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Rationale: Chronic obstructive pulmonary disease (COPD) is a disease characterized by persistent airway inflammation and disordered macrophage function. The extent to which alterations in macrophage bioenergetics contribute to impaired antioxidant responses and disease pathogenesis has yet to be fully delineated. Objectives: Through the study of COPD alveolar macrophages (AMs) and peripheral monocyte-derived macrophages (MDMs), we sought to establish if intrinsic defects in core metabolic processes drive macrophage dysfunction and redox imbalance. Methods: AMs and MDMs from donors with COPD and healthy donors underwent functional, metabolic, and transcriptional profiling. Measurements and Main Results: We observed that AMs and MDMs from donors with COPD display a critical depletion in glycolytic- and mitochondrial respiration-derived energy reserves and an overreliance on glycolysis as a source for ATP, resulting in reduced energy status. Defects in oxidative metabolism extend to an impaired redox balance associated with defective expression of the NADPH-generating enzyme, ME1 (malic enzyme 1), a known target of the antioxidant transcription factor NRF2 (nuclear factor erythroid 2-related factor 2). Consequently, selective activation of NRF2 resets the COPD transcriptome, resulting in increased generation of TCA cycle intermediaries, improved energetic status, favorable redox balance, and recovery of macrophage function. Conclusions: In COPD, an inherent loss of metabolic plasticity leads to metabolic exhaustion and reduced redox capacity, which can be rescued by activation of the NRF2 pathway. Targeting these defects, via NRF2 augmentation, may therefore present an attractive therapeutic strategy for the treatment of the aberrant airway inflammation described in COPD.
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Fator 2 Relacionado a NF-E2 , Doença Pulmonar Obstrutiva Crônica , Humanos , Macrófagos/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Malato Desidrogenase/metabolismoRESUMO
MOTIVATION: A common experimental output in biomedical science is a list of genes implicated in a given biological process or disease. The gene lists resulting from a group of studies answering the same, or similar, questions can be combined by ranking aggregation methods to find a consensus or a more reliable answer. Evaluating a ranking aggregation method on a specific type of data before using it is required to support the reliability since the property of a dataset can influence the performance of an algorithm. Such evaluation on gene lists is usually based on a simulated database because of the lack of a known truth for real data. However, simulated datasets tend to be too small compared to experimental data and neglect key features, including heterogeneity of quality, relevance and the inclusion of unranked lists. RESULTS: In this study, a group of existing methods and their variations that are suitable for meta-analysis of gene lists are compared using simulated and real data. Simulated data were used to explore the performance of the aggregation methods as a function of emulating the common scenarios of real genomic data, with various heterogeneity of quality, noise level and a mix of unranked and ranked data using 20 000 possible entities. In addition to the evaluation with simulated data, a comparison using real genomic data on the SARS-CoV-2 virus, cancer (non-small cell lung cancer) and bacteria (macrophage apoptosis) was performed. We summarize the results of our evaluation in a simple flowchart to select a ranking aggregation method, and in an automated implementation using the meta-analysis by information content algorithm to infer heterogeneity of data quality across input datasets. AVAILABILITY AND IMPLEMENTATION: The code for simulated data generation and running edited version of algorithms: https://github.com/baillielab/comparison_of_RA_methods. Code to perform an optimal selection of methods based on the results of this review, using the MAIC algorithm to infer the characteristics of an input dataset, can be downloaded here: https://github.com/baillielab/maic. An online service for running MAIC: https://baillielab.net/maic. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.
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COVID-19 , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Algoritmos , Carcinoma Pulmonar de Células não Pequenas/genética , COVID-19/genética , Neoplasias Pulmonares/genética , Reprodutibilidade dos Testes , SARS-CoV-2 , Metanálise como AssuntoRESUMO
Acute kidney injury (AKI) is a prevalent complication in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) positive inpatients, which is linked to an increased mortality rate compared to patients without AKI. Here we analysed the difference in kidney blood biomarkers in SARS-CoV-2 positive patients with non-fatal or fatal outcome, in order to develop a mortality prediction model for hospitalised SARS-CoV-2 positive patients. A retrospective cohort study including data from suspected SARS-CoV-2 positive patients admitted to a large National Health Service (NHS) Foundation Trust hospital in the Yorkshire and Humber regions, United Kingdom, between 1 March 2020 and 30 August 2020. Hospitalised adult patients (aged ≥ 18 years) with at least one confirmed positive RT-PCR test for SARS-CoV-2 and blood tests of kidney biomarkers within 36 h of the RT-PCR test were included. The main outcome measure was 90-day in-hospital mortality in SARS-CoV-2 infected patients. The logistic regression and random forest (RF) models incorporated six predictors including three routine kidney function tests (sodium, urea; creatinine only in RF), along with age, sex, and ethnicity. The mortality prediction performance of the logistic regression model achieved an area under receiver operating characteristic (AUROC) curve of 0.772 in the test dataset (95% CI: 0.694-0.823), while the RF model attained the AUROC of 0.820 in the same test cohort (95% CI: 0.740-0.870). The resulting validated prediction model is the first to focus on kidney biomarkers specifically on in-hospital mortality over a 90-day period.
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Injúria Renal Aguda , COVID-19 , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/etiologia , Adulto , Biomarcadores , COVID-19/diagnóstico , Mortalidade Hospitalar , Humanos , Rim , Estudos Retrospectivos , SARS-CoV-2 , Medicina EstatalRESUMO
RATIONALE: Histone post-translational modifications (PTMs) play key roles in regulating eukaryotic gene expression. Mass spectrometry (MS) has emerged as a powerful method to characterize and quantify histone PTMs as it allows unbiased identification and quantification of multiple histone PTMs including combinations of the modifications present. METHODS: In this study we compared a range of data-acquisition methods for the identification and quantification of the histone PTMs using a Q Exactive HF Orbitrap. We compared three different data-dependent analysis (DDA) methods with MS2 resolutions of 120K, 60K, 30K. We also compared a range of data-independent analysis (DIA) methods using MS2 isolation windows of 20 m/z and DIAvw to identify and quantify histone PTMs in Chinese hamster ovary (CHO) cells. RESULTS: The increased number of MS2 scans afforded by the lower resolution methods resulted in a higher number of queries, peptide sequence matches (PSMs) and a higher number of peptide proteoforms identified with a Mascot Ion score greater than 46. No difference in the proportion of peptide proteoforms with Delta scores >17 was observed. Lower coefficients of variation (CVs) were obtained in the DIA MS1 60 K MS2 30 K 20 m/z isolation windows compared with the other data-acquisition methods. CONCLUSIONS: We observed that DIA which offers advantages in flexibility and identification of isobaric peptide proteoforms performs as well as DDA in the analysis of histone PTMs. We were able to identify 71 modified histone peptides for histone H3 and H4 and quantified 64 across each of the different acquisition methods.
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Histonas/química , Espectrometria de Massas/métodos , Animais , Células CHO , Cricetinae , Cricetulus , Humanos , Espectrometria de Massas/instrumentação , Peso Molecular , Peptídeos/química , Processamento de Proteína Pós-TraducionalRESUMO
RATIONALE: Previous studies have identified defects in bacterial phagocytosis by alveolar macrophages (AMs) in patients with chronic obstructive pulmonary disease (COPD), but the mechanisms and clinical consequences remain incompletely defined. OBJECTIVES: To examine the effect of COPD on AM phagocytic responses and identify the mechanisms, clinical consequences, and potential for therapeutic manipulation of these defects. METHODS: We isolated AMs and monocyte-derived macrophages (MDMs) from a cohort of patients with COPD and control subjects within the Medical Research Council COPDMAP consortium and measured phagocytosis of bacteria in relation to opsonic conditions and clinical features. MEASUREMENTS AND MAIN RESULTS: COPD AMs and MDMs have impaired phagocytosis of Streptococcus pneumoniae. COPD AMs have a selective defect in uptake of opsonized bacteria, despite the presence of antipneumococcal antibodies in BAL, not observed in MDMs or healthy donor AMs. AM defects in phagocytosis in COPD are significantly associated with exacerbation frequency, isolation of pathogenic bacteria, and health-related quality-of-life scores. Bacterial binding and initial intracellular killing of opsonized bacteria in COPD AMs was not reduced. COPD AMs have reduced transcriptional responses to opsonized bacteria, such as cellular stress responses that include transcriptional modules involving antioxidant defenses and Nrf2 (nuclear factor erythroid 2-related factor 2)-regulated genes. Agonists of the cytoprotective transcription factor Nrf2 (sulforaphane and compound 7) reverse defects in phagocytosis of S. pneumoniae and nontypeable Haemophilus influenzae by COPD AMs. CONCLUSIONS: Patients with COPD have clinically relevant defects in opsonic phagocytosis by AMs, associated with impaired transcriptional responses to cellular stress, which are reversed by therapeutic targeting with Nrf2 agonists.
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Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Fagocitose/efeitos dos fármacos , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Isotiocianatos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/fisiologia , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/fisiologia , Masculino , Pessoa de Meia-Idade , Fagocitose/fisiologia , Streptococcus pneumoniae , SulfóxidosRESUMO
We evaluated the effectiveness and safety of continuous antimicrobial infusion using a disposable elastomeric device in an outpatient parenteral antimicrobial therapy (OPAT) setting. We conducted a retrospective analysis of all patients who received either flucloxacillin (n = 131 episodes) or piperacillin/tazobactam (n = 301 episodes) as continuous infusion via elastomeric devices over 5 years (January 2018-December 2022) at a tertiary referral hospital in Derbyshire, UK. Overall, 81 adverse events were recorded in 77 (18%; 77/432) patient-episodes. Most adverse events were vascular access-related (59%; 4.6 events per 1000 OPAT-days), including one line-related infection (0.2%; 0.1 events per 1000 OPAT-days). 165 (38%) patient-episodes experienced at least one incident of incomplete infusion. Successful outcome (cure or improvement) occurred in 364 (84%) episodes. Our findings suggest that elastomeric infusion pumps are safe and effective for administering selected antimicrobial agents in OPAT. However, close monitoring of patients and the device are essential to ensure optimal delivery of prescribed therapy.
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Antibacterianos , Anti-Infecciosos , Humanos , Antibacterianos/uso terapêutico , Pacientes Ambulatoriais , Estudos Retrospectivos , Bombas de Infusão , Reino Unido , Assistência Ambulatorial , Infusões ParenteraisRESUMO
The risk of venous thromboembolism (VTE) in outpatient parenteral antimicrobial therapy (OPAT) is not fully understood and the optimal strategy for thromboprophylaxis remains unclear. This systematic review investigated the incidence of VTE in OPAT settings (PROSPERO CRD42022381523). MEDLINE, CINAHL, Emcare, Embase, Cochrane Library and grey literature were searched from earliest records to 18 January 2023. Primary studies reporting non-catheter-related VTE or catheter-related thromboembolism (CRT) events in adults who received parenteral antibiotics in home or outpatient settings were eligible. In total, 43 studies involving 23 432 patient episodes were reviewed, of which 4 studies reported non-catheter-related VTE and 39 included CRT. Based on generalised linear mixed-effects models, pooled risk estimates of non-catheter-related VTE and CRT were 0.2% [95% confidence interval (CI) 0.0-0.7%] and 1.1% [95% CI 0.8-1.5%; prediction interval (PI) 0.2-5.4%]. Heterogeneity was largely attributed to risk of bias by meta-regression (R2 = 21%). Excluding high-risk-of-bias studies, CRT risk was 0.8% (95% CI 0.5-1.2%; PI 0.1-4.5%). From 25 studies, the pooled CRT rate per 1000 catheter-days was 0.37 (95% CI 0.25-0.55; PI 0.08-1.64). These findings do not support universal thromboprophylaxis or routine use of an inpatient VTE risk assessment model in the OPAT setting. However, a high index of suspicion should be maintained, especially for patients with known risk factors for VTE. An optimised protocol of OPAT-specific VTE risk assessment should be sought.
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Anti-Infecciosos , Tromboembolia Venosa , Adulto , Humanos , Tromboembolia Venosa/tratamento farmacológico , Tromboembolia Venosa/prevenção & controle , Tromboembolia Venosa/epidemiologia , Anticoagulantes/uso terapêutico , Pacientes Ambulatoriais , Fatores de Risco , Anti-Infecciosos/efeitos adversosRESUMO
The 2022 monkeypox outbreak has affected 110 countries worldwide, outside of classic endemic areas (ie, west Africa and central Africa). On July 23, 2022, the outbreak was classified by WHO as a public health emergency of international concern. Clinical presentation varies from mild to life-changing symptoms; neurological complications are relatively uncommon and there are few therapeutic interventions for monkeypox disease. In this Grand Round, we present a case of monkeypox with encephalitis complicated by transverse myelitis in a previously healthy woman aged 35 years who made an almost complete recovery from her neurological symptoms after treatment with tecovirimat, cidofovir, steroids, and plasma exchange. We describe neurological complications associated with orthopoxvirus infections and laboratory diagnosis, the radiological features in this case, and discuss treatment options.
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Encefalite , Mpox , Mielite Transversa , Feminino , Humanos , África Ocidental , BenzamidasRESUMO
Previous studies have associated COVID-19 symptoms severity with levels of physical activity. We therefore investigated longitudinal trajectories of COVID-19 symptoms in a cohort of healthcare workers (HCWs) with non-hospitalised COVID-19 and their real-world physical activity. 121 HCWs with a history of COVID-19 infection who had symptoms monitored through at least two research clinic visits, and via smartphone were examined. HCWs with a compatible smartphone were provided with an Apple Watch Series 4 and were asked to install the MyHeart Counts Study App to collect COVID-19 symptom data and multiple physical activity parameters. Unsupervised classification analysis of symptoms identified two trajectory patterns of long and short symptom duration. The prevalence for longitudinal persistence of any COVID-19 symptom was 36% with fatigue and loss of smell being the two most prevalent individual symptom trajectories (24.8% and 21.5%, respectively). 8 physical activity features obtained via the MyHeart Counts App identified two groups of trajectories for high and low activity. Of these 8 parameters only 'distance moved walking or running' was associated with COVID-19 symptom trajectories. We report a high prevalence of long-term symptoms of COVID-19 in a non-hospitalised cohort of HCWs, a method to identify physical activity trends, and investigate their association. These data highlight the importance of tracking symptoms from onset to recovery even in non-hospitalised COVID-19 individuals. The increasing ease in collecting real-world physical activity data non-invasively from wearable devices provides opportunity to investigate the association of physical activity to symptoms of COVID-19 and other cardio-respiratory diseases.
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BACKGROUND: The scale of the 2022 global mpox (formerly known as monkeypox) outbreak has been unprecedented. In less than 6 months, non-endemic countries have reported more than 67 000 cases of a disease that had previously been rare outside of Africa. Mortality has been reported as rare but hospital admission has been relatively common. We aimed to describe the clinical and laboratory characteristics and outcomes of individuals admitted to hospital with mpox and associated complications, including tecovirimat recipients. METHODS: In this cohort study, we undertook retrospective review of electronic clinical records and pathology data for all individuals admitted between May 6, and Aug 3, 2022, to 16 hospitals from the Specialist and High Consequence Infectious Diseases Network for Monkeypox. The hospitals were located in ten cities in England and Northern Ireland. Inclusion criteria were clinical signs consistent with mpox and MPXV DNA detected from at least one clinical sample by PCR testing. Patients admitted solely for isolation purposes were excluded from the study. Key outcomes included admission indication, complications (including pain, secondary infection, and mortality) and use of antibiotic and anti-viral treatments. Routine biochemistry, haematology, microbiology, and virology data were also collected. Outcomes were assessed in all patients with available data. FINDINGS: 156 individuals were admitted to hospital with complicated mpox during the study period. 153 (98%) were male and three (2%) were female, with a median age of 35 years (IQR 30-44). Gender data were collected from electronic patient records, which encompassed full formal review of clincian notes. The prespecified options for data collection for gender were male, female, trans, non-binary, or unknown. 105 (71%) of 148 participants with available ethnicity data were of White ethnicity and 47 (30%) of 155 were living with HIV with a median CD4 count of 510 cells per mm3 (IQR 349-828). Rectal or perianal pain (including proctitis) was the most common indication for hospital admission (44 [28%] of 156). Severe pain was reported in 89 (57%) of 156, and secondary bacterial infection in 82 (58%) of 142 individuals with available data. Median admission duration was 5 days (IQR 2-9). Ten individuals required surgery and two cases of encephalitis were reported. 38 (24%) of the 156 individuals received tecovirimat with early cessation in four cases (two owing to hepatic transaminitis, one to rapid treatment response, and one to patient choice). No deaths occurred during the study period. INTERPRETATION: Although life-threatening mpox appears rare in hospitalised populations during the current outbreak, severe mpox and associated complications can occur in immunocompetent individuals. Analgesia and management of superimposed bacterial infection are priorities for patients admitted to hospital. FUNDING: None.
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Mpox , Humanos , Feminino , Masculino , Adulto , Estudos Retrospectivos , Estudos de Coortes , Hospitais , Dor , Benzamidas , Reino Unido/epidemiologiaRESUMO
Neisseria gonorrhoeae is an obligate human pathogen that is the cause of the sexually transmitted disease gonorrhoea. Recently, there has been a surge in gonorrhoea cases that has been exacerbated by the rapid rise in gonococcal multidrug resistance to all useful antimicrobials resulting in this organism becoming a significant public health burden. Therefore, there is a clear and present need to understand the organism's biology through its physiology and pathogenesis to help develop new intervention strategies. The gonococcus initially colonises and adheres to host mucosal surfaces utilising a type IV pilus that helps with microcolony formation. Other adhesion strategies include the porin, PorB, and the phase variable outer membrane protein Opa. The gonococcus is able to subvert complement mediated killing and opsonisation by sialylation of its lipooligosaccharide and deploys a series of anti-phagocytic mechanisms. N. gonorrhoeae is a fastidious organism that is able to grow on a limited number of primary carbon sources such as glucose and lactate. The utilization of lactate by the gonococcus has been implicated in a number of pathogenicity mechanisms. The bacterium lives mainly in microaerobic environments and can grow both aerobically and anaerobically with the aid of nitrite. The gonococcus does not produce siderophores for scavenging iron but can utilize some produced by other bacteria, and it is able to successful chelate iron from host haem, transferrin and lactoferrin. The gonococcus is an incredibly versatile human pathogen; in the following chapter, we detail the intricate mechanisms used by the bacterium to invade and survive within the host.
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Gonorreia , Neisseria gonorrhoeae , Gonorreia/microbiologia , Humanos , Ferro/metabolismo , Lactatos/metabolismo , Neisseria gonorrhoeae/metabolismo , VirulênciaRESUMO
There have been numerous risk tools developed to enable triaging of SARS-CoV-2 positive patients with diverse levels of complexity. Here we presented a simplified risk-tool based on minimal parameters and chest X-ray (CXR) image data that predicts the survival of adult SARS-CoV-2 positive patients at hospital admission. We analysed the NCCID database of patient blood variables and CXR images from 19 hospitals across the UK using multivariable logistic regression. The initial dataset was non-randomly split between development and internal validation dataset with 1434 and 310 SARS-CoV-2 positive patients, respectively. External validation of the final model was conducted on 741 Accident and Emergency (A&E) admissions with suspected SARS-CoV-2 infection from a separate NHS Trust. The LUCAS mortality score included five strongest predictors (Lymphocyte count, Urea, C-reactive protein, Age, Sex), which are available at any point of care with rapid turnaround of results. Our simple multivariable logistic model showed high discrimination for fatal outcome with the area under the receiving operating characteristics curve (AUC-ROC) in development cohort 0.765 (95% confidence interval (CI): 0.738-0.790), in internal validation cohort 0.744 (CI: 0.673-0.808), and in external validation cohort 0.752 (CI: 0.713-0.787). The discriminatory power of LUCAS increased slightly when including the CXR image data. LUCAS can be used to obtain valid predictions of mortality in patients within 60 days of SARS-CoV-2 RT-PCR results into low, moderate, high, or very high risk of fatality.
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COVID-19 , Adulto , Humanos , SARS-CoV-2 , Proteína C-Reativa/análise , Ureia , Raios X , Contagem de Linfócitos , Estudos RetrospectivosRESUMO
Background: COVID-19 medicines delivery units (CMDU) were established in late December 2021 to deliver early antiviral therapy to patients classified as at risk with the aim of preventing hospitalization. Methods: We performed a service evaluation at 4 CMDUs in England. We assessed demographics and triage outcomes of CMDU referral, uptake of antiviral therapy, and the rate of subsequent hospitalizations within 2 weeks of CMDU referral. Results: Over a 3-week period, 4788 patients were referred and 3989 were ultimately assessed by a CMDU. Overall, 832 of the patients referred (17%) were judged eligible for treatment and 628 (13%) were ultimately prescribed an antiviral agent. The overall rate of admission within 14â days was 1%. Patients who were admitted were significantly older than those who did not require hospitalization. Of patients prescribed molnupiravir and sotrovimab, 1.8% and 3.2%, respectively, were admitted. Conclusions: There was a high volume of referrals to CMDU service during the initial surge of the Omicron wave in the United Kingdom. A minority of patients were judged to be eligible for therapy. In a highly vaccinated population, the overall hospitalization rate was low.
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Background: Neutrophil extracellular traps (NETs) are web-like DNA and protein lattices which are expelled by neutrophils to trap and kill pathogens, but which cause significant damage to the host tissue. NETs have emerged as critical mediators of lung damage, inflammation and thrombosis in coronavirus disease 2019 (COVID-19) and other diseases, but there are no therapeutics to prevent or reduce NETs that are available to patients. Methods: Neutrophils were isolated from healthy volunteers (n=9) and hospitalised patients with COVID-19 at the acute stage (n=39) and again at 3-4â months post-acute sampling (n=7). NETosis was measured by SYTOX green assays. Results: Here, we show that neutrophils isolated from hospitalised patients with COVID-19 produce significantly more NETs in response to lipopolysaccharide (LPS) compared to cells from healthy control subjects. A subset of patients was captured at follow-up clinics (3-4â months post-acute sampling), and while LPS-induced NET formation is significantly lower at this time point, it remains elevated compared to healthy controls. LPS- and phorbol myristate acetate (PMA)-induced NETs were significantly inhibited by the protein kinase C (PKC) inhibitor ruboxistaurin. Ruboxistaurin-mediated inhibition of NETs in healthy neutrophils reduces NET-induced epithelial cell death. Conclusion: Our findings suggest ruboxistaurin could reduce proinflammatory and tissue-damaging consequences of neutrophils during disease, and since it has completed phase III trials for other indications without safety concerns, it is a promising and novel therapeutic strategy for COVID-19.
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This study aims to identify factors associated with duration of intravenous (IV) and follow-on oral antibiotic therapy for cellulitis in patients treated through outpatient parenteral antimicrobial therapy (OPAT). A retrospective review of episodes of cellulitis treated over a year (January 2018-January 2019) at a large teaching hospital in Sheffield, UK. Overall, 292 OPAT episodes of cellulitis were reviewed. The mean durations of IV therapy and follow-on oral antibiotics were 5.3 days (range 1-32 days) and 6.1 days (range 2-17 days), respectively. Age, peak C-reactive protein and frequency of medical assessments during OPAT were independently associated with longer duration of IV therapy. Senior clinicians were likely to prescribe shorter courses of follow-on oral antibiotics. IV to oral conversion was more likely to occur on the first day of the work week. Our findings suggest that clinical and OPAT-related factors can influence early conversion to oral antibiotic therapy.
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Anti-Infecciosos , Celulite (Flegmão)/tratamento farmacológico , Celulite (Flegmão)/epidemiologia , Administração Intravenosa , Administração Oral , Adulto , Idoso , Assistência Ambulatorial , Anti-Infecciosos/administração & dosagem , Anti-Infecciosos/uso terapêutico , Duração da Terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
Epigenetic modifications regulate gene expression in the host response to a diverse range of pathogens. The extent and consequences of epigenetic modification during macrophage responses to Streptococcus pneumoniae, and the role of pneumolysin, a key Streptococcus pneumoniae virulence factor, in influencing these responses, are currently unknown. To investigate this, we infected human monocyte derived macrophages (MDMs) with Streptococcus pneumoniae and addressed whether pneumolysin altered the epigenetic landscape and the associated acute macrophage transcriptional response using a combined transcriptomic and proteomic approach. Transcriptomic analysis identified 503 genes that were differentially expressed in a pneumolysin-dependent manner in these samples. Pathway analysis highlighted the involvement of transcriptional responses to core innate responses to pneumococci including modules associated with metabolic pathways activated in response to infection, oxidative stress responses and NFκB, NOD-like receptor and TNF signalling pathways. Quantitative proteomic analysis confirmed pneumolysin-regulated protein expression, early after bacterial challenge, in representative transcriptional modules associated with innate immune responses. In parallel, quantitative mass spectrometry identified global changes in the relative abundance of histone post translational modifications (PTMs) upon pneumococcal challenge. We identified an increase in the relative abundance of H3K4me1, H4K16ac and a decrease in H3K9me2 and H3K79me2 in a PLY-dependent fashion. We confirmed that pneumolysin blunted early transcriptional responses involving TNF-α and IL-6 expression. Vorinostat, a histone deacetylase inhibitor, similarly downregulated TNF-α production, reprising the pattern observed with pneumolysin. In conclusion, widespread changes in the macrophage transcriptional response are regulated by pneumolysin and are associated with global changes in histone PTMs. Modulating histone PTMs can reverse pneumolysin-associated transcriptional changes influencing innate immune responses, suggesting that epigenetic modification by pneumolysin plays a role in dampening the innate responses to pneumococci.
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Proteínas de Bactérias/metabolismo , Epigênese Genética , Perfilação da Expressão Gênica , Macrófagos/metabolismo , Streptococcus pneumoniae/metabolismo , Estreptolisinas/metabolismo , Proteínas de Bactérias/genética , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Histonas/metabolismo , Interações Hospedeiro-Patógeno , Humanos , Macrófagos/microbiologia , Metilação , Processamento de Proteína Pós-Traducional , Proteoma/metabolismo , Proteômica/métodos , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/fisiologia , Estreptolisinas/genéticaRESUMO
Staphylococcus aureus is a member of the human commensal microflora that exists, apparently benignly, at multiple sites on the host. However, as an opportunist pathogen it can also cause a range of serious diseases. This requires an ability to circumvent the innate immune system to establish an infection. Professional phagocytes, primarily macrophages and neutrophils, are key innate immune cells which interact with S. aureus, acting as gatekeepers to contain and resolve infection. Recent studies have highlighted the important roles of macrophages during S. aureus infections, using a wide array of killing mechanisms. In defense, S. aureus has evolved multiple strategies to survive within, manipulate and escape from macrophages, allowing them to not only subvert but also exploit this key element of our immune system. Macrophage-S. aureus interactions are multifaceted and have direct roles in infection outcome. In depth understanding of these host-pathogen interactions may be useful for future therapeutic developments. This review examines macrophage interactions with S. aureus throughout all stages of infection, with special emphasis on mechanisms that determine infection outcome.
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Interações Hospedeiro-Patógeno/imunologia , Macrófagos/imunologia , Infecções Estafilocócicas/imunologia , Staphylococcus aureus/imunologia , Animais , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/fisiologia , Vacinas Bacterianas , Cátions/metabolismo , Morte Celular , Quimiotaxia , Citocinas/metabolismo , Vesículas Extracelulares/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Evasão da Resposta Imune/imunologia , Macrófagos/classificação , Macrófagos/enzimologia , Macrófagos/microbiologia , Camundongos , Nutrientes/metabolismo , Fagocitose , Fagossomos/química , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptores de Complemento/fisiologia , Receptores Fc/imunologia , Receptores Depuradores/fisiologia , Staphylococcus aureus/efeitos dos fármacosRESUMO
BACKGROUND: Meningococcal disease occurs after colonization of the nasopharynx with Neisseria meningitidis. Surfactant protein (SP)-A and SP-D are pattern-recognition molecules of the respiratory tract that activate inflammatory and phagocytic defences after binding to microbial sugars. Variation in the genes of the surfactant proteins affects the expression and function of these molecules. METHODS: Allele frequencies of SP-A1, SP-A2, and SP-D were determined by polymerase chain reaction in 303 patients with microbiologically proven meningococcal disease, including 18 patients who died, and 222 healthy control subjects. RESULTS: Homozygosity of allele 1A1 of SP-A2 increased the risk of meningococcal disease (odds ratio [OR], 7.4; 95% confidence interval [CI], 1.3-42.4); carriage of 1A5 reduced the risk (OR, 0.3; 95% CI, 0.1-0.97). An analysis of the multiple single-nucleotide polymorphisms in SP-A demonstrated that homozygosity for alleles encoding lysine (in 1A1) rather than glutamine (in 1A5) at amino acid 223 in the carbohydrate recognition domain was associated with an increased risk of meningococcal disease (OR, 6.7; 95% CI, 1.4-31.5). Carriage of alleles encoding lysine at residue 223 was found in 61% of patients who died, compared with 35% of those who survived (OR adjusted for age, 2.9; 95% CI, 1.1-7.7). Genetic variation of SP-A1 and SP-D was not associated with meningococcal disease. CONCLUSIONS: Gene polymorphism resulting in the substitution of glutamine with lysine at residue 223 in the carbohydrate recognition domain of SP-A2 increases susceptibility to meningococcal disease, as well as the risk of death.
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Predisposição Genética para Doença , Infecções Meningocócicas/genética , Infecções Meningocócicas/metabolismo , Polimorfismo Genético , Proteína A Associada a Surfactante Pulmonar/genética , Adulto , Idoso , Alelos , Substituição de Aminoácidos , Sítios de Ligação , Estudos de Casos e Controles , Criança , Pré-Escolar , Haplótipos , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Razão de Chances , Estrutura Terciária de Proteína , Proteína D Associada a Surfactante Pulmonar/genéticaRESUMO
Epigenetic modifications are increasingly recognized as playing an important role in the pathogenesis of infectious diseases. They represent a critical mechanism regulating transcriptional profiles in the immune system that contributes to the cell-type and stimulus specificity of the transcriptional response. Recent data highlight how epigenetic changes impact macrophage functional responses and polarization, influencing the innate immune system through macrophage tolerance and training. In this review we will explore how post-translational modifications of histone tails influence immune function to specific infectious diseases. We will describe how these may influence outcome, highlighting examples derived from responses to acute bacterial pathogens, models of sepsis, maintenance of viral latency and HIV infection. We will discuss how emerging classes of pharmacological agents, developed for use in oncology and other settings, have been applied to models of infectious diseases and their potential to modulate key aspects of the immune response to bacterial infection and HIV therapy.