RESUMO
Globally, mental disorders account for almost 20% of disease burden and there is growing evidence that mental disorders are socially determined. Tackling the United Nations Sustainable Development Goals (UN SDGs), which address social determinants of mental disorders, may be an effective way to reduce the global burden of mental disorders. We conducted a systematic review of reviews to examine the evidence base for interventions that map onto the UN SDGs and seek to improve mental health through targeting known social determinants of mental disorders. We included 101 reviews in the final review, covering demographic, economic, environmental events, neighborhood, and sociocultural domains. This review presents interventions with the strongest evidence base for the prevention of mental disorders and highlights synergies where addressing the UN SDGs can be beneficial for mental health.
Assuntos
Transtornos Mentais , Determinantes Sociais da Saúde , Desenvolvimento Sustentável , Humanos , Transtornos Mentais/terapia , Nações Unidas , Saúde GlobalRESUMO
Rapid bone destruction often leads to permanent joint dysfunction in patients with septic arthritis, which is mainly caused by Staphylococcus aureus (S. aureus). Staphylococcal cell wall components are known to induce joint inflammation and bone destruction. Here, we show that a single intra-articular injection of S. aureus lipoproteins (Lpps) into mouse knee joints induced chronic destructive macroscopic arthritis through TLR2. Arthritis was characterized by rapid infiltration of neutrophils and monocytes. The arthritogenic effect was mediated mainly by macrophages/monocytes and partially via TNF-α but not by neutrophils. Surprisingly, a S. aureus mutant lacking Lpp diacylglyceryl transferase (lgt) caused more severe joint inflammation, which coincided with higher bacterial loads of the lgt mutant in local joints than those of its parental strain. Coinjection of pathogenic S. aureus LS-1 with staphylococcal Lpps into mouse knee joints caused improved bacterial elimination and diminished bone erosion. The protective effect of the Lpps was mediated by their lipid moiety and was fully dependent on TLR2 and neutrophils. The blocking of CXCR2 on neutrophils resulted in total abrogation of the protective effect of the Lpps. Our data demonstrate that S. aureus Lpps elicit innate immune responses, resulting in a double-edged effect. On the one hand, staphylococcal Lpps boost septic arthritis. On the other hand, Lpps act as adjuvants and activate innate immunity, which could be useful for combating infections with multiple drug-resistant strains.
Assuntos
Artrite/imunologia , Proteínas de Bactérias/imunologia , Lipoproteínas/imunologia , Neutrófilos/imunologia , Staphylococcus aureus/imunologia , Animais , Artrite/genética , Artrite/microbiologia , Artrite/patologia , Proteínas de Bactérias/genética , Feminino , Lipoproteínas/genética , Camundongos , Neutrófilos/patologia , Receptores de Interleucina-8B/genética , Receptores de Interleucina-8B/imunologia , Infecções Estafilocócicas/genética , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/patologia , Staphylococcus aureus/genética , Staphylococcus aureus/patogenicidade , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/imunologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologiaRESUMO
Staphylococcus aureus, a versatile Gram-positive bacterium, is the main cause of bone and joint infections (BJI), which are prone to recurrence. The inflammasome is an immune signaling platform that assembles after pathogen recognition. It activates proteases, most notably caspase-1 that proteolytically matures and promotes the secretion of mature IL-1ß and IL-18. The role of inflammasomes and caspase-1 in the secretion of mature IL-1ß and in the defence of S. aureus-infected osteoblasts has not yet been fully investigated. We show here that S. aureus-infected osteoblast-like MG-63 but not caspase-1 knock-out CASP1 -/- MG-63 cells, which were generated using CRISPR-Cas9 technology, activate the inflammasome as monitored by the release of mature IL-1ß. The effect was strain-dependent. The use of S. aureus deletion and complemented phenole soluble modulins (PSMs) mutants demonstrated a key role of PSMs in inflammasomes-related IL-1ß production. Furthermore, we found that the lack of caspase-1 in CASP1 -/- MG-63 cells impairs their defense functions, as bacterial clearance was drastically decreased in CASP1 -/- MG-63 compared to wild-type cells. Our results demonstrate that osteoblast-like MG-63 cells play an important role in the immune response against S. aureus infection through inflammasomes activation and establish a crucial role of caspase-1 in bacterial clearance.
Assuntos
Caspase 1/genética , Caspase 1/imunologia , Inflamassomos/imunologia , Osteoblastos/microbiologia , Staphylococcus aureus/patogenicidade , Sistemas CRISPR-Cas , Linhagem Celular , Deleção de Genes , Humanos , Inflamassomos/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Células THP-1RESUMO
Staphylococcus aureus is a facultative intracellular pathogen. Recently, it has been shown that the protein part of the lipoprotein-like lipoproteins (Lpls), encoded by the lpl cluster comprising of 10 lpls paralogue genes, increases pathogenicity, delays the G2/M phase transition, and also triggers host cell invasion. Here, we show that a recombinant Lpl1 protein without the lipid moiety binds directly to the isoforms of the human heat shock proteins Hsp90α and Hsp90ß. Synthetic peptides covering the Lpl1 sequence caused a twofold to fivefold increase of S. aureus invasion in HaCaT cells. Antibodies against Hsp90 decrease S. aureus invasion in HaCaT cells and in primary human keratinocytes. Additionally, inhibition of ATPase function of Hsp90 or silencing Hsp90α expression by siRNA also decreased the S. aureus invasion in HaCaT cells. Although the Hsp90ß is constitutively expressed, the Hsp90α isoform is heat-inducible and appears to play a major role in Lpl1 interaction. Pre-incubation of HaCaT cells at 39°C increased both the Hsp90α expression and S. aureus invasion. Lpl1-Hsp90 interaction induces F-actin formation, thus, triggering an endocytosis-like internalisation. Here, we uncovered a new host cell invasion principle on the basis of Lpl-Hsp90 interaction.
Assuntos
Proteínas de Bactérias/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Lipoproteínas/metabolismo , Staphylococcus aureus/genética , Staphylococcus aureus/patogenicidade , Actinas/metabolismo , Proteínas de Bactérias/genética , Células Cultivadas , Endocitose , Prepúcio do Pênis/citologia , Proteínas de Choque Térmico HSP90/genética , Células HaCaT , Interações Hospedeiro-Patógeno , Humanos , Queratinócitos/microbiologia , Lipoproteínas/genética , Masculino , Proteínas RecombinantesRESUMO
Intracellular persistence of Staphylococcus aureus favors bacterial spread and chronic infections. Here, we provide evidence for the existence of human CD4+ and CD8+ T cell memory against staphylococcal antigens. Notably, the latter could provide a missing link in our understanding of immune control of intracellular S. aureus. The analyses showed that pulsing of monocyte-derived dendritic cells (MoDC) with native staphylococcal protein antigens induced release of Th2-associated cytokines and mediators linked to T regulatory cell development (G-CSF, IL-2 and IL-10) from both CD4+ and CD8+ T cells, thus revealing a state of tolerance predominantly arising from preformed memory T cells. Furthermore, G-CSF was identified as a suppressor of CD8+ T cell-derived IFNγ secretion, thus confirming a tolerogenic role of this cytokine in the regulation of T cell responses to S. aureus. Nevertheless, delivery of in vitro transcribed mRNA-encoded staphylococcal antigens triggered Th1-biased responses, e.g. IFNγ and TNF release from both naïve and memory T cells. Collectively, our data highlight the potential of mRNA-adjuvanted antigen presentation to enable inflammatory responses, thus overriding the existing Th2/Treg-biased memory T cell response to native S. aureus antigens.
Assuntos
Antígenos de Bactérias/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Infecções Estafilocócicas/imunologia , Staphylococcus aureus/imunologia , Apresentação de Antígeno , Citocinas/imunologia , Fator Estimulador de Colônias de Granulócitos/imunologia , Humanos , Tolerância Imunológica , Interleucina-10/imunologia , Interleucina-2/imunologia , Infecções Estafilocócicas/microbiologia , Linfócitos T Reguladores/imunologia , Células Th2/imunologiaRESUMO
The use of pre-implantation genetic diagnosis (PGD) is increasing as the list of indications it can test for constantly expands. This raises new challenges for clinicians and prospective parents regarding possible uses and calls for guidance. Policy approaches towards PGD vary greatly worldwide. The 2004 Canadian Assisted Human Reproduction Act does not provide guidance, except for prohibiting non-medical sex selection. Criminal legislation is an unsuitable policy instrument to regulate human genetics and reproductive medicine. We call for professional societies to issue guidelines regarding the uses of PGD that would establish the standard of care and legal norms. Such guidelines should be based on a patient-centered approach and respect individual autonomy in reproductive decision-making. Canadian approaches to PGD should also consider issues related to equity of access. Moreover, since PGD often raises concerns about eugenic uses, guidelines should also consider its societal impact and its implementation should be accompanied by policies that maintain or increase social support for people with disabilities. Finally, public engagement could provide an evidence-base regarding Canadian societal values and concerns that should guide regulatory reform, for example, the regulation of non-medical sex selection through PGD.
Assuntos
Política de Saúde , Guias de Prática Clínica como Assunto , Diagnóstico Pré-Implantação , Canadá , Participação da Comunidade , Feminino , Equidade em Saúde , Acessibilidade aos Serviços de Saúde , Humanos , Assistência Centrada no Paciente , Autonomia Pessoal , Gravidez , Valores SociaisRESUMO
BACKGROUND: Rare Disease research has seen tremendous advancements over the last decades, with the development of new technologies, various global collaborative efforts and improved data sharing. To maximize the impact of and to further build on these developments, there is a need for model consent clauses for rare diseases research, in order to improve data interoperability, to meet the informational needs of participants, and to ensure proper ethical and legal use of data sources and participants' overall protection. METHODS: A global Task Force was set up to develop model consent clauses specific to rare diseases research, that are comprehensive, harmonized, readily accessible, and internationally applicable, facilitating the recruitment and consent of rare disease research participants around the world. Existing consent forms and notices of consent were analyzed and classified under different consent themes, which were used as background to develop the model consent clauses. RESULTS: The IRDiRC-GA4GH MCC Task Force met in September 2018, to discuss and design model consent clauses. Based on analyzed consent forms, they listed generic core elements and designed the following rare disease research specific core elements; Rare Disease Research Introductory Clause, Familial Participation, Audio/Visual Imaging, Collecting, storing, sharing of rare disease data, Recontact for matching, Data Linkage, Return of Results to Family Members, Incapacity/Death, and Benefits. CONCLUSION: The model consent clauses presented in this article have been drafted to highlight consent elements that bear in mind the trends in rare disease research, while providing a tool to help foster harmonization and collaborative efforts.
Assuntos
Pesquisa Biomédica/ética , Termos de Consentimento/normas , Consentimento Livre e Esclarecido/normas , Doenças Raras/terapia , Pesquisa Biomédica/métodos , Pesquisa Biomédica/normas , Termos de Consentimento/ética , Humanos , Consentimento Livre e Esclarecido/éticaRESUMO
Staphylococcus aureus contains a certain subclass of lipoproteins, the so-called lipoprotein-like lipoproteins (Lpl's), that not only represent Toll-like receptor 2 (TLR2) ligands but are also involved in host cell invasion. Here we addressed the question of which factors contribute to Lpl-mediated invasion of epithelial cells and keratinocytes. For this purpose, we compared the invasiveness of USA300 and its Δlpl mutant under different conditions. In the presence of the matrix proteins IgG, fibrinogen (Fg), and fibronectin (Fn), and of fetal bovine serum (FBS), the invasion ratio was increased in both strains, and always more in USA300 than in its Δlpl mutant. Interestingly, when we compared the invasion of HEK-0 and HEK-TLR2 cells, the cells expressing TLR2 showed a 9-times-higher invasion frequency. When HEK-TLR2 cells were additionally stimulated with a synthetic lipopeptide, Pam3CSK4 (P3C), the invasion frequency was further increased. A potential reason for the positive effect of TLR2 on invasion could be that TLR2 activation by P3C also activates F-actin formation. Here we show that S. aureus invasion depends on a number of factors, on the host side as well as on the bacterial side.
Assuntos
Proteínas de Bactérias/metabolismo , Endocitose , Células Epiteliais/microbiologia , Interações Hospedeiro-Patógeno , Lipoproteínas/metabolismo , Staphylococcus aureus/patogenicidade , Receptor 2 Toll-Like/metabolismo , Actinas/metabolismo , Linhagem Celular , Deleção de Genes , Humanos , Queratinócitos/microbiologia , Lipoproteínas/genéticaRESUMO
Particularly in Asia medicinal plants with antimicrobial activity are used for therapeutic purpose. One such plant-derived antibiotic is rhodomyrtone (Rom) isolated from Rhodomyrtus tomentosa leaves. Rom shows high antibacterial activity against a wide range of Gram-positive bacteria, however, its mode of action is still unclear. Reporter gene assays and proteomic profiling experiments in Bacillus subtilis indicate that Rom does not address classical antibiotic targets like translation, transcription or DNA replication, but acts at the cytoplasmic membrane. In Staphylococcus aureus, Rom decreases the membrane potential within seconds and at low doses, causes release of ATP and even the excretion of cytoplasmic proteins (ECP), but does not induce pore-formation as for example nisin. Lipid staining revealed that Rom induces local membrane damage. Rom's antimicrobial activity can be antagonized in the presence of a very narrow spectrum of saturated fatty acids (C15:0, C16:0, or C18:0) that most likely contribute to counteract the membrane damage. Gram-negative bacteria are resistant to Rom, presumably due to reduced penetration through the outer membrane and its neutralization by LPS. Rom is cytotoxic for many eukaryotic cells and studies with human erythrocytes showed that Rom induces eryptosis accompanied by erythrocyte shrinkage, cell membrane blebbing, and membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Rom's distinctive interaction with the cytoplasmic membrane reminds on the amphipathic, alpha-helical peptides, the phenol-soluble modulins (PSMs), and renders Rom an important tool for the investigation of membrane physiology.
Assuntos
Anti-Infecciosos/farmacologia , Membranas/efeitos dos fármacos , Xantonas/farmacologia , Animais , Células 3T3 BALB , Bacillus subtilis , Células Cultivadas , Células HeLa , Hemólise/efeitos dos fármacos , Humanos , Potenciais da Membrana/efeitos dos fármacos , Membranas/fisiologia , Camundongos , Testes de Sensibilidade Microbiana , Staphylococcus aureusRESUMO
Most Staphylococcus aureus strains secrete two lipases SAL1 and SAL2 encoded by gehA and gehB. These two lipases differ with respect to their substrate specificity. Staphylococcus hyicus secretes another lipase, SHL, which is in contrast to S. aureus lipases Ca2+-dependent and has a broad-spectrum lipase and phospholipase activity. The aim of this study was to investigate the role of staphylococcal (phospho) lipases in virulence. For this we constructed a gehA-gehB double deletion mutant in S. aureus USA300 and expressed SHL in agr-positive (accessory gene regulator) and agr-negative S. aureus strains. The lipases themselves have no hemolytic or cytotoxic activity. However, in agr-negative strains SHL-expression caused an upregulation of hemolytic activity. We further show that SHL-expression significantly enhanced biofilm formation probably due to an increase of extracellular DNA release. SHL-expression also increased host cell invasion 4-6-fold. Trioleate, a main triacylglycerol component of mammalian skin, induced lipase production. Finally, in the mouse sepsis and skin colonization models the lipase producing and mutant strain showed no significant difference compared to the WT strain. In conclusion, we show that staphylococcal lipases promote biofilm formation and host cell invasion and thereby contribute to S. aureus virulence.
Assuntos
Proteínas de Bactérias/genética , Biofilmes/crescimento & desenvolvimento , Fosfolipases/genética , Staphylococcus/enzimologia , Staphylococcus/patogenicidade , Animais , Modelos Animais de Doenças , Hemólise , Interações Hospedeiro-Patógeno , Camundongos , Mutação , Pele/microbiologia , Infecções Estafilocócicas/sangue , Staphylococcus/genética , Trioleína/farmacologia , VirulênciaRESUMO
Inherited monogenic disease has an enormous impact on the well-being of children and their families. Over half of the children living with one of these conditions are without a molecular diagnosis because of the rarity of the disease, the marked clinical heterogeneity, and the reality that there are thousands of rare diseases for which causative mutations have yet to be identified. It is in this context that in 2010 a Canadian consortium was formed to rapidly identify mutations causing a wide spectrum of pediatric-onset rare diseases by using whole-exome sequencing. The FORGE (Finding of Rare Disease Genes) Canada Consortium brought together clinicians and scientists from 21 genetics centers and three science and technology innovation centers from across Canada. From nation-wide requests for proposals, 264 disorders were selected for study from the 371 submitted; disease-causing variants (including in 67 genes not previously associated with human disease; 41 of these have been genetically or functionally validated, and 26 are currently under study) were identified for 146 disorders over a 2-year period. Here, we present our experience with four strategies employed for gene discovery and discuss FORGE's impact in a number of realms, from clinical diagnostics to the broadening of the phenotypic spectrum of many diseases to the biological insight gained into both disease states and normal human development. Lastly, on the basis of this experience, we discuss the way forward for rare-disease genetic discovery both in Canada and internationally.
Assuntos
Estudos de Associação Genética/métodos , Doenças Raras/diagnóstico , Doenças Raras/genética , Sociedades Científicas/organização & administração , Canadá , Humanos , Mutação , FenótipoRESUMO
BACKGROUND/AIMS: Consequences of bacterial infection include anemia, which could result from stimulation of suicidal erythrocyte death or eryptosis, characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Bacterial components known to stimulate eryptosis include lipopeptides. Signaling mediating the triggering of eryptosis include increased cytosolic Ca2+ activity ([Ca2+]i), oxidative stress and cellular accumulation of ceramide. The present study aimed to define the molecular requirements for lipopeptide-induced cell membrane scrambling. METHODS: Human erythrocytes were incubated for 48 hours in the absence and presence of 1 or 5 µg/ml of the synthetic lipopeptides Pam1 (lipopeptide with one fatty acid), Pam2 (lipopeptide with two fatty acids), or Pam3 (lipopeptide with three fatty acids). In the following phosphatidylserine exposure at the cell surface was estimated from annexin-V-binding, cell volume from forward scatter, [Ca2+]i from Fluo3-fluorescence, ROS formation from DCF dependent fuorescence, and ceramide abundance utilizing specific antibodies. RESULTS: Pam1 (5 µg/ml), Pam2 (5 µg/ml) and Pam3 (1 and 5 µg/ml) significantly increased the percentage of annexin-V-binding to erythrocytes in a dose dependent manner, which was largely independent of Ca2+. Pam1-3 increased the percentage of both, swollen and shrunken erythrocytes without significantly modifying the average forward scatter. They also increased reactive oxygen species (ROS) and ceramide abundance. In all assays the effect on eryptosis increased with increasing number of fatty acids, with Pam3 showing always the strongest effect. In contrast, a comparison of the effect of Pam1-3 on TLR2 dependent immune stimulation showed that not Pam3 but Pam2 displayed the strongest activity, and that immune stimulation was triggered at much lower concentrations than eryptosis. CONCLUSIONS: Lipopeptides are not only important activators of the immune system; at higher concentrations they also drive host cells into apoptosis thus aggravating a bacterial infection.
Assuntos
Eriptose/efeitos dos fármacos , Lipopeptídeos/toxicidade , Acilação , Sequência de Aminoácidos , Cálcio/metabolismo , Tamanho Celular/efeitos dos fármacos , Ceramidas/metabolismo , Membrana Eritrocítica/efeitos dos fármacos , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Células HEK293 , Humanos , Lipopeptídeos/química , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilserinas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismoRESUMO
All Staphylococcus aureus genomes contain a genomic island, which is termed νSaα and characterized by two clusters of tandem repeat sequences, i.e. the exotoxin (set) and 'lipoprotein-like' genes (lpl). Based on their structural similarities the νSaα islands have been classified as type I to IV. The genomes of highly pathogenic and particularly epidemic S. aureus strains (USA300, N315, Mu50, NCTC8325, Newman, COL, JH1 or JH9) belonging to the clonal complexes CC5 and CC8 bear a type I νSaα island. Since the contribution of the lpl gene cluster encoded in the νSaα island to virulence is unclear to date, we deleted the entire lpl gene cluster in S. aureus USA300. The results showed that the mutant was deficient in the stimulation of pro-inflammatory cytokines in human monocytes, macrophages and keratinocytes. Purified lipoprotein Lpl1 was further shown to elicit a TLR2-dependent response. Furthermore, heterologous expression of the USA300 lpl cluster in other S. aureus strains enhanced their immune stimulatory activity. Most importantly, the lpl cluster contributed to invasion of S. aureus into human keratinocytes and mouse skin and the non-invasive S. carnosus expressing the lpl gene cluster became invasive. Additionally, in a murine kidney abscess model the bacterial burden in the kidneys was higher in wild type than in mutant mice. In this infection model the lpl cluster, thus, contributes to virulence. The present report is one of the first studies addressing the role of the νSaα encoded lpl gene cluster in staphylococcal virulence. The finding that the lpl gene cluster contributes to internalization into non-professional antigen presenting cells such as keratinocytes highlights the lpl as a new cell surface component that triggers host cell invasion by S. aureus. Increased invasion in murine skin and an increased bacterial burden in a murine kidney abscess model suggest that the lpl gene cluster serves as an important virulence factor.
Assuntos
Ilhas Genômicas/genética , Infecções Estafilocócicas/genética , Staphylococcus aureus/genética , Staphylococcus aureus/patogenicidade , Virulência/genética , Animais , Células Cultivadas , DNA Bacteriano/genética , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Técnicas de Inativação de Genes , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Fatores de Virulência/genéticaRESUMO
Since the 1950s, Staphylococcus carnosus is used as a starter culture for sausage fermentation where it contributes to food safety, flavor, and a controlled fermentation process. The long experience with S. carnosus has shown that it is a harmless and "food grade" species. This was confirmed by the genome sequence of S. carnosus TM300 that lacks genes involved in pathogenicity. Since the development of a cloning system in TM300, numerous genes have been cloned, expressed, and characterized and in particular, virulence genes that could be functionally validated in this non-pathogenic strain. A secretion system was developed for production and secretion of industrially important proteins and later modified to also enable display of heterologous proteins on the surface. The display system has been employed for various purposes, such as development of live bacterial delivery vehicles as well as microbial biocatalysts or bioadsorbents for potential environmental or biosensor applications. Recently, this surface display system has been utilized for display of peptide and protein libraries for profiling of protease substrates and for generation of various affinity proteins, e.g., Affibody molecules and scFv antibodies. In addition, by display of fragmented antigen-encoding genes, the surface expression system has been successfully used for epitope mapping of antibodies. Reviews on specific applications of S. carnosus have been published earlier, but here we provide a more extensive overview, covering a broad range of areas from food fermentation to sophisticated methods for protein-based drug discovery, which are all based on S. carnosus.
Assuntos
Microbiologia de Alimentos/métodos , Engenharia de Proteínas/métodos , Staphylococcus/genética , Staphylococcus/metabolismo , Biotecnologia/métodos , Técnicas de Visualização da Superfície Celular/métodos , Fermentação , Staphylococcus/crescimento & desenvolvimentoRESUMO
Antimicrobial fatty acids (AFAs) protect the human epidermis against invasion by pathogenic bacteria. In this study, we questioned whether human skin fatty acids (FAs) can be incorporated into the lipid moiety of lipoproteins and whether such incorporation would have an impact on innate immune stimulation in the model organism Staphylococcus aureus USA300 JE2. This organism synthesized only saturated FAs. However, when feeding USA300 with unsaturated FAs present on human skin (C16:1, C18:1, or C18:2), those were taken up, elongated stepwise by two carbon units, and finally found in the bacterial (phospho)lipid fraction. They were also observed in the lipid moiety of lipoproteins. When USA300 JE2 was fed with the unsaturated FAs, the cells and cell lysates showed an increased innate immune activation with various immune cells and peripheral blood mononuclear cells (PBMCs). Immune activation was highest with linoleic acid (C18:2). There are several pieces of evidence that the enhanced immune stimulating effect was due to the incorporation of unsaturated FAs in lipoproteins. First, the enhanced stimulation was dependent on Toll-like receptor 2 (TLR2). Second, an lgt mutant, unable to carry out lipidation of prolipoproteins, was unable to carry out immune stimulation when fed with unsaturated FAs. Third, the supplied FAs did not significantly affect growth, protein release, or expression of the model lipoprotein Lpl1. Although S. aureus is unable to synthesize unsaturated FAs, it incorporates long-chain unsaturated FAs into its lipoproteins, with the effect that the cells are better recognized by the innate immune system. This is an additional mechanism how our skin controls bacterial colonization and infection.
Assuntos
Membrana Celular/metabolismo , Ácidos Graxos Insaturados/imunologia , Ácidos Graxos Insaturados/metabolismo , Pele/imunologia , Staphylococcus aureus/imunologia , Linhagem Celular Tumoral , Humanos , Imunidade Inata/imunologia , Leucócitos Mononucleares/imunologia , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/microbiologia , Receptor 2 Toll-Like , Transferases/genética , Transferases/metabolismoRESUMO
Excretion of cytoplasmic proteins in pro- and eukaryotes, also referred to as "nonclassical protein export," is a well-known phenomenon. However, comparatively little is known about the role of the excreted proteins in relation to pathogenicity. Here, the impact of two excreted glycolytic enzymes, aldolase (FbaA) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH), on pathogenicity was investigated in Staphylococcus aureus Both enzymes bound to certain host matrix proteins and enhanced adherence of the bacterial cells to host cells but caused a decrease in host cell invasion. FbaA and GAPDH also bound to the cell surfaces of staphylococcal cells by interaction with the major autolysin, Atl, that is involved in host cell internalization. Surprisingly, FbaA showed high cytotoxicity to both MonoMac 6 (MM6) and HaCaT cells, while GAPDH was cytotoxic only for MM6 cells. Finally, the contribution of external FbaA and GAPDH to S. aureus pathogenicity was confirmed in an insect infection model.
Assuntos
Adesinas Bacterianas/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/metabolismo , Interações Hospedeiro-Patógeno , N-Acetil-Muramil-L-Alanina Amidase/metabolismo , Staphylococcus aureus/patogenicidade , Adesinas Bacterianas/genética , Adesinas Bacterianas/toxicidade , Animais , Aderência Bacteriana , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Proteínas da Matriz Extracelular/genética , Regulação da Expressão Gênica , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/genética , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/toxicidade , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Queratinócitos/microbiologia , Larva/microbiologia , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Leucócitos/microbiologia , Mariposas/microbiologia , N-Acetil-Muramil-L-Alanina Amidase/genética , Ligação Proteica , Transdução de Sinais , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo , Análise de Sobrevida , VirulênciaRESUMO
Agents capable of eradicating bacterial biofilms are of great importance to human health as biofilm-associated infections are tolerant to our current antibiotic therapies. We have recently discovered that halogenated quinoline (HQ) small molecules are: 1)â capable of eradicating methicillin-resistant Staphylococcus aureus (MRSA), methicillin-resistant Staphylococcus epidermidis (MRSE) and vancomycin-resistant Enterococcus faecium (VRE) biofilms, and 2)â synthetic tuning of the 2-position of the HQ scaffold has a significant impact on antibacterial and antibiofilm activities. Here, we report the chemical synthesis and biological evaluation of 39 HQ analogues that have a high degree of structural diversity at the 2-position. We identified diverse analogues that are alkylated and aminated at the 2-position of the HQ scaffold and demonstrate potent antibacterial (MIC≤0.39â µm) and biofilm eradication (MBEC 1.0-93.8â µm) activities against drug-resistant Staphylococcus aureus, Staphylococcus epidermidis and Enterococcus faecium strains while demonstrating <5 % haemolysis activity against human red blood cells (RBCs) at 200â µm. In addition, these HQs demonstrated low cytotoxicity against HeLa cells. Halogenated quinolines are a promising class of antibiofilm agents against Gram-positive pathogens that could lead to useful treatments against persistent bacterial infections.
Assuntos
Antibacterianos/síntese química , Quinolinas/química , Alquilação , Aminação , Antibacterianos/farmacologia , Antibacterianos/toxicidade , Biofilmes/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Farmacorresistência Bacteriana/efeitos dos fármacos , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/fisiologia , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Halogenação , Células HeLa , Hemólise/efeitos dos fármacos , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/fisiologia , Quinolinas/farmacologia , Quinolinas/toxicidade , Staphylococcus/efeitos dos fármacos , Relação Estrutura-AtividadeRESUMO
PURPOSE: This article proposes recommendations for the use of whole-genome and whole-exome (WGS/WES) sequencing in clinical practice, endorsed by the board of directors of the Canadian College of Medical Geneticists. The publication of statements and recommendations by several international and national organisations on clinical WGS/WES has prompted a need for Canadian-specific guidance. METHODS: A multi-disciplinary group consisting of lawyers, ethicists, genetic researchers, and clinical geneticists was assembled to review existing guidelines on WGS/WES and identify provisions relevant to the Canadian context. RESULTS: Definitions were provided to orient the recommendations and to minimize confusion with other recommendations. Recommendations include the following: WGS/WES should be used in a judicious and cost-efficient manner; WGS/WES should be used to answer a clinical question; and physicians need to explain to adult patients the nature of the results that could arise, so as to allow them to make informed choices over whether to take the test and which results they wish to receive. Recommendations are also provided for WGS/WES in the pediatric context, and for when results implicate patients' family members. CONCLUSION: These recommendations are only a proposal to be developed into comprehensive Canadian-based guidelines. They aim to promote discussion about the reporting of WGS/WES results, and to encourage the ethical implementation of these new technologies in the clinical setting.
Assuntos
Exoma , Genética Médica , Genoma Humano , Sequenciamento de Nucleotídeos em Larga Escala , Guias de Prática Clínica como Assunto , Canadá , Genética Médica/métodos , Genética Médica/normas , HumanosRESUMO
Gallstone (GS) disease is common and arises from a combination of genetic and environmental factors. Although genetic abnormalities specifically leading to cholesterol GSs are rare, there are clinically significant gene variants associated with cholesterol GSs. In contrast, most bilirubin GSs can be attributed to genetic defects. The pathogenesis of cholesterol and bilirubin GSs differs greatly. Cholesterol GSs are notably influenced by genetic variants within the ABC protein superfamily, including ABCG8, ABCG5, ABCB4, and ABCB11, as well as genes from the apolipoprotein family such as ApoB100 and ApoE (especially the E3/E3 and E3/E4 variants), and members of the MUC family. Conversely, bilirubin GSs are associated with genetic variants in highly expressed hepatic genes, notably UGT1A1, ABCC2 (MRP2), ABCC3 (MRP3), CFTR, and MUC, alongside genetic defects linked to hemolytic anemias and conditions impacting erythropoiesis. While genetic cases constitute a small portion of GS disease, recognizing genetic predisposition is essential for proper diagnosis, treatment, and genetic counseling.