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1.
Sci Rep ; 14(1): 9917, 2024 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-38730038

RESUMO

Human immunodeficiency virus type 1 (HIV-1) remains a serious health threat in Indonesia. In particular, the CRF01_AE viruses were the predominant HIV-1 strains in various cities in Indonesia. However, information on the dynamic transmission characteristics and spatial-temporal transmission of HIV-1 CRF01_AE in Indonesia is limited. Therefore, the present study examined the spatial-temporal transmission networks and evolutionary characteristics of HIV-1 CRF01_AE in Indonesia. To clarify the epidemiological connection between CRF01_AE outbreaks in Indonesia and the rest of the world, we performed phylogenetic studies on nearly full genomes of CRF01_AE viruses isolated in Indonesia. Our results showed that five epidemic clades, namely, IDN clades 1-5, of CRF01_AE were found in Indonesia. To determine the potential source and mode of transmission of CRF01_AE, we performed Bayesian analysis and built maximum clade credibility trees for each clade. Our study revealed that CRF01_AE viruses were commonly introduced into Indonesia from Southeast Asia, particularly Thailand. The CRF01_AE viruses might have spread through major pandemics in Asian countries, such as China, Vietnam, and Laos, rather than being introduced directly from Africa in the early 1980s. This study has major implications for public health practice and policy development in Indonesia. The contributions of this study include understanding the dynamics of HIV-1 transmission that is important for the implementation of HIV disease control and prevention strategies in Indonesia.


Assuntos
Infecções por HIV , HIV-1 , Filogenia , Análise Espaço-Temporal , Indonésia/epidemiologia , HIV-1/genética , HIV-1/classificação , Humanos , Infecções por HIV/transmissão , Infecções por HIV/virologia , Infecções por HIV/epidemiologia , Teorema de Bayes , Genoma Viral
2.
Cells ; 13(8)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38667313

RESUMO

The cellular transmembrane protein MARCH8 impedes the incorporation of various viral envelope glycoproteins, such as the HIV-1 envelope glycoprotein (Env) and vesicular stomatitis virus G-glycoprotein (VSV-G), into virions by downregulating them from the surface of virus-producing cells. This downregulation significantly reduces the efficiency of virus infection. In this study, we aimed to further characterize this host protein by investigating its species specificity and the domains responsible for its antiviral activity, as well as its ability to inhibit cell-to-cell HIV-1 infection. We found that the antiviral function of MARCH8 is well conserved in the rhesus macaque, mouse, and bovine versions. The RING-CH domains of these versions are functionally important for inhibiting HIV-1 Env and VSV-G-pseudovirus infection, whereas tyrosine motifs are crucial for the former only, consistent with findings in human MARCH8. Through analysis of chimeric proteins between MARCH8 and non-antiviral MARCH3, we determined that both the N-terminal and C-terminal cytoplasmic tails, as well as presumably the N-terminal transmembrane domain, of MARCH8 are critical for its antiviral activity. Notably, we found that MARCH8 is unable to block cell-to-cell HIV-1 infection, likely due to its insufficient downregulation of Env. These findings offer further insights into understanding the biology of this antiviral transmembrane protein.


Assuntos
HIV-1 , Proteínas de Membrana , Humanos , Animais , Proteínas de Membrana/metabolismo , Células HEK293 , Ubiquitina-Proteína Ligases/metabolismo , Camundongos , Bovinos , Macaca mulatta , Infecções por HIV/virologia , Infecções por HIV/metabolismo , Antivirais/farmacologia , Domínios Proteicos , Produtos do Gene env do Vírus da Imunodeficiência Humana/metabolismo
3.
Biol Pharm Bull ; 46(8): 1079-1087, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37532559

RESUMO

Chronic hepatitis C virus (HCV) infection can lead to liver cirrhosis and hepatocellular carcinoma. Although current medications using direct-acting antivirals (DAAs) are highly effective and well-tolerated for treating patients with chronic HCV, high prices and the existence of DAA-resistant variants hamper treatment. There is thus a need for easily accessible antivirals with different mechanisms of action. During the screening of Indonesian medicinal plants for anti-HCV activity, we found that a crude extract of Dryobalanops aromatica leaves possessed strong antiviral activity against HCV. Bioassay-guided purification identified an oligostilbene, vaticanol B, as an active compound responsible for the anti-HCV activity. Vaticanol B inhibited HCV infection in a dose-dependent manner with 50% effective and cytotoxic concentrations of 3.6 and 559.5 µg/mL, respectively (Selectivity Index: 155.4). A time-of-addition study revealed that the infectivity of HCV virions was largely lost upon vaticanol B pretreatment. Also, the addition of vaticanol B following viral entry slightly but significantly suppressed HCV replication and HCV protein expression in HCV-infected and a subgenomic HCV replicon cells. Thus, the results clearly demonstrated that vaticanol B acted mainly on the viral entry step, while acting weakly on the post-entry step as well. Furthermore, co-treatment of the HCV NS5A inhibitor daclatasvir with vaticanol B increased the anti-HCV effect. Collectively, the present study has identified a plant-derived oligostilbene, vaticanol B, as a novel anti-HCV compound.


Assuntos
Dipterocarpaceae , Hepatite C Crônica , Hepatite C , Humanos , Antivirais/farmacologia , Antivirais/uso terapêutico , Hepacivirus , Hepatite C Crônica/tratamento farmacológico , Hepatite C/tratamento farmacológico , Replicação Viral
4.
Virus Res ; 334: 199176, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37473963

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has necessitated the global development of countermeasures since its outbreak. However, current therapeutics and vaccines to stop the pandemic are insufficient and this is mainly because of the emergence of resistant variants, which requires the urgent development of new countermeasures, such as antiviral drugs. Replicons, self-replicating RNAs that do not produce virions, are a promising system for this purpose because they safely recreate viral replication, enabling antiviral screening in biosafety level (BSL)-2 facilities. We herein constructed three pCC2Fos-based RNA replicons lacking some open reading frames (ORF) of SARS-CoV-2: the Δorf2-8, Δorf2.4, and Δorf2 replicons, and validated their replication in Huh-7 cells. The functionalities of the Δorf2-8 and Δorf2.4 replicons for antiviral drug screening were also confirmed. We conducted puromycin selection following the construction of the Δorf2.4-puro replicon by inserting a puromycin-resistant gene into the Δorf2.4 replicon. We observed the more sustained replication of the Δorf2.4-puro replicon by puromycin pressure. The present results will contribute to the establishment of a safe and useful replicon system for analyzing SARS-CoV-2 replication mechanisms as well as the development of novel antiviral drugs in BSL-2 facilities.


Assuntos
Antivirais , COVID-19 , Humanos , Antivirais/farmacologia , SARS-CoV-2/genética , COVID-19/genética , Avaliação Pré-Clínica de Medicamentos , Contenção de Riscos Biológicos , Replicação Viral , Replicon , Puromicina/farmacologia
5.
Trans R Soc Trop Med Hyg ; 117(8): 591-597, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37024111

RESUMO

BACKGROUND: Biomarkers that are cost-effective and accurate for predicting severe coronavirus disease 2019 (COVID-19) are urgently needed. We would like to assess the role of various inflammatory biomarkers on admission as disease severity predictors and determine the optimal cut-off of the neutrophile-to-lymphocyte ratio (NLR) for predicting severe COVID-19. METHODS: We conducted a cross-sectional study in six hospitals in Bali and recruited real-time PCR-confirmed COVID-19 patients aged >18 y from June to August 2020. Data collection included each patient's demographic, clinical, disease severity and hematological data. Multivariate and receiver operating characteristic curve analyses were performed. RESULTS: A total of 95 Indonesian COVID-19 patients were included. The highest NLR among severe patients was 11.5±6.2, followed by the non-severe group at 3.3±2.8. The lowest NLR was found in the asymptomatic group (1.9±1.1). The CD4+ and CD8+ values were lowest in the critical and severe disease groups. The area under the curve of NLR was 0.959. Therefore, the optimal NLR cut-off value for predicting severe COVID-19 was ≥3.55, with sensitivity at 90.9% and a specificity of 16.7%. CONCLUSIONS: Lower CD4+ and CD8+ and higher NLR values on admission are reliable predictors of severe COVID-19 among Indonesian people. NLR cut-off ≥3.55 is the optimal value for predicting severe COVID-19.


Assuntos
COVID-19 , Humanos , COVID-19/diagnóstico , Indonésia/epidemiologia , SARS-CoV-2 , Estudos Transversais , Prognóstico , Biomarcadores , Curva ROC , Linfócitos T CD8-Positivos , Linfócitos T CD4-Positivos , Estudos Retrospectivos
6.
Microbiol Immunol ; 67(6): 281-292, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36929353

RESUMO

Hepatitis B virus (HBV) is a leading cause of chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. Current therapeutic drugs for chronic HBV infection use IFN and nucleos(t)ide analogs; however, their efficacy is limited. Thus, there is an urgent need to develop new antivirals for HBV therapy. In this study, we identified a plant-derived polyphenolic bioflavonoid, amentoflavone, as a new anti-HBV compound. Amentoflavone treatment dose-dependently inhibited HBV infection in HBV-susceptible cells with HepG2-hNTCP-C4 and primary human hepatocyte PXB-cells. A mode-of-action study showed that amentoflavone inhibits the viral entry step, but not the viral internalization and early replication processes. Attachment of HBV particles as well as HBV preS1 peptide to HepG2-hNTCP-C4 cells was inhibited by amentoflavone. The transporter assay revealed that amentoflavone partly inhibits uptake of sodium taurocholate cotransporting polypeptide (NTCP)-mediated bile acid. Furthermore, effect of various amentoflavone analogs on HBs and HBe production from HBV-infected HepG2-hNTCP-C4 cells was examined. Robustaflavone exhibited comparable anti-HBV activity to that of amentoflavone and an amentoflavone-7,4', 4‴-trimethyl ether derivative (sciadopitysin) with moderate anti-HBV activity. Cupressuflavone or the monomeric flavonoid apigenin did not exhibit the antiviral activity. Amentoflavone and its structurally related biflavonoids may provide a potential drug scaffold in the design of a new anti-HBV drug inhibitor targeting NTCP.


Assuntos
Biflavonoides , Hepatite B , Humanos , Vírus da Hepatite B , Biflavonoides/farmacologia , Biflavonoides/metabolismo , Biflavonoides/uso terapêutico , Hepatite B/tratamento farmacológico , Hepatócitos , Antivirais/uso terapêutico , Internalização do Vírus
7.
AIDS Res Hum Retroviruses ; 39(3): 124-129, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36656663

RESUMO

Human immunodeficiency virus type 1 (HIV-1) is characterized by a large degree of genetic variability because of high rates of recombination and mutation, sizable population sizes, and rapid replication. Therefore, this study investigated HIV-1 subtype distribution and the appearance of drug resistance mutations (DRMs) in viruses that are prevalent in Makassar, South Sulawesi, Indonesia. The HIV-1 pol, env, and gag genes were amplified from 63 infected individuals and sequenced for a subtyping analysis. CRF01_AE was identified as the predominant HIV-1 circulating recombinant form (CRF) in Makassar, South Sulawesi, Indonesia. Subtype B and recombinant viruses containing CRF01_AE, CRF02_AG, and/or subtype B gene fragments were also detected. Several major DRMs against non-nucleoside reverse transcriptase inhibitors were found among antiretroviral therapy (ART)-experienced subjects, whereas ART-naive subjects did not possess any transmitted drug resistance. The prevalence of DRMs was very high among ART-experienced subjects; therefore, further surveillance is required in this region.


Assuntos
Infecções por HIV , HIV-1 , Humanos , HIV-1/genética , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Indonésia/epidemiologia , Farmacorresistência Viral/genética , Mutação , Filogenia , Genótipo
8.
PLoS One ; 17(10): e0274829, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36264936

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is a global threat. To forestall the pandemic, developing safe and effective vaccines is necessary. Because of the rapid production and little effect on the host genome, mRNA vaccines are attractive, but they have a relatively low immune response after a single dose. Replicon RNA (repRNA) is a promising vaccine platform for safety and efficacy. RepRNA vaccine encodes not only antigen genes but also the genes necessary for RNA replication. Thus, repRNA is self-replicative and can play the role of an adjuvant by itself, which elicits robust immunity. This study constructed and evaluated a repRNA vaccine in which the gene encoding the spike (S) protein of SARS-CoV-2 was inserted into a replicon of yellow fever virus 17D strain. Upon electroporation of this repRNA into baby hamster kidney cells, the S protein and yellow fever virus protein were co-expressed. Additionally, the self-replication ability of repRNA vaccine was confirmed using qRT-PCR, demonstrating its potency as a vaccine. Immunization of C57BL/6 mice with 1 µg of the repRNA vaccine induced specific T-cell responses but not antibody responses. Notably, the T-cell response induced by the repRNA vaccine was significantly higher than that induced by the nonreplicative RNA vaccine in our experimental model. In the future, it is of the essence to optimize vaccine administration methods and improve S protein expression, like protection of repRNA by nanoparticles and evasion of innate immunity of the host to enhance the immune-inducing ability of the repRNA vaccine.


Assuntos
COVID-19 , SARS-CoV-2 , Camundongos , Animais , Humanos , SARS-CoV-2/genética , Vacinas contra COVID-19 , Vírus da Febre Amarela , COVID-19/prevenção & controle , Camundongos Endogâmicos C57BL , Vacinas Sintéticas/genética , Replicon , RNA/genética , Glicoproteína da Espícula de Coronavírus , Anticorpos Antivirais , Anticorpos Neutralizantes , Vacinas de mRNA
9.
Vaccines (Basel) ; 10(9)2022 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-36146489

RESUMO

Infection with viruses belonging to the genus Flavivirus, such as Japanese encephalitis virus (JEV) and dengue virus (DENV), is a worldwide health problem. Vaccines against JEV and DENV are currently available. However, the dengue vaccine possibly increases the risk of severe dengue due to antibody-dependent enhancement (ADE). Moreover, the Japanese encephalitis (JE) vaccine reportedly induces cross-reactive ADE-prone antibodies against DENV, potentially leading to symptomatic dengue. Therefore, it is necessary to eliminate the risk of ADE through vaccination. In this study, we attempted to develop a JE vaccine that does not induce ADE of DENV infection using an epitope modification strategy. We found that an ADE-prone monoclonal antibody cross-reactive to DENV and JEV recognizes the 106th amino acid residue of the E protein of JEV (E-106). The JE DNA vaccine with a mutation at E-106 (E-106 vaccine) induced comparable neutralizing antibody titers against JEV to those induced by the wild-type JE DNA vaccine. Meanwhile, the E-106 vaccine induced 64-fold less cross-reactive ADE-prone antibodies against DENV. The mutation did not compromise the protective efficacy of the vaccine in the lethal JEV challenge experiment. Altogether, the modification of a single amino acid residue identified in this study helped in the development of an ADE-free JE vaccine.

10.
Pathogens ; 11(5)2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35631064

RESUMO

The increase in antibiotic resistance in non-typhoidal Salmonella enterica (NTS) has been confirmed in Indonesia by this study. We confirmed the virulence genes and antimicrobial susceptibilities of clinical NTS (n = 50) isolated from chicken meat in Indonesia and also detected antimicrobial resistance genes. Of 50 strains, 30 (60%) were non-susceptible to nalidixic acid (NA) and all of them had amino acid mutations in gyrA. Among 27 tetracycline (TC) non-susceptible strains, 22 (81.5%) had tetA and/or tetB. The non-susceptibility rates to ampicillin, gentamicin or kanamycin were lower than that of NA or TC, but the prevalence of blaTEM or aadA was high. Non-susceptible strains showed a high prevalence of virulence genes compared with the susceptible strains (tcfA, p = 0.014; cdtB, p < 0.001; sfbA, p < 0.001; fimA, p = 0.002). S. Schwarzengrund was the most prevalent serotype (23 strains, 46%) and the most frequently detected as multi-antimicrobial resistant. The prevalence of virulence genes in S. Schwarzengrund was significantly higher than other serotypes in hlyE (p = 0.011) and phoP/Q (p = 0.011) in addition to the genes above. In conclusion, NTS strains isolated from Indonesian chicken had a high resistance to antibiotics and many virulence factors. In particular, S. Schwarzengrund strains were most frequently detected as multi-antimicrobial resistant and had a high prevalence of virulence genes.

11.
PLoS One ; 17(4): e0261802, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35389997

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), is transmitted mainly by droplet or aerosol infection; however, it may also be transmitted by contact infection. SARS-CoV-2 that adheres to environmental surfaces remains infectious for several days. We herein attempted to inactivate SARS-CoV-2 and influenza A virus adhering to an environmental surface by dry fogging hypochlorous acid solution and hydrogen peroxide solution. SARS-CoV-2 and influenza virus were air-dried on plastic plates and placed into a test chamber for inactivation by the dry fogging of these disinfectants. The results obtained showed that the dry fogging of hypochlorous acid solution and hydrogen peroxide solution inactivated SARS-CoV-2 and influenza A virus in CT value (the product of the disinfectant concentration and contact time)-dependent manners. SARS-CoV-2 was more resistant to the virucidal effects of aerosolized hypochlorous acid solution and hydrogen peroxide solution than influenza A virus; therefore, higher concentrations of disinfectants or longer contact times were required to inactivate SARS-CoV-2 than influenza A virus. The present results provide important information for the development of a strategy that inactivates SARS-CoV-2 and influenza A virus on environmental surfaces by spatial fogging.


Assuntos
COVID-19 , Desinfetantes , Vírus da Influenza A , Desinfetantes/farmacologia , Humanos , Peróxido de Hidrogênio/farmacologia , Ácido Hipocloroso/farmacologia , SARS-CoV-2 , Inativação de Vírus
12.
Microbiol Spectr ; 10(1): e0061821, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35019698

RESUMO

The host transmembrane protein MARCH8 is a RING finger E3 ubiquitin ligase that downregulates various host transmembrane proteins, such as MHC-II. We have recently reported that MARCH8 expression in virus-producing cells impairs viral infectivity by reducing virion incorporation of not only HIV-1 envelope glycoprotein but also vesicular stomatitis virus G-glycoprotein through two different pathways. However, the MARCH8 inhibition spectrum remains largely unknown. Here, we show the antiviral spectrum of MARCH8 using viruses pseudotyped with a variety of viral envelope glycoproteins. Infection experiments revealed that viral envelope glycoproteins derived from the rhabdovirus, arenavirus, coronavirus, and togavirus (alphavirus) families were sensitive to MARCH8-mediated inhibition. Lysine mutations at the cytoplasmic tails of rabies virus-G, lymphocytic choriomeningitis virus glycoproteins, SARS-CoV and SARS-CoV-2 spike proteins, and Chikungunya virus and Ross River virus E2 proteins conferred resistance to MARCH8. Immunofluorescence showed impaired downregulation of the mutants of these viral envelope glycoproteins by MARCH8, followed by lysosomal degradation, suggesting that MARCH8-mediated ubiquitination leads to intracellular degradation of these envelopes. Indeed, rabies virus-G and Chikungunya virus E2 proteins proved to be clearly ubiquitinated. We conclude that MARCH8 has inhibitory activity on a variety of viral envelope glycoproteins whose cytoplasmic lysine residues are targeted by this antiviral factor. IMPORTANCE A member of the MARCH E3 ubiquitin ligase family, MARCH8, downregulates many different kinds of host transmembrane proteins, resulting in the regulation of cellular homeostasis. On the other hands, MARCH8 acts as an antiviral factor when it binds to and downregulates HIV-1 envelope glycoprotein and vesicular stomatitis virus G-glycoprotein that are viral transmembrane proteins. This study reveals that, as in the case of cellular membrane proteins, MARCH8 shows broad-spectrum inhibition against various viral envelope glycoproteins by recognizing their cytoplasmic lysine residues, resulting in lysosomal degradation.


Assuntos
Antivirais/farmacologia , Lisina/efeitos dos fármacos , Ubiquitina-Proteína Ligases/farmacologia , Proteínas do Envelope Viral/química , Western Blotting , Regulação para Baixo , Células HEK293 , Células HeLa , Humanos , Imunoprecipitação , Lisina/metabolismo , Ubiquitinação/fisiologia , Proteínas do Envelope Viral/efeitos dos fármacos
13.
Sci Rep ; 11(1): 12987, 2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-34155267

RESUMO

Dengue virus (DENV), from the genus flavivirus of the family flaviviridae, causes serious health problems globally. Human monoclonal antibodies (HuMAb) can be used to elucidate the mechanisms of neutralization and antibody-dependent enhancement (ADE) of DENV infections, leading to the development of a vaccine or therapeutic antibodies. Here, we generated eight HuMAb clones from an Indonesian patient infected with DENV. These HuMAbs exhibited the typical characteristics of weak neutralizing antibodies including high cross-reactivity with other flaviviruses and targeting of the fusion loop epitope (FLE). However, one of the HuMAbs, 3G9, exhibited strong neutralization (NT50 < 0.1 µg/ml) and possessed a high somatic hyper-mutation rate of the variable region, indicating affinity-maturation. Administration of this antibody significantly prolonged the survival of interferon-α/ß/γ receptor knockout C57BL/6 mice after a lethal DENV challenge. Additionally, Fc-modified 3G9 that had lost their in vitro ADE activity showed enhanced therapeutic potency in vivo and competed strongly with an ADE-prone antibody in vitro. Taken together, the affinity-matured FLE-targeting antibody 3G9 exhibits promising features for therapeutic application including a low NT50 value, potential for treatment of various kinds of mosquito-borne flavivirus infection, and suppression of ADE. This study demonstrates the therapeutic potency of affinity-matured FLE-targeting antibodies.


Assuntos
Anticorpos Monoclonais/farmacologia , Afinidade de Anticorpos , Antígenos Virais , Antivirais/farmacologia , Vírus da Dengue/efeitos dos fármacos , Dengue/virologia , Epitopos , Animais , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Afinidade de Anticorpos/imunologia , Antígenos Virais/química , Antígenos Virais/imunologia , Antivirais/uso terapêutico , Dengue/tratamento farmacológico , Dengue/imunologia , Vírus da Dengue/imunologia , Mapeamento de Epitopos , Epitopos/química , Epitopos/imunologia , Humanos , Hibridomas , Camundongos , Modelos Moleculares , Testes de Neutralização , Conformação Proteica , Proteínas Recombinantes , Relação Estrutura-Atividade
14.
Virus Res ; 294: 198278, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33388392

RESUMO

The analysis of neutralizing epitope of dengue virus (DENV) is important for the development of an effective dengue vaccine. A potent neutralizing mouse monoclonal antibody named 7F4 was previously reported and, here, we further analyzed the detailed epitope of this antibody. 7F4 recognized a novel conformational epitope close to the N-67 glycan on the envelope protein. This antibody was specific to the DENV that lacks N-67 glycan, including the Mochizuki strain. Interestingly, the Mochizuki strain acquired N-67 glycan by 7F4 selective pressure. Considering that most of the currently circulating DENVs possess N-67 glycan, DENVs may have evolved to escape from antibodies targeting 7F4 epitope, suggesting the potency of this neutralizing epitope. In addition, this study demonstrated the existence of the epitopes close to 7F4 epitope and their crucial role in neutralization. In conclusion, the epitopes close to the N-67 glycan are attractive targets for the dengue vaccine antigen. Further analysis of this epitope is warranted.


Assuntos
Vacinas contra Dengue , Vírus da Dengue , Dengue , Animais , Anticorpos Monoclonais , Anticorpos Neutralizantes , Anticorpos Antivirais , Vírus da Dengue/genética , Epitopos , Camundongos , Polissacarídeos , Proteínas do Envelope Viral/genética
15.
Sci Rep ; 11(1): 2229, 2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33500537

RESUMO

The development of specific antiviral compounds to SARS-CoV-2 is an urgent task. One of the obstacles for the antiviral development is the requirement of biocontainment because infectious SARS-CoV-2 must be handled in a biosafety level-3 laboratory. Replicon, a non-infectious self-replicative viral RNA, could be a safe and effective tool for antiviral evaluation. Herein, we generated a PCR-based SARS-CoV-2 replicon. Eight fragments covering the entire SARS-CoV-2 genome except S, E, and M genes were amplified with HiBiT-tag sequence by PCR. The amplicons were ligated and in vitro transcribed to RNA. The cells electroporated with the replicon RNA showed more than 3000 times higher luminescence than MOCK control cells at 24 h post-electroporation, indicating robust translation and RNA replication of the replicon. The replication was drastically inhibited by remdesivir, an RNA polymerase inhibitor for SARS-CoV-2. The IC50 of remdesivir in this study was 0.29 µM, generally consistent to the IC50 obtained using infectious SARS-CoV-2 in a previous study (0.77 µM). Taken together, this system could be applied to the safe and effective antiviral evaluation without using infectious SARS-CoV-2. Because this is a PCR-based and transient replicon system, further improvement including the establishment of stable cell line must be achieved.


Assuntos
Antivirais/farmacologia , Desenho de Fármacos , SARS-CoV-2/efeitos dos fármacos , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/farmacologia , Alanina/análogos & derivados , Alanina/farmacologia , Animais , Células CHO , COVID-19 , Chlorocebus aethiops , Cricetulus , Avaliação Pré-Clínica de Medicamentos , Eletroporação , Genoma Viral , Células HEK293 , Humanos , Concentração Inibidora 50 , Cinética , Fases de Leitura Aberta , Reação em Cadeia da Polimerase , RNA Viral , RNA Polimerase Dependente de RNA , SARS-CoV-2/fisiologia , Regiões não Traduzidas , Células Vero , Vírion , Replicação Viral/efeitos dos fármacos
16.
Jpn J Infect Dis ; 74(1): 48-53, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-32741932

RESUMO

JC polyomavirus (JCPyV) causes progressive multifocal leukoencephalopathy (PML), a demyelinating disease of the central nervous system affecting immunocompromised patients. The study of PML-type JCPyV in vitro has been limited owing to the inefficient propagation of the virus in cultured cells. In this study, we carried out long-term culture of COS-7 cells (designated as COS-IMRb cells) transfected with PML-type M1-IMRb, an adapted viral DNA with a rearranged non-coding control region (NCCR). The JCPyV derived from COS-IMRb cells were characterized by analyzing the viral replication, amount of virus by hemagglutination (HA), production of viral protein 1 (VP1), and structure of the NCCR. HA assays indicated the presence of high amounts of PML-type JCPyV in COS-IMRb cells. Immunostaining showed only a small population of JCPyV carrying COS-IMRb cells to be VP1-positive. Sequencing analysis of the NCCR of JCPyV after long-term culture revealed that the NCCR of M1-IMRb was conserved in COS-IMRb cells without any point mutation. The JCPyV genomic DNA derived from a clone of COS-IMRb-3 cells was detected, via Southern blotting, as a single band of approximately 5.1 kbp without deletion. These findings suggest the potential of using COS-IMRb-3 cells as a useful tool for screening anti-JCPyV drugs.


Assuntos
Vírus JC/crescimento & desenvolvimento , Vírus JC/genética , Leucoencefalopatia Multifocal Progressiva/virologia , Cultura de Vírus/métodos , Animais , Southern Blotting/métodos , Células COS , Chlorocebus aethiops , Replicação do DNA , DNA Viral/isolamento & purificação , Hemaglutinação , Humanos , Transfecção , Proteínas Virais/genética , Proteínas Virais/metabolismo , Replicação Viral
17.
Acta Med Indones ; 52(4): 366-374, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33377882

RESUMO

BACKGROUND: human immunodeficiency virus type 1 (HIV-1) infection is a serious public health threat worldwide. Medan is one example of big cities in Indonesia with a high prevalence of HIV-1 infection; however, quite a limited study had conducted for detecting the circulation of HIV-1 subtypes in Medan. In addition, a serious factor that can implicate the treatment of HIV-1-infected individuals is the emergence of drug resistance mutations. Thus, the information on HIV-1 infection is important to improve the treatment for infected individuals. METHODS: sixty-seven antiretroviral therapy-experienced, HIV-1-infected individuals were recruited for this study. HIV-1 pol genes encoding protease (PR genes) and reverse transcriptase (RT gene), as well as env and gag genes, were amplified from DNA derived from peripheral blood samples. HIV-1 subtyping was conducted to study the dominant HIV-1 subtype circulating in the region. In addition, the emergence of drug resistance mutations was analyzed based on the guidelines published by the International Antiviral Society-United States of America (IAS-USA). RESULTS: the dominant HIV-1 subtype found in Medan was CRF01_AE (77.6%). In addition, another subtype and recombinant viruses such as recombinants between CRF01_AE and subtype B (12.2%), subtype B (4.1%), and CRF02_AG (4.1%) were also found. Drug resistance-associated major mutations were found in 21.6% (8/37) of RT genes and 3.1% (1/32) of PR genes studied. CONCLUSION: our study showed that the dominant subtype found in ART-experienced, HIV-1-infected individuals residing in Medan was CRF01_AE. The emergence of drug resistance mutations in RT and PR genes indicated the importance to monitor the prevalence of drug resistance mutations among HIV-1-infected individuals in Medan.


Assuntos
Farmacorresistência Viral , Genótipo , Infecções por HIV/virologia , HIV-1/genética , Mutação , Adulto , Terapia Antirretroviral de Alta Atividade , Feminino , Infecções por HIV/tratamento farmacológico , Transcriptase Reversa do HIV/genética , HIV-1/classificação , HIV-1/efeitos dos fármacos , Humanos , Indonésia , Masculino , Adulto Jovem
18.
Germs ; 10(4): 174-183, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33134195

RESUMO

INTRODUCTION: The present study investigated the HIV-1 subtype classification in addition to prevalence of drug resistance mutations (DRMs) in antiretroviral therapy (ART)-experienced and ART-naïve residents of Pontianak, West Kalimantan, Indonesia. METHODS: Whole blood samples collected from 30 HIV-1-infected individuals, comprising 19 ART-experienced and 11 ART-naïve individuals, were subjected to RNA and DNA extraction, followed by HIV-1 genes amplification and sequencing analysis. HIV-1 subtyping was classified on viral pol genes encoding reverse transcriptase (RT gene) and protease (PR gene) accompanied by the env and gag genes. DRMs in the RT and PR genes were also analyzed. RESULTS: CRF01_AE was identified as the predominant circulating recombinant form (CRF) of HIV-1 in both ART-experienced and ART-naïve individuals. In addition, CRF02_AG, subtype B, recombinant virus expressing CRF01_AE and subtype B viral genomic fragments, also recombinant virus containing CRF01_AE and CRF02_AG genomic fragments were also identified. Acquired drug resistance (ADR) was identified in 28.5% of ART-experienced individuals, while no transmitted drug resistance was identified in ART-naïve individuals. CONCLUSIONS: This study identified CRF01_AE as the most predominant HIV-1 CRF distributing in Pontianak, Indonesia. The prevalence of ADR is considered to be high; thus, further surveillance is needed in this region.

19.
Viruses ; 12(11)2020 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-33126728

RESUMO

HIV-1 cure strategy by means of proviral knock-out using CRISPR-Cas9 has been hampered by the emergence of viral resistance against the targeting guide RNA (gRNA). Here, we proposed multiple, concentrated gRNA attacks against HIV-1 regulatory genes to block viral escape. The T cell line were transduced with single and multiple gRNAs targeting HIV-1 tat and rev using lentiviral-based CRISPR-Cas9, followed by replicative HIV-1NL4-3 challenge in vitro. Viral p24 rebound was observed for almost all gRNAs, but multiplexing three tat-targeting gRNAs maintained p24 suppression and cell viability, indicating the inhibition of viral escape. Multiplexed tat gRNAs inhibited acute viral replication in the 2nd round of infection, abolished cell-associated transmission to unprotected T cells, and maintained protection through 45 days, post-infection (dpi) after a higher dose of HIV-1 infection. Finally, we describe here for the first time the assembly of all-in-one lentiviral vectors containing three and six gRNAs targeting tat and rev. A single-vector tat-targeting construct shows non-inferiority to the tat-targeting multi-vector in low-dose HIV-1 infection. We conclude that Cas9-induced, DNA repair-mediated mutations in tat are sufficiently deleterious and deplete HIV-1 fitness, and multiplexed disruption of tat further limits the possibility of an escape mutant arising, thus elevating the potential of CRISPR-Cas9 to achieve a long-term HIV-1 cure.


Assuntos
Sistemas CRISPR-Cas , HIV-1/imunologia , RNA Guia de Cinetoplastídeos/genética , Linfócitos T/virologia , Produtos do Gene tat do Vírus da Imunodeficiência Humana/genética , Linhagem Celular , Edição de Genes , Vetores Genéticos , Genoma Viral , HIV-1/fisiologia , Humanos , Lentivirus/genética , Mutação , Provírus/genética , Linfócitos T/imunologia , Replicação Viral/genética , Produtos do Gene tat do Vírus da Imunodeficiência Humana/antagonistas & inibidores
20.
Infect Dis Rep ; 12(Suppl 1): 8740, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32874468

RESUMO

The presence of transmitted drug resistance (TDR) in human immunodeficiency virus type 1 (HIV-1) infected individuals naive to antiretroviral therapy, may affect the effectiveness of treatment. Jakarta, the capital city of Indonesia, recorded the highest number of cumulative HIV infection cases in the country. This study aimed to identify on the appearance of TDR, as well as to identify HIV-1 subtypes circulating among treatment-naive individuals in Jakarta. Whole blood samples collected from 43 HIV-1 infected, treatment-naive individuals. Viral subtyping and drug resistance testing were performed on HIV-1 pol genes amplified using nested polymerase chain reaction. CRF01_AE was detected most frequently in Jakarta (73.08%). Drug resistance-related major mutation was not detected in protease fragments of pol gene, but two major mutations, K103N (6.67%) and Y181C (6.67%), were detected in reverse transcriptase fragments of pol gene. Our results suggest that TDR was emerged in Jakarta at a certain extent, thus further surveillance study to monitor the TDR prevalence and circulating HIV-1 subtypes in this region is considered to be necessary.

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