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1.
BMC Infect Dis ; 21(1): 814, 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34388972

RESUMO

BACKGROUND: SARS-CoV-2 infection rapidly spreads in populations due to the high rates of community transmission. Interrupting the shedding of SARS-CoV-2 may reduce the incidence of Coronavirus Disease 19 (COVID-19). Herein we provide a protocol for a cluster randomized trial that will examine the effectiveness of treatment with interferon (IFN) ß-1a compared to standard of care in limiting the transmission of SARS-CoV-2. Co-primary objectives are to determine whether IFN therapy reduces (a) the proportion of infected cases shedding SARS-CoV-2 at day 11 post randomization and (b) the incidence of transmission of SARS-CoV-2 infection from index cases to treatment-eligible household post-exposure contacts at day 11 after randomization. Secondary objectives include assessing the impact of IFN treatment on duration of viral clearance, hospitalizations and fatalities, and evaluating the safety of IFN treatment. METHODS: Three hundred and ten households, each including an index case with a recent COVID-19 diagnosis and at least one asymptomatic treatment-eligible household contact, will be randomized to receive 3 doses of 125 µg IFN ß-1a by subcutaneous administration (days 1, 6, and 11), or standard of care. All participants will be followed until day 29. DISCUSSION: The results from this trial will identify whether IFN ß treatment of mild or moderate COVID-19 cases accelerates viral clearance and prevents disease progression and whether IFN ß treatment of post-exposure contacts of COVID-19 cases reduces transmission of infection. TRIAL REGISTRATION: This trial is registered at ClinicalTrials.gov NCT04552379; date of registration September 17, 2020.


Assuntos
Antivirais/uso terapêutico , Tratamento Farmacológico da COVID-19 , Interferon beta/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , COVID-19/diagnóstico , COVID-19/transmissão , Teste para COVID-19 , Humanos , SARS-CoV-2 , Resultado do Tratamento
2.
PLoS Pathog ; 10(1): e1003901, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24497831

RESUMO

Leishmania parasites infect macrophages, cells that play an important role in organismal iron homeostasis. By expressing ferroportin, a membrane protein specialized in iron export, macrophages release iron stored intracellularly into the circulation. Iron is essential for the intracellular replication of Leishmania, but how the parasites compete with the iron export function of their host cell is unknown. Here, we show that infection with Leishmania amazonensis inhibits ferroportin expression in macrophages. In a TLR4-dependent manner, infected macrophages upregulated transcription of hepcidin, a peptide hormone that triggers ferroportin degradation. Parasite replication was inhibited in hepcidin-deficient macrophages and in wild type macrophages overexpressing mutant ferroportin that is resistant to hepcidin-induced degradation. Conversely, intracellular growth was enhanced by exogenously added hepcidin, or by expression of dominant-negative ferroportin. Importantly, dominant-negative ferroportin and macrophages from flatiron mice, a mouse model for human type IV hereditary hemochromatosis, restored the infectivity of mutant parasite strains defective in iron acquisition. Thus, inhibition of ferroportin expression is a specific strategy used by L. amazonensis to inhibit iron export and promote their own intracellular growth.


Assuntos
Ferro/metabolismo , Leishmania/metabolismo , Leishmaniose/metabolismo , Macrófagos/metabolismo , Animais , Transporte Biológico Ativo/genética , Proteínas de Transporte de Cátions/biossíntese , Proteínas de Transporte de Cátions/deficiência , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica/genética , Hemocromatose/genética , Hemocromatose/metabolismo , Hemocromatose/parasitologia , Hemocromatose/patologia , Hepcidinas/biossíntese , Hepcidinas/genética , Humanos , Leishmaniose/genética , Leishmaniose/patologia , Macrófagos/parasitologia , Macrófagos/patologia , Camundongos , Camundongos Knockout , Mutação
3.
BMC Genomics ; 14: 723, 2013 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-24148319

RESUMO

BACKGROUND: Leishmania are obligated intracellular pathogens that replicate almost exclusively in macrophages. The outcome of infection depends largely on parasite pathogenicity and virulence but also on the activation status and genetic background of macrophages. Animal models are essential for a better understanding of pathogenesis of different microbes including Leishmania. RESULTS: Here we compared the transcriptional signatures of resistant (C57BL/6) and susceptible (BALB/c) mouse bone marrow-derived macrophages in response to Leishmania major (L. major) promastigotes infection.Microarray results were first analyzed for significant pathways using the Kyoto Encylopedia of Genes and Genomes (KEGG) database. The analysis revealed that a large set of the shared genes is involved in the immune response and that difference in the expression level of some chemokines and chemokine receptors could partially explain differences in resistance. We next focused on up-regulated genes unique to either BALB/c or C57BL/6 derived macrophages and identified, using KEGG database, signal transduction pathways among the most relevant pathways unique to both susceptible and resistant derived macrophages. Indeed, genes unique to C57BL/6 BMdMs were associated with target of rapamycin (mTOR) signaling pathway while a range of genes unique to BALB/c BMdMs, belong to p53 signaling pathway. We next investigated whether, in a given mice strain derived macrophages, the different up-regulated unique genes could be coordinately regulated. Using GeneMapp Cytoscape, we showed that the induced genes unique to BALB/c or C57BL/6 BMdMs are interconnected. Finally, we examined whether the induced pathways unique to BALB/c derived macrophages interfere with the ones unique to C57BL/6 derived macrophages. Protein-protein interaction analysis using String database highlights the existence of a cross-talk between p53 and mTOR signaling pathways respectively specific to susceptible and resistant BMdMs. CONCLUSIONS: Taken together our results suggest that strains specific pathogenesis may be due to a difference in the magnitude of the same pathways and/or to differentially expressed pathways in the two mouse strains derived macrophages. We identify signal transduction pathways among the most relevant pathways modulated by L. major infection, unique to BALB/c and C57BL/6 BMdM and postulate that the interplay between these potentially interconnected pathways could direct the macrophage response toward a given phenotype.


Assuntos
Leishmania major/fisiologia , Macrófagos/metabolismo , Animais , Células da Medula Óssea/citologia , Bases de Dados Genéticas , Macrófagos/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Análise de Sequência com Séries de Oligonucleotídeos , Mapas de Interação de Proteínas , Transdução de Sinais/genética , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
4.
Front Immunol ; 14: 1212320, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38187392

RESUMO

Maternal immunisation, a low cost and high efficacy intervention is recommended for its pathogen specific protection. Evidence suggests that maternal immunisation has another significant impact: reduction of preterm birth (PTB), the single greatest cause of childhood morbidity and mortality globally. Our overarching question is: how does maternal immunisation modify the immune system in pregnant women and/or their newborn to reduce adverse pregnancy outcomes and enhance the newborn infant's capacity to protect itself from infectious diseases during early childhood? To answer this question we are conducting a multi-site, prospective observational cohort study collecting maternal and infant biological samples at defined time points during pregnancy and post-partum from nulliparous women. We aim to enrol 400 women and determine the immune trajectory in pregnancy and the impact of maternal immunisation (including influenza, pertussis and/or COVID-19 vaccines) on this trajectory. The results are expected to identify areas that can be targeted for future intervention studies.


Assuntos
Imunização , Nascimento Prematuro , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Gravidez , Imunidade , Estudos Observacionais como Assunto , Estudos Prospectivos
5.
EClinicalMedicine ; 62: 102082, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37538539

RESUMO

Background: Accumulating evidence indicates that an early, robust type 1 interferon (IFN) response to SARS-CoV-2 is important in determining COVID-19 outcomes, with an inadequate IFN response associated with disease severity. Our objective was to examine the prophylactic potential of IFN administration to limit viral transmission. Methods: A cluster randomised open label clinical trial was undertaken to determine the effects of pegylated IFNß-1a administration on SARS-CoV-2 household transmission between December 3rd, 2020 and June 29th, 2021. Index cases were identified from databases of confirmed SARS-CoV-2 individuals in Santiago, Chile. Households were cluster randomised (stratified by household size and age of index cases) to receive 3 doses of 125 µg subcutaneous pegylated IFNß-1a (172 households, 607 participants), or standard care (169 households, 565 participants). The statistical team was blinded to treatment assignment until the analysis plan was finalised. Analyses were undertaken to determine effects of treatment on viral shedding and viral transmission. Safety analyses included incidence and severity of adverse events in all treatment eligible participants in the standard care arm, or in the treatment arm with at least one dose administered. Clinicaltrials.gov identifier: NCT04552379. Findings: 5154 index cases were assessed for eligibility, 1372 index cases invited to participate, and 341 index cases and their household contacts (n = 831) enrolled. 1172 participants in 341 households underwent randomisation, with 607 assigned to receive IFNß-1a and 565 to standard care. Based on intention to treat (ITT) and per protocol (PP) analyses for the primary endpoints, IFNß-1a treatment did not affect duration of viral shedding in index cases (absolute risk reduction = -0.2%, 95% CI = -8.46% to 8.06%) and transmission of SARS-CoV-2 to household contacts (absolute risk reduction = 3.87%, 95% CI = -3.6% to 11.3%). Treatment with IFNß-1a resulted in significantly more treatment-related adverse events, but no increase in overall adverse events or serious adverse events. Interpretation: Based upon the primary analyses, IFNß-1a treatment did not affect duration of viral shedding or the probability of SARS-CoV-2 transmission to uninfected contacts within a household. Funding: Biogen PTY Ltd. Supply of interferon as 'Plegridy (peginterferon beta-1a).' The study was substantially funded by BHP Holdings Pty Ltd.

6.
Endocrinol Diabetes Metab ; 6(2): e402, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36606510

RESUMO

INTRODUCTION: The management of obesity is difficult with many failures of lifestyle measures, hence the need to broaden the range of treatments prescribed. The aim of our work was to study the influence of pre and probiotics on weight loss psychological profile and metabolic parameters in obese patients. METHODS: It is a clinical trial involving 45 obese patients, recruited from the Obesity Unit of the National Institute of Nutrition between March and August 2022 divided into three groups: diet only (low-carbohydrate and reduced energy diet), prebiotics (30 g of carob/day) and probiotics (one tablet containing Bifidobacterium longum, Lactobacillus helveticus, Lactococcus lactis, Streptococcus thermophilus/day). The three groups were matched for age, sex and BMI. Patients were seen after 1 month from the intervention. Anthropometric measures, biological parameters, dietary survey and psychological scores were performed. RESULTS: The average age of our population was 48.73 ± 7.7 years, with a female predominance. All three groups showed a significant decrease in weight, BMI and waist circumference with p < .05. Only the prebiotic and probiotic group showed a significant decrease in fat mass (p = .001) and a significant increase in muscle strength with p = .008 and .004, but the differences were not significant between the three groups. Our results showed also a significant decrease in insulinemia and HOMA-IR in the prebiotic group compared to the diet-alone group (p = .03; p = .012) and the probiotic group showed a significant decrease in fasting blood glucose compared to the diet alone group (p = .02). A significant improvement in sleep quality was noted in the prebiotic group (p = .02), with a significant decrease in depression, anxiety and stress in all three groups. CONCLUSIONS: The prescription of prebiotics and probiotics with the lifestyle measures seems interesting for the management of obesity especially if it is sarcopenic, in addition to the improvement of metabolic parameters and obesity-related psychiatric disorders.


Assuntos
Prebióticos , Probióticos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dieta , Obesidade , Redução de Peso
7.
Rom J Intern Med ; 61(1): 53-62, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36476238

RESUMO

INTRODUCTION: A substantial proportion of obese subjects are metabolically healthy and free from metabolic complications. Many mechanisms that could explain the existence of the metabolically healthy obese phenotype have been suggested, involving in particular a healthy lifestyle and diet. The aim of this study was to study the anthropometric, nutritional and biological profile of two groups: obese with metabolic syndrome (MS+) and obese without metabolic syndrome (MS-). METHODS: It is a cross-sectional study, conducted between January 2022 and 15 March 2022. We recruited 90 obese MS+ and 82 obese MS - . Both groups were matched for age and sex. The glycemia, triglycerides (TG), total cholesterol (TC), HDL-C, LDL-C were measured as well as the body composition and anthropometric data. The diet was determined by the 24-hour recalls. Eating disorders, sleep disorders (PSS4 scale) and depression (HADS) were also searched. RESULTS: In MS+ group we noticed: higher BMI, waist circumference, more caloric diet, elevated consumption of saccharides. This group had more eating disorders such as night eating syndrome and bulimia and sleeping disorders (sleep onset and total insomnia). MS + group was more stressed and depressed. The MS - group had a Mediterranean diet and had more intake of: EPA, DHA, olive oil, green tea, oleaginous fruits, linseed, vegetables and whole grains. They also practiced more fasting. CONCLUSIONS: It is important to know the protective nutritional factors of the metabolic syndrome in order to be able to focus on them during education sessions and thus protect the obese from metabolic complications.


Assuntos
Síndrome Metabólica , Humanos , Estudos Transversais , Síndrome Metabólica/complicações , Obesidade/complicações , Obesidade/metabolismo , Fatores de Risco , Triglicerídeos , Índice de Massa Corporal
8.
J Clin Med ; 12(2)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36675526

RESUMO

BACKGROUND: Taste disorders (TDs) have been reported to be very common in patients suffering from coronavirus disease 2019 (COVID-19), which is caused by the SARS-CoV-2 virus. In most of the hitherto conducted studies, a gustatory assessment was performed on the basis of surveys or self-reports by patients. The aim of our study was to undertake an objective assessment of four basic taste qualities by conducting tasting sessions that allowed detection thresholds in COVID-19 Tunisian patients and to study their associations with inflammation. METHODS: This analytical cross-sectional study was conducted on 89 patients aged between 21 to 70 years who had been diagnosed with COVID-19. We used Burghart taste strips to assess taste perception of the four taste qualities, i.e., sour, bitter, sweet, and salty. Serum levels of interleukin-1ß (IL-1ß), interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), and C-reactive protein (CRP) were measured. RESULTS: Taste disorders were reported by 40.4% of the patients, while objective assessments revealed that 63.8% of participants were suffering from hypogeusia and/or ageusia. Sour taste was the most altered (70.8%) gustatory quality. Patients with severe COVID-19 had significantly lower sour and bitter taste scores when compared to patients with minor/moderate forms. There was no significant association between serum inflammatory markers and taste disorders. However, the relationship between bitter and sweet taste qualities and IL-1ß levels was significant (p = 0.018 and p = 0.041). CONCLUSIONS: Our results demonstrate the interest in the objective assessment of taste dysfunctions in COVID-19 patients.

9.
Vaccine ; 40(11): 1534-1539, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-33863572

RESUMO

The BCG vaccine has long been recognized for reducing the risk to suffer from infectious diseases unrelated to its target disease, tuberculosis. Evidence from human trials demonstrate substantial reductions in all-cause mortality, especially in the first week of life. Observational studies have identified an association between BCG vaccination and reduced risk of respiratory infectious disease and clinical malaria later in childhood. The mechanistic basis for these pathogen-agnostic benefits, also known as beneficial non-specific effects (NSE) of BCG have been attributed to trained immunity, or epigenetic reprogramming of hematopoietic cells that give rise to innate immune cells responding more efficiently to a broad range of pathogens. Furthermore, within trained immunity, the focus so far has been on enhanced monocyte function. However, polymorphonuclear cells, namely neutrophils, are not only major constituents of the hematopoietic compartment but functionally as well as numerically represent a prominent component of the immune system. The beneficial NSEs of the BCG vaccine on newborn sepsis was recently demonstrated to be driven by a BCG-mediated numeric increase of neutrophils (emergency granulopoiesis (EG)). And experimental evidence in animal models suggest that BCG can modulate neutrophil function as well. Together, these findings suggest that neutrophils are crucial to at least the immediate beneficial NSE of the BCG vaccine. Efforts to uncover the full gamut of mechanisms underpinning the broad beneficial effects of BCG should therefore include neutrophils at the forefront.


Assuntos
Vacina BCG , Neutrófilos , Vacina BCG/imunologia , Humanos , Monócitos , Neutrófilos/imunologia , Tuberculose/imunologia , Tuberculose/prevenção & controle , Vacinação
10.
Front Immunol ; 13: 1043375, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36426360

RESUMO

A single birth-dose of Hepatitis B vaccine (HepB) can protect newborns from acquiring Hepatitis B infection through vertical transmission, though several follow-up doses are required to induce long-lived protection. In addition to stimulating antibodies, a birth-dose of HepB might also induce polyfunctional CD4+ T-cells, which may contribute to initial protection. We investigated whether vaccination with HepB in the first week of life induced detectable antigen-specific CD4+ T-cells after only a single dose and following completion of the entire HepB vaccine schedule (3 doses). Using HBsAg- stimulated peripheral blood mononuclear cells from 344 infants, we detected increased populations of antigen-specific polyfunctional CD154+IL-2+TNFα+ CD4+ T-cells following a single birth-dose of HepB in a proportion of infants. Frequencies of polyfunctional T-cells increased following the completion of the HepB schedule but increases in the proportion of responders as compared to following only one dose was marginal. Polyfunctional T-cells correlated positively with serum antibody titres following the birth dose (day30) and completion of the 3-dose primary HepB vaccine series (day 128). These data indicate that a single birth dose of HepB provides immune priming for both antigen-specific B- and T cells.


Assuntos
Vacinas contra Hepatite B , Leucócitos Mononucleares , Lactente , Recém-Nascido , Humanos , Linfócitos T Auxiliares-Indutores , Linfócitos T CD4-Positivos
11.
Pathogens ; 11(11)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36365042

RESUMO

In Australia, there is a paucity of data about the extent and impact of zoonotic tick-related illnesses. Even less is understood about a multifaceted illness referred to as Debilitating Symptom Complexes Attributed to Ticks (DSCATT). Here, we describe a research plan for investigating the aetiology, pathophysiology, and clinical outcomes of human tick-associated disease in Australia. Our approach focuses on the transmission of potential pathogens and the immunological responses of the patient after a tick bite. The protocol is strengthened by prospective data collection, the recruitment of two external matched control groups, and sophisticated integrative data analysis which, collectively, will allow the robust demonstration of associations between a tick bite and the development of clinical and pathological abnormalities. Various laboratory analyses are performed including metagenomics to investigate the potential transmission of bacteria, protozoa and/or viruses during tick bite. In addition, multi-omics technology is applied to investigate links between host immune responses and potential infectious and non-infectious disease causations. Psychometric profiling is also used to investigate whether psychological attributes influence symptom development. This research will fill important knowledge gaps about tick-borne diseases. Ultimately, we hope the results will promote improved diagnostic outcomes, and inform the safe management and treatment of patients bitten by ticks in Australia.

12.
Front Immunol ; 12: 690470, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34777332

RESUMO

Vaccination to prevent infectious disease is one of the most successful public health interventions ever developed. And yet, variability in individual vaccine effectiveness suggests that a better mechanistic understanding of vaccine-induced immune responses could improve vaccine design and efficacy. We have previously shown that protective antibody levels could be elicited in a subset of recipients with only a single dose of the hepatitis B virus (HBV) vaccine and that a wide range of antibody levels were elicited after three doses. The immune mechanisms responsible for this vaccine response variability is unclear. Using single cell RNA sequencing of sorted innate immune cell subsets, we identified two distinct myeloid dendritic cell subsets (NDRG1-expressing mDC2 and CDKN1C-expressing mDC4), the ratio of which at baseline (pre-vaccination) correlated with the immune response to a single dose of HBV vaccine. Our results suggest that the participants in our vaccine study were in one of two different dendritic cell dispositional states at baseline - an NDRG2-mDC2 state in which the vaccine elicited an antibody response after a single immunization or a CDKN1C-mDC4 state in which the vaccine required two or three doses for induction of antibody responses. To explore this correlation further, genes expressed in these mDC subsets were used for feature selection prior to the construction of predictive models using supervised canonical correlation machine learning. The resulting models showed an improved correlation with serum antibody titers in response to full vaccination. Taken together, these results suggest that the propensity of circulating dendritic cells toward either activation or suppression, their "dispositional endotype" at pre-vaccination baseline, could dictate response to vaccination.


Assuntos
Células Dendríticas/imunologia , Anticorpos Anti-Hepatite B/imunologia , Vacinas contra Hepatite B/imunologia , Hepatite B/prevenção & controle , Aprendizado de Máquina , Análise de Célula Única , Adulto , Idoso , Análise de Correlação Canônica , Células Dendríticas/metabolismo , Feminino , Perfilação da Expressão Gênica , Hepatite B/epidemiologia , Sequenciamento de Nucleotídeos em Larga Escala , Interações Hospedeiro-Patógeno , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Célula Única/métodos , Vacinação , Eficácia de Vacinas
13.
J Clin Transl Sci ; 5(1): e52, 2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-33948273

RESUMO

The Expanded Program for Immunization Consortium - Human Immunology Project Consortium study aims to employ systems biology to identify and characterize vaccine-induced biomarkers that predict immunogenicity in newborns. Key to this effort is the establishment of the Data Management Core (DMC) to provide reliable data and bioinformatic infrastructure for centralized curation, storage, and analysis of multiple de-identified "omic" datasets. The DMC established a cloud-based architecture using Amazon Web Services to track, store, and share data according to National Institutes of Health standards. The DMC tracks biological samples during collection, shipping, and processing while capturing sample metadata and associated clinical data. Multi-omic datasets are stored in access-controlled Amazon Simple Storage Service (S3) for data security and file version control. All data undergo quality control processes at the generating site followed by DMC validation for quality assurance. The DMC maintains a controlled computing environment for data analysis and integration. Upon publication, the DMC deposits finalized datasets to public repositories. The DMC architecture provides resources and scientific expertise to accelerate translational discovery. Robust operations allow rapid sharing of results across the project team. Maintenance of data quality standards and public data deposition will further benefit the scientific community.

15.
Front Immunol ; 11: 578505, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33329546

RESUMO

Neonates have heightened susceptibility to infections. The biological mechanisms are incompletely understood but thought to be related to age-specific adaptations in immunity due to resource constraints during immune system development and growth. We present here an extended analysis of our proteomics study of peripheral blood-plasma from a study of healthy full-term newborns delivered vaginally, collected at the day of birth and on day of life (DOL) 1, 3, or 7, to cover the first week of life. The plasma proteome was characterized by LC-MS using our established 96-well plate format plasma proteomics platform. We found increasing acute phase proteins and a reduction of respective inhibitors on DOL1. Focusing on the complement system, we found increased plasma concentrations of all major components of the classical complement pathway and the membrane attack complex (MAC) from birth onward, except C7 which seems to have near adult levels at birth. In contrast, components of the lectin and alternative complement pathways mainly decreased. A comparison to whole blood messenger RNA (mRNA) levels enabled characterization of mRNA and protein levels in parallel, and for 23 of the 30 monitored complement proteins, the whole blood transcript information by itself was not reflective of the plasma protein levels or dynamics during the first week of life. Analysis of immunoglobulin (Ig) mRNA and protein levels revealed that IgM levels and synthesis increased, while the plasma concentrations of maternally transferred IgG1-4 decreased in accordance with their in vivo half-lives. The neonatal plasma ratio of IgG1 to IgG2-4 was increased compared to adult values, demonstrating a highly efficient IgG1 transplacental transfer process. Partial compensation for maternal IgG degradation was achieved by endogenous synthesis of the IgG1 subtype which increased with DOL. The findings were validated in a geographically distinct cohort, demonstrating a consistent developmental trajectory of the newborn's immune system over the first week of human life across continents. Our findings indicate that the classical complement pathway is central for newborn immunity and our approach to characterize the plasma proteome in parallel with the transcriptome will provide crucial insight in immune ontogeny and inform new approaches to prevent and treat diseases.


Assuntos
Proteínas de Fase Aguda/metabolismo , Desenvolvimento Infantil , Proteínas do Sistema Complemento/metabolismo , Sistema Imunitário/metabolismo , Imunidade Inata , Imunoglobulinas/sangue , Proteoma , Fatores Etários , Proteínas do Sistema Complemento/genética , Humanos , Sistema Imunitário/crescimento & desenvolvimento , Sistema Imunitário/imunologia , Recém-Nascido , Estudo de Prova de Conceito , Mapas de Interação de Proteínas , Proteômica , RNA Mensageiro/sangue
16.
Front Immunol ; 11: 578801, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33329547

RESUMO

Background: Vaccination remains one of the most effective means of reducing the burden of infectious diseases globally. Improving our understanding of the molecular basis for effective vaccine response is of paramount importance if we are to ensure the success of future vaccine development efforts. Methods: We applied cutting edge multi-omics approaches to extensively characterize temporal molecular responses following vaccination with hepatitis B virus (HBV) vaccine. Data were integrated across cellular, epigenomic, transcriptomic, proteomic, and fecal microbiome profiles, and correlated to final HBV antibody titres. Results: Using both an unsupervised molecular-interaction network integration method (NetworkAnalyst) and a data-driven integration approach (DIABLO), we uncovered baseline molecular patterns and pathways associated with more effective vaccine responses to HBV. Biological associations were unravelled, with signalling pathways such as JAK-STAT and interleukin signalling, Toll-like receptor cascades, interferon signalling, and Th17 cell differentiation emerging as important pre-vaccination modulators of response. Conclusion: This study provides further evidence that baseline cellular and molecular characteristics of an individual's immune system influence vaccine responses, and highlights the utility of integrating information across many parallel molecular datasets.


Assuntos
Genômica , Vacinas contra Hepatite B/uso terapêutico , Hepatite B/prevenção & controle , Imunogenicidade da Vacina , Biologia de Sistemas , Vacinação , Adulto , Idoso , Epigênese Genética , Epigenômica , Fezes/microbiologia , Feminino , Microbioma Gastrointestinal , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Hepatite B/genética , Hepatite B/metabolismo , Hepatite B/microbiologia , Anticorpos Anti-Hepatite B/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Mapas de Interação de Proteínas , Proteômica , Fatores de Tempo , Transcriptoma , Resultado do Tratamento
17.
Front Pediatr ; 8: 197, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32426309

RESUMO

Background: Infection contributes to significant morbidity and mortality particularly in the very young and in low- and middle-income countries. While vaccines are a highly cost-effective tool against infectious disease little is known regarding the cellular and molecular pathways by which vaccines induce protection at an early age. Immunity is distinct in early life and greater precision is required in our understanding of mechanisms of early life protection to inform development of new pediatric vaccines. Methods and Analysis: We will apply transcriptomic, proteomic, metabolomic, multiplex cytokine/chemokine, adenosine deaminase, and flow cytometry immune cell phenotyping to delineate early cellular and molecular signatures that correspond to vaccine immunogenicity. This approach will be applied to a neonatal cohort in The Gambia (N ~ 720) receiving at birth: (1) Hepatitis B (HepB) vaccine alone, (2) Bacille Calmette Guerin (BCG) vaccine alone, or (3) HepB and BCG vaccines, (4) HepB and BCG vaccines delayed till day 10 at the latest. Each study participant will have a baseline peripheral blood sample drawn at DOL0 and a second blood sample at DOL1,-3, or-7 as well as late timepoints to assess HepB vaccine immunogenicity. Blood will be fractionated via a "small sample big data" standard operating procedure that enables multiple downstream systems biology assays. We will apply both univariate and multivariate frameworks and multi-OMIC data integration to identify features associated with anti-Hepatitis B (anti-HB) titer, an established correlate of protection. Cord blood sample collection from a subset of participants will enable human in vitro modeling to test mechanistic hypotheses identified in silico regarding vaccine action. Maternal anti-HB titer and the infant microbiome will also be correlated with our findings which will be validated in a smaller cohort in Papua New Guinea (N ~ 80). Ethics and Dissemination: The study has been approved by The Gambia Government/MRCG Joint Ethics Committee and The Boston Children's Hospital Institutional Review Board. Ethics review is ongoing with the Papua New Guinea Medical Research Advisory Committee. All de-identified data will be uploaded to public repositories following submission of study output for publication. Feedback meetings will be organized to disseminate output to the study communities. Clinical Trial Registration: Clinicaltrials.gov Registration Number: NCT03246230.

18.
Sci Transl Med ; 12(542)2020 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-32376769

RESUMO

Death from sepsis in the neonatal period remains a serious threat for millions. Within 3 days of administration, bacille Calmette-Guérin (BCG) vaccination can reduce mortality from neonatal sepsis in human newborns, but the underlying mechanism for this rapid protection is unknown. We found that BCG was also protective in a mouse model of neonatal polymicrobial sepsis, where it induced granulocyte colony-stimulating factor (G-CSF) within hours of administration. This was necessary and sufficient to drive emergency granulopoiesis (EG), resulting in a marked increase in neutrophils. This increase in neutrophils was directly and quantitatively responsible for protection from sepsis. Rapid induction of EG after BCG administration also occurred in three independent cohorts of human neonates.


Assuntos
Sepse Neonatal , Sepse , Fator Estimulador de Colônias de Granulócitos , Hematopoese , Humanos , Recém-Nascido , Sepse/prevenção & controle , Vacinação
19.
Front Immunol ; 11: 580373, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33250895

RESUMO

Conventional vaccine design has been based on trial-and-error approaches, which have been generally successful. However, there have been some major failures in vaccine development and we still do not have highly effective licensed vaccines for tuberculosis, HIV, respiratory syncytial virus, and other major infections of global significance. Approaches at rational vaccine design have been limited by our understanding of the immune response to vaccination at the molecular level. Tools now exist to undertake in-depth analysis using systems biology approaches, but to be fully realized, studies are required in humans with intensive blood and tissue sampling. Methods that support this intensive sampling need to be developed and validated as feasible. To this end, we describe here a detailed approach that was applied in a study of 15 healthy adults, who were immunized with hepatitis B vaccine. Sampling included ~350 mL of blood, 12 microbiome samples, and lymph node fine needle aspirates obtained over a ~7-month period, enabling comprehensive analysis of the immune response at the molecular level, including single cell and tissue sample analysis. Samples were collected for analysis of immune phenotyping, whole blood and single cell gene expression, proteomics, lipidomics, epigenetics, whole blood response to key immune stimuli, cytokine responses, in vitro T cell responses, antibody repertoire analysis and the microbiome. Data integration was undertaken using different approaches-NetworkAnalyst and DIABLO. Our results demonstrate that such intensive sampling studies are feasible in healthy adults, and data integration tools exist to analyze the vast amount of data generated from a multi-omics systems biology approach. This will provide the basis for a better understanding of vaccine-induced immunity and accelerate future rational vaccine design.


Assuntos
Vacinas contra Hepatite B/imunologia , Vírus da Hepatite B/fisiologia , Hepatite B/diagnóstico , Monitorização Imunológica/métodos , Vacinação/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Hepatite B/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Biologia de Sistemas , Resultado do Tratamento
20.
Mol Immunol ; 45(11): 3222-9, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18406464

RESUMO

The complex interactions between Leishmania and macrophages are central to the outcome of parasite infection. Disrupting signaling molecules to impair macrophage function, is a subversive strategy used by several pathogens. In the present study, we show that the initial contact of Leishmania with human naïves macrophages and murine Raw264.7 macrophage cell line induced a rapid and transient activation of extracellular-signal-regulated kinases 1 and 2 (ERK1/2) and p38MAPK. This activation is an actin-dependent mechanism that requires internalization of live parasites. Once stably infected, macrophages become unresponsive to subsequent parasite infection. Priming of cells with IFNgamma, prior to Leishmania infection, did not prevent the silencing of MAPKs pathways induced by Leishmania parasites. NF-kappaB transcriptional activity in response to Leishmania infection is also impaired in stably infected cells. This impairment was not due to MAPK deactivation as inhibition of ERK1/2 and p38MAPK, actually enhances the transcriptional activity of NF-kappaB in response to initial contact of Leishmania with the murine macrophagic cell line Raw264.7. Moreover, Leishmania parasites could not reverse the hyporesponsive state induced by LPS. These effects do not reflect a general down-regulation of macrophages signaling by parasites, as cells with established Leishmania infection display normal response to PMA. In addition we show that the mechanisms of Leishmania-induced hyporesponsive state is not due to the induction of a cellular tyrosine phosphatase activity as previously reported in LPS treated cells.


Assuntos
Regulação para Baixo , Espaço Intracelular/enzimologia , Leishmania/imunologia , Sistema de Sinalização das MAP Quinases , Macrófagos/enzimologia , Macrófagos/parasitologia , NF-kappa B/metabolismo , Animais , Linhagem Celular , Regulação para Baixo/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Humanos , Interferon gama/farmacologia , Espaço Intracelular/efeitos dos fármacos , Leishmania/efeitos dos fármacos , Leishmaniose/enzimologia , Leishmaniose/parasitologia , Lipopolissacarídeos/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Monócitos/efeitos dos fármacos , Monócitos/enzimologia , Monócitos/parasitologia , Parasitos/efeitos dos fármacos , Parasitos/imunologia , Fosforilação/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos
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