylation across multiple sites. The HPV16 DNA physical status was not correlated with the methylation of viral genome or tumor characteristics. This is the first study that examines epigenetic modifications and the HPV16 DNA physical status in Greek HNSCC patients. Our findings suggest an orchestrated epigenetic modulation among specific sites, impacting viral gene expression and intricate virus-host interactions.


Subject(s)
Carcinoma, Squamous Cell , Head and Neck Neoplasms , Oncogene Proteins, Viral , Papillomavirus Infections , Female , Humans , Squamous Cell Carcinoma of Head and Neck/genetics , Squamous Cell Carcinoma of Head and Neck/complications , Human Papillomavirus Viruses , Carcinoma, Squamous Cell/pathology , DNA Methylation , Papillomavirus Infections/complications , Papillomavirus Infections/genetics , Head and Neck Neoplasms/genetics , Head and Neck Neoplasms/complications , DNA/metabolism , Oncogene Proteins, Viral/genetics , Oncogene Proteins, Viral/metabolism , DNA, Viral/genetics , DNA, Viral/metabolism
2.
Fish Shellfish Immunol ; 123: 469-478, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35354104

ABSTRACT

Even though Listeria monocytogenes is an extensive-studied foodborne pathogen, genome analysis of isolates from snails that may represent a reservoir of L. monocytogenes are still scarce. Here, we use whole-genome sequencing (WGS) to assess the genomic diversity of hypervirulent, virulent and non-virulent phenotypes of 15 L. monocytogenes isolated from snails to unveil their survival, virulence, and host-pathogen mechanisms of interactions in a snail infection model. Most of isolates (66.7%) were characterized as multidrug resistant (MDR) and belonged to clonal complexes (CCs) which are strongly associated with cases of human infection. All isolates contained intact genes associated with invasion and infection while hypervirulent isolates are adapted to host environment, possessing genes which are involved in teichoic acid biosynthesis, peptidoglycan modification and biofilm formation, correlating with their tolerance to haemolymph plasma phenotype and biofilm formation ability. A snail infection model showed that hypervirulent isolates triggered programmed host cell death pathway by increasing up to 30% the circulating apoptotic hemocytes in combination with induced nitrate production and reactive oxygen species (ROS) generation in snails' haemolymph. In contrast, the administration of the non-virulent strain which possesses a truncated mogR gene that regulates flagellar motility gene expression led only to an increase of necrotic non-apoptotic cells. Overall, this study provides significant insights into the genetic diversity of L. monocytogenes from snails, the genomic features of them linked to their hypervirulent/non-virulent phenotype, and the mechanisms of host-pathogen interactions.


Subject(s)
Listeria monocytogenes , Listeriosis , Animals , Host-Pathogen Interactions , Meat , Whole Genome Sequencing
3.
Br J Haematol ; 194(1): 158-167, 2021 07.
Article in English | MEDLINE | ID: mdl-34036576

ABSTRACT

Advances in immunotherapy with T cells armed with chimeric antigen receptors (CAR-Ts), opened up new horizons for the treatment of B-cell lymphoid malignancies. However, the lack of appropriate targetable antigens on the malignant myeloid cell deprives patients with refractory acute myeloid leukaemia of effective CAR-T therapies. Although non-engineered T cells targeting multiple leukaemia-associated antigens [i.e. leukaemia-specific T cells (Leuk-STs)] represent an alternative approach, the prerequisite challenge to obtain high numbers of dendritic cells (DCs) for large-scale Leuk-ST generation, limits their clinical implementation. We explored the feasibility of generating bivalent-Leuk-STs directed against Wilms tumour 1 (WT1) and preferentially expressed antigen in melanoma (PRAME) from umbilical cord blood units (UCBUs) disqualified for allogeneic haematopoietic stem cell transplantation. By repurposing non-transplantable UCBUs and optimising culture conditions, we consistently produced at clinical scale, both cluster of differentiation (CD)34+ cell-derived myeloid DCs and subsequently polyclonal bivalent-Leuk-STs. Those bivalent-Leuk-STs contained CD8+ and CD4+ T cell subsets predominantly of effector memory phenotype and presented high specificity and cytotoxicity against both WT1 and PRAME. In the present study, we provide a paradigm of circular economy by repurposing unusable UCBUs and a platform for future banking of Leuk-STs, as a 'third-party', 'off-the-shelf' T-cell product for the treatment of acute leukaemias.


Subject(s)
Antigens, Neoplasm/immunology , Dendritic Cells/immunology , Fetal Blood/cytology , Immunotherapy, Adoptive/methods , Leukemia/therapy , T-Cell Antigen Receptor Specificity , T-Lymphocyte Subsets/immunology , WT1 Proteins/immunology , Antigens, CD/analysis , Blood Banks/economics , Cell Differentiation , Cells, Cultured , Cord Blood Stem Cell Transplantation/standards , Cytotoxicity, Immunologic , Dendritic Cells/cytology , Dendritic Cells/transplantation , Humans , Immunomagnetic Separation , Immunophenotyping , Immunotherapy, Adoptive/economics , Leukemia/economics , Memory T Cells/immunology , Memory T Cells/transplantation , T-Lymphocyte Subsets/transplantation , T-Lymphocytes, Cytotoxic/immunology , T-Lymphocytes, Cytotoxic/transplantation
4.
Fish Shellfish Immunol ; 104: 337-346, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32540502

ABSTRACT

Listeria monocytogenes strains were isolated from Cornu aspersum maxima snails from farm units experiencing high mortalities and were characterized by phenotypic, molecular and biochemical criteria. A high heterogeneity was observed in the pulsed-field gel electrophoresis (PFGE) pulsotypes as well as in the virulence (13-100% mortality) among the fifteen L. monocytogenes strains. One strain was characterized as non-virulent while three strains exhibited hypervirulent phenotype. Hypervirulence activity was associated with cell surface properties such as hydrophobicity, autoaggregation and biofilm formation, with increased tolerance to snail's gut barriers such as pedal mucus, gastric mucus, gastric juices, and acidic pH as well as with increased capacity to resist the antibacterial activity of snail haemolymph and modulate immune cell populations and functions such as chemotaxis and phagocytoses. L. monocytogenes dysbiosis was characterized by a clinicopathological phenotype including immobilization of snails' headfoot outside the shell, increased mucus-secreting cells in the intestinal epithelium and feces, alteration of intestinal ridges morphology and excessive increase of haemolymph immune cells and cell death. Rebiosis in L. monocytogenes SN3 strain infected snails was achieved by dietary supplementation of the snail-gut commensal probiotic L. plantarum Sgs14 strain by exhibiting anti-Listeria activity, reducing mortality and clinicopathological manifestations as well as exhibiting immunomodulatory activity.


Subject(s)
Dysbiosis/therapy , Lactobacillus plantarum , Listeria monocytogenes , Listeriosis/microbiology , Probiotics/administration & dosage , Snails/microbiology , Animals , Dysbiosis/microbiology , Dysbiosis/veterinary , Gastrointestinal Microbiome , Hemolymph/cytology , Listeriosis/veterinary
5.
Fish Shellfish Immunol ; 92: 792-801, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31271839

ABSTRACT

The aim of this study was to determine the in vitro probiotic properties as well as the immunomodulatory activity of bacterial strains isolated from the gastrointestinal tract of the edible-farmed land snail Cornu aspersum maxima. Forty lactic acid bacterial strains (named Sgs1-40) were isolated from the intestinal tract and eight strains (named SgmA-H) from the oesophagus-crop of snails. Several criteria were used to examine whether they may be applied as snail-specific for the screening of the presumptive probiotic bacterial strains. Principal Component Analysis using criteria such as the tolerance of these strains to the pedal mucus, gastric mucus, gastric juices and low pH, as well as the expression of the cell surface traits of hydrophobicity, biofilm formation and autoaggregation capacity revealed discrimination of twelve strains exhibiting presumptive in vitro probiotic properties. Injection of eight of these strains, which were identified as Lactobacillus plantarum, in snail haemocoel increased the recruitment and phagocytic activity of amoebocytes in snail haemolymph. The Sgs14 and SgmB strains, exhibiting the highest immunostimulatory activity in haemolymph, were FITC-labelled and orally administrated to snails for ten days. The Sgs14 strain was able to adhere to intestinal mucosa of snails and stimulate the chemotactic and phagocytic activity of amoebocytes in haemolymph as well as the bactericidal activity of haemolymph serum. These responses are potentially mediated by the regulation of TLRs expression in the gut mucosa. These data indicate that the determination of properties such as snail mucus and gastric juice tolerance, cell surface traits for adhesion as well as increased chemotactic and phagocytic activity in snail haemolymph are eligible criteria to screen for snail-specific probiotics. To the best of our knowledge, this is the first work that investigates the probiotic properties of gastrointestinal microflora of the terrestrial farmed snail Cornu aspersum maxima.


Subject(s)
Gastrointestinal Microbiome , Immunologic Factors/pharmacology , Lactobacillus plantarum/chemistry , Probiotics/pharmacology , Snails/microbiology , Animals , Immunologic Factors/chemistry , Probiotics/chemistry
6.
Kidney Int ; 88(2): 276-85, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25807036

ABSTRACT

IgA1 complexes containing deglycosylated IgA1, IgG autoantibodies, and a soluble form of the IgA receptor (sCD89), are hallmarks of IgA nephropathy (IgAN). Food antigens, notably gluten, are associated with increased mucosal response and IgAN onset, but their implication in the pathology remains unknown. Here, an IgAN mouse model expressing human IgA1 and CD89 was used to examine the role of gluten in IgAN. Mice were given a gluten-free diet for three generations to produce gluten sensitivity, and then challenged for 30 days with a gluten diet. A gluten-free diet resulted in a decrease of mesangial IgA1 deposits, transferrin 1 receptor, and transglutaminase 2 expression, as well as hematuria. Mice on a gluten-free diet lacked IgA1-sCD89 complexes in serum and kidney eluates. Disease severity depended on gluten and CD89, as shown by reappearance of IgAN features in mice on a gluten diet and by direct binding of the gluten-subcomponent gliadin to sCD89. A gluten diet exacerbated intestinal IgA1 secretion, inflammation, and villous atrophy, and increased serum IgA1 anti-gliadin antibodies, which correlated with proteinuria in mice and patients. Moreover, early treatment of humanized mice with a gluten-free diet prevented mesangial IgA1 deposits and hematuria. Thus, gliadin-CD89 interaction may aggravate IgAN development through induction of IgA1-sCD89 complex formation and a mucosal immune response. Hence, early-stage treatment with a gluten-free diet could be beneficial to prevent disease.


Subject(s)
Antigens, CD/metabolism , Glomerulonephritis, IGA/immunology , Glomerulonephritis, IGA/metabolism , Glutens/toxicity , Immunoglobulin A/metabolism , Intestinal Mucosa/pathology , Receptors, Fc/metabolism , Animals , Antigens, CD/blood , Atrophy/etiology , Diet, Gluten-Free , Disease Models, Animal , Enteritis/etiology , GTP-Binding Proteins/metabolism , Gliadin/immunology , Gliadin/metabolism , Glomerulonephritis, IGA/diet therapy , Glutens/administration & dosage , Glutens/immunology , Hematuria/diet therapy , Hematuria/etiology , Immunoglobulin A/blood , Intestinal Mucosa/immunology , Intestinal Mucosa/metabolism , Male , Mice , Protein Glutamine gamma Glutamyltransferase 2 , Proteinuria/etiology , Receptors, Fc/blood , Receptors, Transferrin/metabolism , Transglutaminases/metabolism
7.
Blood Cells Mol Dis ; 53(3): 124-32, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24923531

ABSTRACT

Bone marrow (BM) could serve as a source of cells facilitating liver repopulation in case of hepatic damage. Currently available hematopoietic stem cell (HSC) mobilizing agents, were comparatively tested for healing potential in liver fibrosis. Carbon tetrachloride (CCl4)-injured mice previously reconstituted with Green Fluorescent Protein BM were mobilized with Granulocyte-Colony Stimulating Factor (G-CSF), Plerixafor or G-CSF+Plerixafor. Hepatic fibrosis, stellate cell activation and oval stem cell frequency were measured by Gomori and by immunohistochemistry for a-Smooth Muscle Actin and Cytokeratin-19, respectively. Angiogenesis was evaluated by ELISA and immunohistochemistry. Quantitative real-time PCR was used to determine the mRNA levels of liver Peroxisome Proliferator-Activated Receptor gamma (PPAR-γ), Interleukin-6 (IL-6) and Tumor Necrosis-alpha (TNFα). BM-derived cells were tracked by double immunofluorescence. The spontaneous migration of mobilized HSCs towards injured liver and its cytokine secretion profile was determined in transwell culture systems. Either single-agent mobilization or the combination of agents significantly ameliorated hepatic damage by decreasing fibrosis and restoring the abnormal vascular network in the liver of mobilized mice compared to CCl4-only mice. The degree of fibrosis reduction was similar among all mobilized mice despite that G-CSF+Plerixafor yielded significantly higher numbers of circulating HSCs over other agents. The liver homing potential of variously mobilized HSCs differed among the agents. An extended G-CSF treatment provided the highest anti-fibrotic effect over all tested modalities, induced by the proliferation of hepatic stem cells and decreased hepatic inflammation. Plerixafor-mobilized HSCs, despite their reduced liver homing potential, reversed fibrosis mainly by increasing hepatic PPAR-γ and VEGF expression. In all groups, BM-derived mature hepatocytes as well as liver-committed BM stem cells were detected only at low frequencies, further supporting the concept that alternative mechanisms rather than direct HSC effects regulate liver recovery. Overall, our data suggest that G-CSF, Plerixafor and G-CSF+Plerixafor act differentially during the wound healing process, ultimately providing a potent anti-fibrotic effect.


Subject(s)
Chemical and Drug Induced Liver Injury, Chronic/therapy , Hematopoietic Stem Cells/cytology , Liver Regeneration , Animals , Benzylamines , Biomarkers/metabolism , Carbon Tetrachloride/adverse effects , Chemical and Drug Induced Liver Injury, Chronic/diagnosis , Chemical and Drug Induced Liver Injury, Chronic/metabolism , Chemical and Drug Induced Liver Injury, Chronic/mortality , Cyclams , Fibrosis , Granulocyte Colony-Stimulating Factor/administration & dosage , Hematopoietic Stem Cell Mobilization , Hematopoietic Stem Cells/drug effects , Heterocyclic Compounds/administration & dosage , Immunohistochemistry , Liver/drug effects , Liver/metabolism , Liver/pathology , Mice , Time Factors
8.
Sci Total Environ ; 941: 173554, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-38823724

ABSTRACT

In the current study, the genotypic characteristics such as antimicrobial resistance and virulence genes, and plasmid replicons and phenotypic characteristics such as biofilm formation and antimicrobial resistance of 87 extended-spectrum beta-lactamase (ESBL)-producing E. coli (ESBL-Ec) isolated from 7 water bodies in northern Greece were investigated. Our data show a high prevalence (60.0 %) of ESBL-Ec in surface waters that exhibit high genetic diversity, suggesting multiple sources of their transmission into the aquatic environment. When evaluating the antimicrobial resistance of isolates, wide variation in their resistance profiles has been detected, with all isolates being multi-drug resistant (MDR). Regarding biofilm formation capacity and phylogenetic groups, the majority (54.0 %, 47/87) of ESBL-Ec were classified as no biofilm producers mainly assigned to phylogroup A (35.6 %; 31/87), followed by B2 (26.5 %; 23/87). PCR screening showed that a high proportion of the isolates tested positive for the blaCTX-M-1 group genes (69 %, 60/87), followed by blaTEM (55.2 %, 48/87), blaOXA (25.3 %, 22/87) and blaCTX-M-9 (17.2 %, 15/87). A subset of 28 ESBL-Ec strains was further investigated by applying whole genome sequencing (WGS), and among them, certain clinically significant sequence types were identified, such as ST131 and ST10. The corresponding in silico analysis predicted all these isolates as human pathogens, while a significant proportion of WGS-ESBL-Ec were assigned to extraintestinal pathogenic E. coli (ExPEC; 32.1 %), and urinary pathogenic E. coli (UPEC; 28.6 %) pathotypes. Comparative phylogenetic analysis, showed that the genomes of the ST131-O25:H4-H30 isolates are genetically linked to the human clinical strains. Here, we report for the first time the detection of a plasmid-mediated mobile colistin resistance gene in ESBL-Ec in Greece isolated from an environmental source. Overall, this study underlines the role of surface waters as a reservoir for antibiotic resistance genes and for presumptive pathogenic ESBL-Ec.


Subject(s)
Escherichia coli , Rivers , beta-Lactamases , Escherichia coli/genetics , Greece , beta-Lactamases/genetics , Rivers/microbiology , Phylogeny
9.
Lab Invest ; 92(4): 625-35, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22330344

ABSTRACT

Coeliac disease (CD) is a malabsorptive enteropathy resulting from intolerance to gluten. Environmental factors and the microbiota are suggested to have critical roles in the onset of CD. The CD71 IgA receptor on epithelial cells is responsible for abnormal retrotranscytosis of IgA-gluten peptide complexes from the intestinal lumen into the lamina propria, inducing intestinal inflammation. However, understanding the role of gluten in the CD physiopathology has been hindered by the absence of relevant animal models. Here, we generated a mouse model for CD to study the factors controlling its pathogenesis as well as to investigate the influence of oral delivery of probiotics on disease development. Gluten sensitivity was established by feeding three generations of BALB/c mice a gluten-free diet (G-) followed by gluten challenge (G+) for 30 days. The G+ mice developed villous atrophy, crypt hyperplasia and infiltration of T cells and macrophages in the small intestine. Inflammation was associated with an overexpression of CD71 on the apical side of enterocytes and an increase of plasma cells producing IgA, which colocalised with the CD71. Moreover, IgA colocalised with the transglutaminase 2 (TG2), the production of which was increased in the lamina propria of G+ mice. These mice displayed increased production of cyclooxygenase-2 (COX-2), pro-inflammatory cytokines and IL-15, as well as anti-gliadin and anti-TG2 autoantibodies. The commensal flora-isolated presumptive probiotic Saccharomyces boulardii KK1 strain hydrolysed the 28-kDa α-gliadin fraction, and its oral delivery in G+ mice improved enteropathy development in association with decrease of epithelial cell CD71 expression and local cytokine production. In conclusion, the G+ BALB/c mouse represents a new mouse model for human CD based on histopathological features and expression of common biomarkers. The selected probiotic treatment reversing disease development will allow the study of the role of probiotics as a new therapeutic approach of CD.


Subject(s)
Antigens, CD/metabolism , Celiac Disease/etiology , Disease Models, Animal , GTP-Binding Proteins/metabolism , Glutens/adverse effects , Immunoglobulin A/metabolism , Receptors, Transferrin/metabolism , Transglutaminases/metabolism , Adaptive Immunity , Animals , Celiac Disease/metabolism , Celiac Disease/prevention & control , Enterocytes/metabolism , Female , Glutens/immunology , Immunity, Innate , Intestinal Mucosa/immunology , Intestine, Small/immunology , Male , Mice , Mice, Inbred BALB C , Probiotics/therapeutic use , Protein Glutamine gamma Glutamyltransferase 2 , Saccharomyces
10.
Ann Rheum Dis ; 71(10): 1733-40, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22586171

ABSTRACT

OBJECTIVE: The role of mesenchymal stem cells (MSC) in experimental arthritis is undoubtedly conflicting. This study explored the effect of bone marrow-derived MSC in previously untested and pathogenetically different models of rheumatoid arthritis (RA). METHODS: MSC were tested both in an induced (adjuvant-induced) and a spontaneous (K/BxN) arthritis model. Arthritis was assessed clinically and histologically. The proliferation of splenocytes and fibroblast-like synoviocytes (FLS) in the presence of MSC was measured by radioactivity incorporation. Toll-like receptor (TLR) expression was measured by real-time PCR. T-regulatory cell (Treg) frequency, T-cell apoptosis and cytokine secretion were monitored by flow cytometry. RESULTS: MSC, in vitro, strongly inhibited critical cell populations; splenocytes and FLS. In contrast, MSC proved ineffective in vivo, unless they were administered before disease onset, an effect implying that the inflammatory arthritic milieu potentially abrogates MSC immunomodulatory properties. In order to alleviate inflammation before MSC infusion, the authors administered, at arthritis onset, a short course with a proteasome inhibitor, bortezomib, whereas MSC were infused when established disease was expected. The bortezomib plus MSC group demonstrated a significantly decreased arthritis score over arthritic, MSC-only, bortezomib-only groups, also confirmed by histology and immunohistochemistry. The bortezomib plus MSC combination restored TLR expression and Treg frequency in blood and normalised FLS and splenocyte proliferation, apoptosis and cytokine secretion. CONCLUSION: MSC lose their immunomodulatory properties when infused in the inflammatory micromilieu of autoimmune arthritis. Conditioning of the recipient with bortezomib alters the disease microenvironment enabling MSC to modulate arthritis. Should milieu limitations also operate in human disease, this approach could serve as a strategy to treat RA by MSC.


Subject(s)
Antirheumatic Agents/administration & dosage , Arthritis, Experimental/therapy , Arthritis, Rheumatoid/therapy , Boronic Acids/administration & dosage , Mesenchymal Stem Cell Transplantation/methods , Pyrazines/administration & dosage , T-Lymphocytes/immunology , Animals , Arthritis, Experimental/immunology , Arthritis, Rheumatoid/immunology , Bortezomib , Disease Models, Animal , Flow Cytometry , Mice , Mice, Inbred C57BL , Mice, Transgenic , Rats , Rats, Inbred F344 , Rats, Inbred Lew , Real-Time Polymerase Chain Reaction
11.
PLoS Comput Biol ; 6(7): e1000847, 2010 Jul 08.
Article in English | MEDLINE | ID: mdl-20628614

ABSTRACT

The mechanisms of stress tolerance in sessile animals, such as molluscs, can offer fundamental insights into the adaptation of organisms for a wide range of environmental challenges. One of the best studied processes at the molecular level relevant to stress tolerance is the heat shock response in the genus Mytilus. We focus on the upstream region of Mytilus galloprovincialis Hsp90 genes and their structural and functional associations, using comparative genomics and network inference. Sequence comparison of this region provides novel evidence that the transcription of Hsp90 is regulated via a dense region of transcription factor binding sites, also containing a region with similarity to the Gamera family of LINE-like repetitive sequences and a genus-specific element of unknown function. Furthermore, we infer a set of gene networks from tissue-specific expression data, and specifically extract an Hsp class-associated network, with 174 genes and 2,226 associations, exhibiting a complex pattern of expression across multiple tissue types. Our results (i) suggest that the heat shock response in the genus Mytilus is regulated by an unexpectedly complex upstream region, and (ii) provide new directions for the use of the heat shock process as a biosensor system for environmental monitoring.


Subject(s)
Models, Genetic , Mytilus/genetics , Stress, Physiological/genetics , Analysis of Variance , Animals , Base Sequence , Cluster Analysis , Conserved Sequence , Gene Expression Profiling , HSP90 Heat-Shock Proteins/genetics , HSP90 Heat-Shock Proteins/metabolism , Long Interspersed Nucleotide Elements/genetics , Models, Statistical , Molecular Sequence Data , Neoplasms/genetics , Organ Specificity , Principal Component Analysis , Promoter Regions, Genetic , Sequence Alignment , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism
12.
Arthritis Rheum ; 62(11): 3277-88, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20722034

ABSTRACT

OBJECTIVE: To explore the effect of bortezomib in splenocytes and fibroblast-like synoviocytes (FLS) and its in vivo potency in a rat model of adjuvant-induced arthritis (AIA), which resembles human rheumatoid arthritis (RA). METHODS: AIA was induced with Freund's complete adjuvant. Splenocyte and FLS proliferation and apoptosis were measured by radioactivity incorporation and flow cytometry, respectively. The invasiveness of FLS from rats with AIA was tested in a Transwell system. The pattern of cytokine secretion was evaluated by cytometric bead array in splenocyte supernatants. Bortezomib was administered prophylactically or therapeutically, and arthritis was assessed clinically and histologically. Immunohistochemistry was performed for markers of inflammation and angiogenesis in joints. Hematologic and biochemical parameters were tested in peripheral blood (PB). Representative animals were examined by computed tomography (CT) scanning before and after bortezomib administration. The expression of Toll-like receptor 2 (TLR-2), TLR-3, and TLR-4 in PB and FLS was measured by real-time polymerase chain reaction, and alterations in specific cell populations in PB and spleen were determined by flow cytometry. RESULTS: In vitro, bortezomib exhibited significant inhibitory and proapoptotic activity in splenocytes and FLS from rats with AIA, altered the inflammatory cytokine pattern, and reduced the invasiveness of FLS from rats with AIA. In vivo, bortezomib significantly ameliorated disease severity. Remission was associated with improved histology and decreased expression of CD3, CD79a, CD11b, cyclooxygenase 1, and factor VIII in target tissues as well as down-regulation of TLR expression in PB and cultured FLS. CT scanning demonstrated a bone healing effect after treatment. CONCLUSION: Our findings suggest that bortezomib affects AIA in a pleiotropic manner and that this drug may be effective in RA.


Subject(s)
Arthritis, Experimental/drug therapy , Arthritis, Rheumatoid/drug therapy , Bone Diseases/drug therapy , Boronic Acids/therapeutic use , Inflammation/drug therapy , Joints/drug effects , Pyrazines/therapeutic use , Analysis of Variance , Animals , Arthritis, Experimental/metabolism , Arthritis, Experimental/pathology , Arthritis, Rheumatoid/metabolism , Arthritis, Rheumatoid/pathology , Bone Diseases/metabolism , Bone Diseases/pathology , Bortezomib , Cell Proliferation , Cytokines/metabolism , Flow Cytometry , Immunohistochemistry , Inflammation/metabolism , Inflammation/pathology , Joints/metabolism , Joints/pathology , Rats , Rats, Inbred Lew , Reverse Transcriptase Polymerase Chain Reaction , Spleen/drug effects , Spleen/metabolism , Spleen/pathology , Synovial Membrane/drug effects , Synovial Membrane/metabolism , Synovial Membrane/pathology , Toll-Like Receptors/metabolism , Treatment Outcome
13.
Nat Commun ; 12(1): 6790, 2021 11 23.
Article in English | MEDLINE | ID: mdl-34815405

ABSTRACT

Lineage commitment and differentiation is driven by the concerted action of master transcriptional regulators at their target chromatin sites. Multiple efforts have characterized the key transcription factors (TFs) that determine the various hematopoietic lineages. However, the temporal interactions between individual TFs and their chromatin targets during differentiation and how these interactions dictate lineage commitment remains poorly understood. Here we perform dense, daily, temporal profiling of chromatin accessibility (DNase I-seq) and gene expression changes (total RNA-seq) along ex vivo human erythropoiesis to comprehensively define developmentally regulated DNase I hypersensitive sites (DHSs) and transcripts. We link both distal DHSs to their target gene promoters and individual TFs to their target DHSs, revealing that the regulatory landscape is organized in distinct sequential regulatory modules that regulate lineage restriction and maturation. Finally, direct comparison of transcriptional dynamics (bulk and single-cell) and lineage potential between erythropoiesis and megakaryopoiesis uncovers differential fate commitment dynamics between the two lineages as they exit the stem and progenitor stage. Collectively, these data provide insights into the temporally regulated synergy of the cis- and the trans-regulatory components underlying hematopoietic lineage commitment and differentiation.


Subject(s)
Cell Lineage/genetics , Chromatin/genetics , Gene Expression Regulation, Developmental , Hematopoiesis/genetics , Hematopoietic Stem Cells/physiology , Cell Line , Chromatin/metabolism , Colony-Forming Units Assay , Deoxyribonuclease I/metabolism , Humans , Leukocytes, Mononuclear , Primary Cell Culture , Promoter Regions, Genetic , RNA-Seq , Single-Cell Analysis , Transcription Factors/metabolism
14.
Hum Gene Ther ; 32(19-20): 1186-1199, 2021 10.
Article in English | MEDLINE | ID: mdl-34477013

ABSTRACT

Despite the unequivocal success of hematopoietic stem and progenitor cell gene therapy, limitations still exist including genotoxicity and variegation/silencing of transgene expression. A class of DNA regulatory elements known as chromatin insulators (CIs) can mitigate both vector transcriptional silencing (barrier CIs) and vector-induced genotoxicity (enhancer-blocking CIs) and have been proposed as genetic modulators to minimize unwanted vector/genome interactions. Recently, a number of human, small-sized, and compact CIs bearing strong enhancer-blocking activity were identified. To ultimately uncover an ideal CI with a dual, enhancer-blocking and barrier activity, we interrogated these elements in vitro and in vivo. After initial screening of a series of these enhancer-blocking insulators for potential barrier activity, we identified three distinct categories with no, partial, or full protection against transgene silencing. Subsequently, the two CIs with full barrier activity (B4 and C1) were tested for their ability to protect against position effects in primary cells, after incorporation into lentiviral vectors (LVs) and transduction of human CD34+ cells. B4 and C1 did not adversely affect vector titers due to their small size, while they performed as strong barrier insulators in CD34+ cells, both in vitro and in vivo, shielding transgene's long-term expression, more robustly when placed in the forward orientation. Overall, the incorporation of these dual-functioning elements into therapeutic viral vectors will potentially provide a new generation of safer and more efficient LVs for all hematopoietic stem cell gene therapy applications.


Subject(s)
Chromatin , Insulator Elements , Chromatin/genetics , Enhancer Elements, Genetic , Genetic Therapy , Genetic Vectors/genetics , Hematopoietic Stem Cells , Humans , Insulator Elements/genetics
15.
J Biol Res (Thessalon) ; 26: 4, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31360678

ABSTRACT

BACKGROUND: Hematopoiesis is a model-system for studying cellular development and differentiation. Phenotypic and functional characterization of hematopoietic progenitors has significantly aided our understanding of the mechanisms that govern fate choice, lineage specification and maturity. Methods for progenitor isolation have historically relied on complex flow-cytometric strategies based on nested, arbitrary gates within defined panels of immunophenotypic markers. The resulted populations are then functionally assessed, although functional homogeneity or absolute linkage between function and phenotype is not always achieved, thus distorting our view on progenitor biology. METHOD: In this study, we present a protocol for unbiased phenotypic identification and functional characterization which combines index sorting and clonogenic assessment of individual progenitor cells. Single-cells are plated into custom media allowing multiple hematopoietic fates to emerge and are allowed to give rise to unilineage colonies or mixed. After colony identification, lineage potential is assigned to each progenitor and finally the indexed phenotype of the initial cell is recalled and a phenotype is assigned to each functional output. CONCLUSIONS: Our approach overcomes the limitations of the current protocols expanding beyond the established cell-surface marker panels and abolishing the need for nested gating. Using this method we were able to resolve the relationships of myeloid progenitors according to the revised model of hematopoiesis, as well as identify a novel marker for erythroid progenitors. Finally, this protocol can be applied to the characterization of any progenitor cell with measurable function.

16.
Bone Marrow Transplant ; 54(12): 1963-1972, 2019 12.
Article in English | MEDLINE | ID: mdl-30867554

ABSTRACT

Invasive aspergillosis (IA) represents a leading cause of mortality in immunocompromised patients. Although adoptive immunotherapy with Aspergillus-specific T cells (Asp-STs) represents a promising therapeutic approach against IA, the complex and costly production limits its broader application. We generated Asp-STs from a single blood draw of healthy individuals or IA patients in only 10 days, by either Aspergillus fumigatus (AF) lysate or peptide stimulation of mononuclear cells. The cells were phenotypically and functionally characterized, and safety was assessed in xenografts. Healthy donor-derived and lysate- or peptide-pulsed Asp-STs presented comparable fold expansion, immunophenotype, and Th1 responses. Upon cross-stimulation, only the lysate-pulsed Asp-STs were empowered to respond to peptide stimulation, although both cell products induced hyphal damage. Importantly, Asp-STs cross-reacted with other fungal species and did not induce alloreactivity in vivo. IA patient-derived T cells displayed an anergic phenotype that prohibited sufficient expansion and yield of meaningful doses of Asp-STs for autologous immunotherapy. Using a rapid and simple process, we generated, from healthy donors but not IA patients, functionally active Asp-STs of broad specificity and at clinically relevant numbers. Such an approach may form the basis for the effective management of IA in the context of allogeneic hematopoietic cell transplantation.

18.
Water Res ; 42(4-5): 1274-80, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18001812

ABSTRACT

Enterococcus includes species that may pose emerging health risks and has been used as biomarkers for environmental contamination while little is known concerning their occurrence in marine water. Classification of enterococci in environmental samples can be problematic and requires polyphasic taxonomy. In this study, we investigated the presence of vancomycin-resistant enterococci (VRE) in the inner bay of Thermaikos Gulf in Northern Greece. Based on physiological and biochemical criteria, 121 presumptive enterococcal strains were identified. High-level VRE were undetectable in seawater and only 35 vancomycin gene-negative strains possessed low-level vancomycin resistance. Genotyping by pulsed field gel electrophoresis (PFGE) proved to be more reliable for marine enterococcal discrimination and revealed distinguished characteristics of the seawater enterococci, indicating high genetic diversity. Random amplified polymorphic DNA-PCR (RAPD-PCR) was unable to separate distinct species analyzed in this study. This study indicates the need of polyphasic taxonomy for seawater enterococcal species' identification and provides information for future biomonitoring programs of Thermaikos Gulf.


Subject(s)
Enterococcus/isolation & purification , Seawater/microbiology , Vancomycin Resistance , Water Pollutants/isolation & purification , Anti-Bacterial Agents/pharmacology , DNA, Bacterial/genetics , Enterococcus/drug effects , Enterococcus/genetics , Environmental Monitoring , Genes, Bacterial/genetics , Genotype , Greece , Microbial Sensitivity Tests , Phenotype , Polymerase Chain Reaction , Vancomycin/pharmacology
19.
Water Res ; 143: 56-65, 2018 10 15.
Article in English | MEDLINE | ID: mdl-29940362

ABSTRACT

Membrane biofouling, due to Soluble Microbial Products (SMP) and Extracellular Polymeric Substances (EPS) deposition, results in reduction of the performance of Membrane Bioreactors (MBRs). However, recently, a new method of biofouling control has been developed, utilizing the interference of the bacterial inter- and intra-species' communication. Bacteria use Quorum Sensing (QS) to regulate the production of SMP and EPS. Therefore, disruption of Quorum Sensing (Quorum Quenching: QQ), by enzymes or microorganisms, may be a simple mean to control membrane biofouling. In the present study, a novel QQ-bacterium, namely Lactobacillus sp. SBR04MA, was isolated from municipal wastewater sludge and its ability to mitigate biofouling was evaluated by monitoring the changes in critical flux and transmembrane pressure, along with the production of EPS and SMP, in a lab-scale MBR system treating synthetic wastewater. Lactobacillus sp. SBR04MA showed great potential for biofouling control, which was evidenced by the ∼3-fold increase in critical flux (8.3 → 24.25 L/m2/h), as well as by reduction of the SMP and EPS production, which was lower during the QQ-period when compared against the control period. Furthermore, the addition of the QQ-strain did not affect the COD removal rate. Results suggested that Lactobacillus sp. SBR04MA represents a novel and promising strain for biofouling mitigation and enhancement of MBRs performance.


Subject(s)
Biofouling/prevention & control , Bioreactors/microbiology , Lactobacillus/physiology , Quorum Sensing/physiology , Waste Disposal, Fluid/methods , Bacteria , Membranes, Artificial , Pressure , Sewage/microbiology , Waste Disposal, Fluid/instrumentation , Wastewater
20.
Vet Microbiol ; 88(4): 325-38, 2002 Sep 24.
Article in English | MEDLINE | ID: mdl-12220808

ABSTRACT

Traditionally, adjuvants have been administered with antigens to enhance immunity. We studied the effect of several adjuvants such as Freund's complete adjuvant (FCA), Freund's incomplete adjuvant (FIA), lipopolysaccharide (LPS), homopolymers of polyinosinic-polycytidylic acid (poly I:C) and polyadenylic-polyuridylic acid (poly A:U), lithium chloride (LiCl), saponin Quil A and calcium phosphate gel (CaHPO(4)) on the immune response of mice to formalin-inactivated Mycoplasma agalactiae. The specific antibody or cytokine producing splenocytes were detected by ELISAspot and immunocytochemistry, respectively. Depending on the adjuvant given, the number of M. agalactiae-specific antibody producing cells was increased 2.5-6-fold. IgG was the major class of M. agalactiae-specific antibodies followed by IgM, IgA and IgE. Among IgG isotypes, FCA, FIA, Quil A and CaHPO(4) induced an IgG1 response with substantial increase of the IgG2a, IgG2b and IgG3 isotypes while poly I:C shifted the response toward an IgG2a/IgG3 production. Finally, poly A:U induced an IgG2b response while LPS and LiCl augmented the IgG3/IgG1/IgG2a secretion. FCA augmented IL-4, IL-5 and IL-10 production suggesting a strong Th2 response, while IFN-gamma and IL-12 remained low; poly I:C enhanced IFN-gamma, IL-12 and TNF-alpha eliciting a Th1 response; poly A:U resulted in a IL-10, IL-5, IL-6 and IL-12 secretion; and LPS enhanced the IL-10, IL-6 and TNF-alpha production. Our data show that adjuvants augment M. agalactiae-specific antibody production and lead to B cell isotype-switching via the appropriate cytokine milieu. Certain adjuvants, such as poly I:C, therefore, appear as promising immune enhancers for vaccination against M. agalactiae infections.


Subject(s)
Adjuvants, Immunologic/pharmacology , Cytokines/biosynthesis , Immunoglobulin Isotypes/immunology , Mycoplasma Infections/immunology , Mycoplasma/immunology , Animals , Antigens, Bacterial/biosynthesis , Antigens, Bacterial/immunology , Bacterial Vaccines/immunology , Bacterial Vaccines/pharmacology , Cytokines/metabolism , Enzyme-Linked Immunosorbent Assay , Immunization/methods , Immunoglobulin Class Switching/immunology , Immunoglobulin Isotypes/biosynthesis , Immunohistochemistry , Mice , Mice, Inbred BALB C , Mycoplasma Infections/metabolism , Vaccines, Inactivated/immunology , Vaccines, Inactivated/pharmacology
SELECTION OF CITATIONS
SEARCH DETAIL