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1.
Biosensors (Basel) ; 14(10)2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39451698

RESUMO

Microbial fuel cells (MFCs) represent a promising technology for sustainable energy generation, which leverages the metabolic activities of microorganisms to convert organic substrates into electrical energy. In oil spill scenarios, hydrocarbonoclastic biofilms naturally form at the water-oil interface, creating a distinct environment for microbial activity. In this work, we engineered a novel MFC that harnesses these biofilms by strategically positioning the positive electrode at this critical junction, integrating the biofilm's natural properties into the MFC design. These biofilms, composed of specialized hydrocarbon-degrading bacteria, are vital in supporting electron transfer, significantly enhancing the system's power generation. Next-generation sequencing and scanning electron microscopy were used to characterize the microbial community, revealing a significant enrichment of hydrocarbonoclastic Gammaproteobacteria within the biofilm. Notably, key genera such as Paenalcaligenes, Providencia, and Pseudomonas were identified as dominant members, each contributing to the degradation of complex hydrocarbons and supporting the electrogenic activity of the MFCs. An electrochemical analysis demonstrated that the MFC achieved a stable power output of 51.5 µW under static conditions, with an internal resistance of about 1.05 kΩ. The system showed remarkable long-term stability, which maintained consistent performance over a 5-day testing period, with an average daily energy storage of approximately 216 mJ. Additionally, the MFC effectively recovered after deep discharge cycles, sustaining power output for up to 7.5 h before requiring a recovery period. Overall, the study indicates that MFCs based on hydrocarbonoclastic biofilms provide a dual-functionality system, combining renewable energy generation with environmental remediation, particularly in wastewater treatment. Despite lower power output compared to other hydrocarbon-degrading MFCs, the results highlight the potential of this technology for autonomous sensor networks and other low-power applications, which required sustainable energy sources. Moreover, the hydrocarbonoclastic biofilm-based MFC presented here offer significant potential as a biosensor for real-time monitoring of hydrocarbons and other contaminants in water. The biofilm's electrogenic properties enable the detection of organic compound degradation, positioning this system as ideal for environmental biosensing applications.


Assuntos
Fontes de Energia Bioelétrica , Biofilmes , Hidrocarbonetos , Energia Renovável , Águas Residuárias , Águas Residuárias/microbiologia , Hidrocarbonetos/metabolismo , Eletrodos , Biodegradação Ambiental
2.
Euro Surveill ; 29(16)2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38639092

RESUMO

Since late 2023, the Metropolitan City of Milan and surrounding areas (northern Italy) have been experiencing a resurgence of measles, with most cases detected starting from January 2024. During this brief period, we observed measles in travellers from endemic areas, participants in international events, vaccinees and healthcare workers. Indigenous cases have also been identified. Even though we have not yet identified large and disruptive outbreaks, strengthening surveillance and vaccination activities is pivotal to help limit the impact of measles spread.


Assuntos
Vírus do Sarampo , Sarampo , Humanos , Vírus do Sarampo/genética , Sarampo/epidemiologia , Sarampo/prevenção & controle , Surtos de Doenças , Vacinação , Itália/epidemiologia , Vacina contra Sarampo
3.
Bioelectrochemistry ; 158: 108711, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38626620

RESUMO

Addressing the simultaneous removal of multiple coexisting groundwater contaminants poses a significant challenge, primarily because of their different physicochemical properties. Indeed, different chemical compounds may necessitate establishing distinct, and sometimes conflicting, (bio)degradation and/or removal pathways. In this work, we investigated the concomitant anaerobic treatment of toluene and copper in a single-chamber bioelectrochemical cell with a potential difference of 1 V applied between the anode and the cathode. As a result, the electric current generated by the bioelectrocatalytic oxidation of toluene at the anode caused the abiotic reduction and precipitation of copper at the cathode, until the complete removal of both contaminants was achieved. Open circuit potential (OCP) experiments confirmed that the removal of copper and toluene was primarily associated with polarization. Analogously, abiotic experiments, at an applied potential of 1 V, confirmed that neither toluene was oxidized nor copper was reduced in the absence of microbial activity. At the end of each experiment, both electrodes were characterized by means of a comprehensive suite of chemical and microbiological analyses, evidencing a highly selected microbial community competent in the biodegradation of toluene in the anodic biofilm, and a uniform electrodeposition of spherical Cu2O nanoparticles over the cathode surface.


Assuntos
Cobre , Eletrodos , Água Subterrânea , Tolueno , Poluentes Químicos da Água , Tolueno/química , Tolueno/metabolismo , Cobre/química , Água Subterrânea/química , Água Subterrânea/microbiologia , Poluentes Químicos da Água/metabolismo , Anaerobiose , Biodegradação Ambiental , Técnicas Eletroquímicas/métodos , Oxirredução , Biofilmes , Purificação da Água/métodos , Fontes de Energia Bioelétrica/microbiologia
5.
Biomed Pharmacother ; 168: 115682, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37832410

RESUMO

Natural products are a rich source of bioactive molecules that have potential pharmacotherapeutic applications. In this study, we focused on Artemisia annua (A. annua) and its enriched extracts which were biologically evaluated in vitro as virucidal, antiviral, and antioxidant agents, with a potential application against the COVID-19 infection. The crude extract showed virucidal, antiviral and antioxidant effects in concentrations that did not affect cell viability. Scopoletin, arteannuin B and artemisinic acid (single fractions isolated from A. annua) exerted a considerable virucidal and antiviral effect in vitro starting from a concentration of 50 µg/mL. Data from Surface Plasmon Resonance (SPR) showed that the inhibition of the viral infection was due to the interaction of these compounds with the 3CLpro and Spike proteins of SARS-CoV-2, suggesting that the main interaction of compounds may interfere with the viral pathways during the insertion and the replication process. The present study suggests that natural extract of A. annua and its components could have a key role as antioxidants and antiviral agents and support the fight against SARS-CoV-2 variants and other possible emerging Coronaviruses.


Assuntos
Artemisia annua , COVID-19 , SARS-CoV-2 , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Artemisia annua/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/metabolismo , Antivirais/farmacologia , Antivirais/metabolismo
6.
ACS Infect Dis ; 9(7): 1310-1318, 2023 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-37358826

RESUMO

The current SARS-CoV-2 pandemic and the likelihood that new coronavirus strains will emerge in the immediate future point out the urgent need to identify new pan-coronavirus inhibitors. Strigolactones (SLs) are a class of plant hormones with multifaceted activities whose roles in plant-related fields have been extensively explored. Recently, we proved that SLs also exert antiviral activity toward herpesviruses, such as human cytomegalovirus (HCMV). Here we show that the synthetic SLs TH-EGO and EDOT-EGO impair ß-coronavirus replication including SARS-CoV-2 and the common cold human coronavirus HCoV-OC43. Interestingly, in silico simulations suggest the binding of SLs in the SARS-CoV-2 main protease (Mpro) active site, and this was further confirmed by an in vitro activity assay. Overall, our results highlight the potential efficacy of SLs as broad-spectrum antivirals against ß-coronaviruses, which may provide the rationale for repurposing this class of hormones for the treatment of COVID-19 patients.


Assuntos
COVID-19 , Humanos , Antivirais/farmacologia , Antivirais/química , SARS-CoV-2 , Peptídeo Hidrolases
7.
Biomed Pharmacother ; 158: 114083, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36495668

RESUMO

COronaVIrus Disease 2019 (COVID-19) is a newly emerging infectious disease that spread across the world, caused by the novel coronavirus Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS-CoV-2). Despite the advancements in science that led to the creation of the vaccine, there is still an urgent need for new antiviral drugs effective against SARS-CoV-2. This study aimed to investigate the antiviral effect of Paulownia tomentosa Steud extract against SARS-CoV-2 and to evaluate its antioxidant properties, including respiratory smooth muscle relaxant effects. Our results showed that P. tomentosa extract can inhibit viral replication by directly interacting with both the 3-chymotrypsin-like protease and spike protein. In addition, the phyto complex does not reduce lung epithelial cell viability and exerts a protective action in those cells damaged by tert-butyl hydroperoxide , a toxic agent able to alter cells' functions via increased oxidative stress. These data suggest the potential role of P. tomentosa extract in COVID-19 treatment, since this extract is able to act both as an antiviral and a cytoprotective agent in vitro.


Assuntos
COVID-19 , Humanos , Antivirais/uso terapêutico , SARS-CoV-2 , Antioxidantes/farmacologia , Tratamento Farmacológico da COVID-19 , Extratos Vegetais/farmacologia , Músculo Liso
8.
Data Brief ; 43: 108447, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35864873

RESUMO

Biofilm at water-oil interface of hypoxic water columns of microcosms, prepared from a lacustrine sample, that used diesel as a carbon source was found to show electrogenic properties. These microcosms named, Liquid Microbial Fuel Cells (L-MFCs) were electrically characterized using a custom electronic analyzer; accurate determination of voltage (V), power density (W/m 2), and current density (A/m2) for both charge and discharge phases was carried out. The instrument made it possible to carry out cell characterizations using resistive loads between 0 Ω (Ohm) and 10 kΩ. During the hypoxic and electrogenic phase, the synthesis of a system of "bacterial piping induction", produced filaments of hundreds of micrometers in which the microbial cells are hosted. Ultrastructural microscopy collected by scanning (SEM), transmission (TEM), immunofluorescence, Thunder Imager 3D, confocal laser scanning (CLSM) microscopy revealed a "myelin like" structure during filamentation processes; this "myelin like" structure exhibited cross-reactivity towards different epitopes of the myelin basic protein (MBP) and Claudin 11 (O4) of human oligodendrocytes. The disclosure of these filamentation processes could be helpful to describe further unconventional microbial structures in aquatic ecosystems and of the animal world. The data that support the findings of this study are openly available in at https://data.mendeley.com/datasets/7d35tj3j96/1.

9.
Viruses ; 14(6)2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35746712

RESUMO

Hantaviruses include several zoonotic pathogens that cause different syndromes in humans, with mortality rates ranging from 12 to 40%. Most commonly, humans get infected through the inhalation of aerosols or dust particles contaminated with virus-containing rodent excreta. Hantaviruses are specifically associated with the host species, and human cases depend on the presence and the dynamics of reservoir hosts. In this letter, we report the identification of Dobrava-Belgrade virus (DOBV) in the yellow-necked mouse (Apodemus flavicollis) from Italy. The virus was detected in the mountainous area of the province of Udine, bordering Austria and Slovenia, during an event of enhanced mortality in wild mice and voles. Despite serological evidence in rodents and humans that suggested the circulation of hantaviruses in Italy since 2000, this is the first virological confirmation of the infection. Phylogenetic analyses across the whole genome of the two detected viruses confirmed the host-specificity of DOBV sub-species and showed the highest identity with viruses identified in Slovenia and Croatia from both A. flavicollis and humans, with no signs of reassortment. These findings highlight the need for ecologists, veterinarians and medical doctors to come together in a coordinated approach in full compliance with the One Health concept.


Assuntos
Infecções por Hantavirus , Orthohantavírus , Animais , Áustria , Itália/epidemiologia , Camundongos , Murinae , Filogenia
10.
Viruses ; 14(4)2022 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-35458463

RESUMO

Subacute sclerosing panencephalitis (SSPE) is a late complication of measles virus infection that occurs in previously healthy children. This disease has no specific cure and is associated with a high degree of disability and mortality. In recent years, there has been an increase in its incidence in relation to a reduction in vaccination adherence, accentuated by the COVID-19 pandemic. In this article, we take stock of the current evidence on SSPE and report our personal clinical experience. We emphasise that, to date, the only effective protection strategy against this disease is vaccination against the measles virus.


Assuntos
COVID-19 , Sarampo , Panencefalite Esclerosante Subaguda , COVID-19/prevenção & controle , Criança , Humanos , Sarampo/epidemiologia , Sarampo/prevenção & controle , Vírus do Sarampo , Pandemias , Panencefalite Esclerosante Subaguda/epidemiologia , Panencefalite Esclerosante Subaguda/etiologia , Panencefalite Esclerosante Subaguda/prevenção & controle , Vacinação/efeitos adversos
12.
Environ Sci Pollut Res Int ; 28(20): 26187-26196, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33871774

RESUMO

Microbiomes of freshwater basins intended for human use remain poorly studied, with very little known about the microbial response to in situ oil spills. Lake Pertusillo is an artificial freshwater reservoir in Basilicata, Italy, and serves as the primary source of drinking water for more than one and a half million people in the region. Notably, it is located in close proximity to one of the largest oil extraction plants in Europe. The lake suffered a major oil spill in 2017, where approximately 400 tons of crude oil spilled into the lake; importantly, the pollution event provided a rare opportunity to study how the lacustrine microbiome responds to petroleum hydrocarbon contamination. Water samples were collected from Lake Pertusillo 10 months prior to and 3 months after the accident. The presence of hydrocarbons was verified and the taxonomic and functional aspects of the lake microbiome were assessed. The analysis revealed specialized successional patterns of lake microbial communities that were potentially capable of degrading complex, recalcitrant hydrocarbons, including aromatic, chloroaromatic, nitroaromatic, and sulfur containing aromatic hydrocarbons. Our findings indicated that changes in the freshwater microbial community were associated with the oil pollution event, where microbial patterns identified in the lacustrine microbiome 3 months after the oil spill were representative of its hydrocarbonoclastic potential and may serve as effective proxies for lacustrine oil pollution.


Assuntos
Poluição por Petróleo , Petróleo , Biodegradação Ambiental , Ecossistema , Europa (Continente) , Humanos , Hidrocarbonetos/análise , Itália
13.
Water Res ; 197: 117092, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33831774

RESUMO

The oil-water interface formed during an oil spill represents a challenging environment for pelagic communities living in aquatic ecosystems. At this anoxic barrier, we report the formation of a microbial hydrocarbonoclastic biofilm capable of electron transfer along the water column. This biofilm generated a membrane of surface-active compounds that allowed the spontaneous separation of electrical charges, causing the establishment of an anodic and a cathodic region and, as a result, the spontaneous creation of a liquid microbial fuel cell. Such floating biofilm was connected to the water column underneath by floating filaments that could contribute to oxygen reduction at distance. The filaments revealed an unusual lipid content induced by anoxic conditions, with prominent ultrastructural features similar to myelin found in oligodendrocytes of the vertebrate nervous system. Furthermore, these filaments showed an interesting cross-reactivity towards different epitopes of the myelin basic protein (MBP) and Claudin 11 (O4) of human oligodendrocytes. The presence of a network of filaments similar to myelin suggests the probable existence of evolutionary connections between very distant organisms. Collectively these results suggest a possible mechanism for how lake microbial communities can adapt to oil spills while offering an interesting starting point for technological developments of liquid microbial fuel cells related to the study of hydrocarbon-water interfaces. The data that support the findings of this study are openly available in figshare at https://figshare.com/s/72bc73ae14011dc7920d.


Assuntos
Poluição por Petróleo , Biofilmes , Ecossistema , Humanos , Hidrocarbonetos , Poluição por Petróleo/análise , Água
14.
Vector Borne Zoonotic Dis ; 17(7): 514-516, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28581349

RESUMO

Previous molecular-based studies have identified microorganisms of zoonotic and human nature in surface waters. Contaminated water can lead to human health issues, and the detection of pathogenic microorganisms is a valuable tool for the prevention of their spread. Water samples were taken from the River Tiber in and out of the city of Rome. Genetic analysis of the sequences obtained showed the presence of Coxiella burnetii in both the analyzed sites. Blast analysis showed that two sequences were identical to each other. Sequences from the polluted site showed high homology with different strains of C. burnetii. In this article, we report for the first time the presence of C. burnetii in environmental waters.


Assuntos
Coxiella burnetii/isolamento & purificação , Rios/microbiologia , Microbiologia da Água , Coxiella burnetii/genética , DNA Bacteriano/genética , Cidade de Roma
15.
Food Environ Virol ; 8(3): 206-14, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27117764

RESUMO

The transmission of water-borne pathogens typically occurs by a faecal-oral route, through inhalation of aerosols, or by direct or indirect contact with contaminated water. Previous molecular-based studies have identified viral particles of zoonotic and human nature in surface waters. Contaminated water can lead to human health issues, and the development of rapid methods for the detection of pathogenic microorganisms is a valuable tool for the prevention of their spread. The aims of this work were to determine the presence and identity of representative human pathogenic enteric viruses in water samples from six European countries by quantitative polymerase chain reaction (q-PCR) and to develop two quantitative PCR methods for Adenovirus 41 and Mammalian Orthoreoviruses. A 2-year survey showed that Norovirus, Mammalian Orthoreovirus and Adenoviruses were the most frequently identified enteric viruses in the sampled surface waters. Although it was not possible to establish viability and infectivity of the viruses considered, the detectable presence of pathogenic viruses may represent a potential risk for human health. The methodology developed may aid in rapid detection of these pathogens for monitoring quality of surface waters.


Assuntos
Enterovirus/isolamento & purificação , Lagos/virologia , Rios/virologia , Enterovirus/classificação , Enterovirus/genética , Europa (Continente) , Humanos , Reação em Cadeia da Polimerase
16.
Int J Environ Res Public Health ; 12(7): 7430-43, 2015 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-26133133

RESUMO

The coast of the Bulgarian Black Sea is a popular summer holiday destination. The Dam of Iskar is the largest artificial dam in Bulgaria, with a capacity of 675 million m3. It is the main source of tap water for the capital Sofia and for irrigating the surrounding valley. There is a close relationship between the quality of aquatic ecosystems and human health as many infections are waterborne. Rapid molecular methods for the analysis of highly pathogenic bacteria have been developed for monitoring quality. Mycobacterial species can be isolated from waste, surface, recreational, ground and tap waters and human pathogenicity of nontuberculose mycobacteria (NTM) is well recognized. The objective of our study was to perform molecular analysis for key-pathogens, with a focus on mycobacteria, in water samples collected from the Black Sea and the Dam of Iskar. In a two year period, 38 water samples were collected-24 from the Dam of Iskar and 14 from the Black Sea coastal zone. Fifty liter water samples were concentrated by ultrafiltration. Molecular analysis for 15 pathogens, including all species of genus Mycobacterium was performed. Our results showed presence of Vibrio spp. in the Black Sea. Rotavirus A was also identified in four samples from the Dam of Iskar. Toxigenic Escherichia coli was present in both locations, based on markers for stx1 and stx2 genes. No detectable amounts of Cryptosporidium were detected in either location using immunomagnetic separation and fluorescence microscopy. Furthermore, mass spectrometry analyses did not detect key cyanobacterial toxins. On the basis of the results obtained we can conclude that for the period 2012-2014 no Mycobacterium species were present in the water samples. During the study period no cases of waterborne infections were reported.


Assuntos
Medicina Ambiental , Mycobacterium/isolamento & purificação , Microbiologia da Água , Mar Negro , Bulgária , Cryptosporidium/isolamento & purificação , Ecossistema , Água Doce , Humanos , Recreação , Estações do Ano , Poluição da Água
17.
Arch Virol ; 160(4): 1065-73, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25666197

RESUMO

Marmota monax and its natural infection by woodchuck hepatitis virus (WHV) could be used as a predictive model for evaluating mechanisms of viral persistence during chronic hepatitis B virus (HBV) infection. The aim of this study was to investigate the presence of viral variants in the core gene of chronically WHV-infected woodchucks that showed two different patterns of peripheral blood mononuclear cells' (PBMCs') responses after stimulation with a specific WHV core peptide. Sequences' analysis of the WHV core region from eight WHV chronically infected woodchucks have been performed after in vitro stimulation with an immunodominant epitope of the WHV core protein (amino acids [aa] 96-110). Following this stimulation, positive PBMC responses at each point of follow-up were observed for four animals (group A), and weak immune responses at one or a few points of follow-up were observed for the remaining four animals (group B). The WHV core gene sequences contained amino acid deletions (aa 84-126, aa 84-113) in three of four group A animals and in none of group B animals. In the group A animals, the same deletions were observed in liver specimens and in two of four tumor specimens. Hepatocellular carcinoma (HCC) was diagnosed in all group A animals and in one group B animal. In conclusion, internal deletions in the core region correlated with a sustained PBMC response to the immunogenic peptide (96-110) of the core protein. A possible role of this relationship in hepatocarcinogenesis could be hypothesized; however, this needs to be investigated in patients with chronic HBV infection. The evaluation of virus-specific T-cell responses and T-cell epitopes that are possibly related to the mechanisms of viral evasion should be further investigated in order to design combined antiviral and immune approaches to control chronic HBV infection.


Assuntos
Proliferação de Células , Vírus da Hepatite B da Marmota/genética , Vírus da Hepatite B da Marmota/imunologia , Hepatite B Crônica/imunologia , Epitopos Imunodominantes/imunologia , Leucócitos Mononucleares/imunologia , Marmota , Proteínas do Core Viral/genética , Animais , Modelos Animais de Doenças , Feminino , Deleção de Genes , Vírus da Hepatite B da Marmota/fisiologia , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/fisiopatologia , Hepatite B Crônica/virologia , Humanos , Evasão da Resposta Imune , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/virologia , Masculino , Marmota/virologia , Proteínas do Core Viral/metabolismo
18.
J Med Virol ; 83(1): 178-86, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21108357

RESUMO

The Eastern woodchuck (Marmota monax) is a useful experimental model for evaluating antiviral therapy against chronic HBV infection. In the present study, an immunogenic complex (IGC) composed of immune sera containing PreS/S heterologous antibodies (anti-HBs) and serum-derived WHV particles containing 10(7) WHV-DNA copies/50 µl was developed. The IGC was administered to WHV-negative woodchucks and natural chronic WHV carriers, with the final aim of evaluating the outcome of WHV infection in both groups. A control group of three animals, infected experimentally with viral particles only, was also evaluated. Following IGC administration, two WHV-negative woodchucks exhibited persistent infection, with WHV-DNA levels 3-6 logs lower than the WHV-DNA levels of the controls that developed persistent infection. WHeAg seroconversion to anti-WHe was observed in these two woodchucks and in two control woodchucks which developed self-limited infection. In two of the four chronic carriers, the WHV-DNA level decreased significantly (by 4-6 logs) following IGC administration, with no rebound in viral load during follow-up. WHeAg seroconversion to anti-WHe was observed also in these animals. Analyses of the sequences derived from envelope proteins confirmed that IGC did not induce the emergence of resistant viral variants. The results of this study indicate that the IGC could be useful for breaking the tolerance in hepadnaviral infection and for boosting the host's innate and adoptive immune response.


Assuntos
Complexo Antígeno-Anticorpo/imunologia , Anticorpos Anti-Hepatite B/imunologia , Vírus da Hepatite B da Marmota/imunologia , Hepatite B/imunologia , Hepatite B/veterinária , Vírion/imunologia , Animais , Complexo Antígeno-Anticorpo/administração & dosagem , Sangue/virologia , DNA Viral/química , DNA Viral/genética , Modelos Animais de Doenças , Hepatite B/patologia , Hepatite B/virologia , Vírus da Hepatite B da Marmota/patogenicidade , Marmota , Dados de Sequência Molecular , Análise de Sequência de DNA , Resultado do Tratamento , Carga Viral
19.
Expert Opin Drug Discov ; 5(12): 1153-62, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22822718

RESUMO

Studies focused on the understanding of the molecular mechanisms involved in recovery or progression to chronicity of HBV may take advantage of natural and experimental models that mimic its properties. This is also of relevance for associated diseases such as cirrhosis and hepatocellulocarcinoma. The eastern woodchuck (Marmota monax) infected by the hepadnavirus woodchuck Hepatitis B virus (WHV) has been applied as a predictive model to support development of new HBV vaccines, antivirals, immunotherapies and combination therapies. This report summarizes studies carried out by our and other groups, with the application of this model in natural and experimental infections. Using standardized viral inocula in neonate and adult animals and newly established assays, the presence of the specific patterns of markers of acute, chronic and resolved infections and their relationships in the different virus-host interactions have been shown. B and T cell responses and T(H)1 cytokine expression have been shown to play a crucial role in the outcome of infection. The availability of the WHV/Marmota monax model and specific standardized assays may allow evaluation of new formulations of multimodal therapeutic strategies based on antiviral chemotherapy and immunomodulation. These may also include specifically targeted immunocomplexes. Such therapies could constitute new frontiers for the treatment of HBV chronic disease.

20.
Vaccine ; 27(25-26): 3271-5, 2009 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-19200835

RESUMO

Present efforts of HBV vaccine research are aimed at defining targeted antigen compositions and adjuvancy systems for earlier and broader immune responses and optimization of immunotherapeutic approaches. We have demonstrated the applicability of the WHV/Marmota monax model for the evaluation of immunogenicity and protection of new formulations of HBV vaccines for human use. Protective activity was evaluated following the administrations of HBV CHO-PreS/S and adjuvanted S/Core vaccines. The administration of a complex constituted by HBV derived woodchuck PreS/S antibodies coupled with WHV particles was able to induce inhibition of viral replication. Future studies on treatment of HBV chronic infection should be addressed to the evaluation of therapies combined with antivirals, vaccines and immunomodulatory compounds.


Assuntos
Vacinas contra Hepatite B/imunologia , Imunização , Animais , DNA Viral/sangue , Anticorpos Anti-Hepatite B/sangue , Lamivudina/farmacologia , Marmota , Vacinas Sintéticas/imunologia , Carga Viral
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