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1.
Microb Pathog ; 194: 106827, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39084308

RESUMEN

Integration of nucleic acid sequences of Reticuloendotheliosis virus (REV) in Avipoxvirus(APV) has become commonplace. In this study, 4 strains of suspected Fowlpox virus (FPV) and 1 strain of suspected Pigeonpox virus (PPV) collected in Taiyuan, Shanxi Province were cultured in chicken embryos, and the 4b core protein gene was amplified by PCR, and the identity and genome similarity were determined by sequence analysis. The sequences between the end of ORF201 and the beginning of ORF203 of FPV and PPV were then amplified, sequenced, and subjected to sequence comparison to determine genome similarity. The results showed that the isolates were 4 strains of FPV and 1 strain of PPV. The 4 isolated strains of FPV belong to type A1 virus, with 100 % identity to each other and to the FWPV-09-Jilin strain isolated in Jilin, China, and the lowest identity to the type B2 virus TNPV5/NZL/2009, which is only 74 %. PPV belongs to type A2 virus, and its identity with local strain of fowlpox virus was 90.1 %, with the highest identity of 100 % with PPLH and ROPI/W370/ON/2012 and ow_2017_3 strains, which also belong to type A2 pigeonpox virus, and the lowest identity of 73.7 % with TNPV5/NZL/2009, a type B2 virus. The complete genome of REV sequences integrated into FPV and PPV were amplified, and 5 REV nucleic acid sequences were obtained after sequencing and concatenation, with lengths ranging from 7942 to 8005 bp. The identity analysis results indicate that it has high identity with isolates from Northeast China, Guangdong, and Guangxi regions in China. Based on its gp90 protein gene, the REV integrated into the poxvirus belong to type III, with the highest identity of 99.9% with strains such as APC-566 and CY1111, and the lowest identity with REV-Anhui1, at 95.4 %. The length of the pol gene varies among different strains of REV, and its encoded amino acid changes significantly after position 675, with deletions and alterations. This study indicates that all fowlpox viruses isolated in Taiyuan, Shanxi Province have integrated the entire REV gene sequence, with high identity between them. At the same time, it indicates that the pigeonpox virus isolate has also integrated the entire REV gene sequence, and has the highest identity with the integrated REV gene sequence in fowlpox virus.


Asunto(s)
Avipoxvirus , Virus de la Viruela de las Aves de Corral , Genoma Viral , Filogenia , Virus de la Reticuloendoteliosis , Secuenciación Completa del Genoma , Animales , Genoma Viral/genética , Virus de la Reticuloendoteliosis/genética , Virus de la Reticuloendoteliosis/aislamiento & purificación , Avipoxvirus/genética , Avipoxvirus/clasificación , Avipoxvirus/aislamiento & purificación , Virus de la Viruela de las Aves de Corral/genética , Virus de la Viruela de las Aves de Corral/aislamiento & purificación , China , Embrión de Pollo , Integración Viral/genética , Pollos/virología , Sistemas de Lectura Abierta/genética , Enfermedades de las Aves de Corral/virología , Análisis de Secuencia de ADN , ADN Viral/genética , Viruela Aviar/virología , Infecciones por Poxviridae/virología , Infecciones por Poxviridae/veterinaria
2.
Eur J Pharm Sci ; 200: 106834, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38906232

RESUMEN

The hepatitis B virus (HBV) capsid or core protein is a promising drug target currently being investigated for potential curative therapies for chronic HBV infection. In this study, we performed extensive in vitro and in vivo characterization of a novel and potent HBV core protein assembly modulator (CpAM), CU15, for both anti-HBV activity and druggability properties. CU15 potently inhibited HBV DNA replication in in vitro HBV-infected HepG2.2.15 cells (EC50 of 8.6 nM), with a low serum shift. It was also effective in inhibiting HBV DNA and cccDNA formation in de novo HBV-infected primary human hepatocytes. Furthermore, CU15 was active across several HBV genotypes and across clinically relevant core protein variants. After oral administration to an in vivo HBV mouse model, CU15 significantly reduced plasma HBV DNA and RNA levels, at plasma exposure consistent with the estimated in vitro potency. In vitro, CU15 exhibited excellent passive permeability and relatively high metabolic stability in liver preparations across species (human > dog> rat). In vitro human liver microsomal studies suggest that the compound's major metabolic pathway is CYP3A-mediated oxidation. Consistent with the in vitro findings, CU15 is a compound with a low-to-moderate clearance and high oral bioavailability in rats and dogs. Based on the apparent in vitro-in vivo correlation observed, CU15 has the potential to exhibit low clearance and high oral bioavailability in humans. In addition, CU15 also showed low drug-drug interaction liability with an acceptable in vitro safety profile (IC50 > 10 µM).


Asunto(s)
Antivirales , Virus de la Hepatitis B , Hepatitis B Crónica , Humanos , Animales , Antivirales/farmacología , Antivirales/uso terapéutico , Antivirales/farmacocinética , Hepatitis B Crónica/tratamiento farmacológico , Virus de la Hepatitis B/efectos de los fármacos , Células Hep G2 , Perros , Masculino , Ratas , ADN Viral , Ratones , Hepatocitos/metabolismo , Hepatocitos/efectos de los fármacos , Microsomas Hepáticos/metabolismo , Replicación Viral/efectos de los fármacos , Proteínas del Núcleo Viral/metabolismo , Ratas Sprague-Dawley
3.
Virus Genes ; 60(5): 510-516, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38866926

RESUMEN

In order to study the integration of reticuloendotheliosis virus (REV) in pigeonpox virus (PPV), we collected suspected pigeonpox disease material, amplified the 4b core protein gene of PPV, the gp90 gene of REV, and the integrated sequence fragments from the end of the ORF201 segment of PPV to the beginning of the LTR of REV, and sequenced these genes. The results showed that a 4b core protein fragment of 332 bp was amplified and identified as pigeonpox virus, which was named SX/TY/LTR 01/2023. Sequence analysis showed that the pigeonpox virus isolate belonged to genotype A2, which was the closest to the domestic CVL strain, with a identity of 99.4%. A band of 1191 bp was amplified from the gp90 gene of REV, named SX/TY/PPV-REV01/2023, and sequence analysis indicated that REV belonged to genotype III. The sequence analysis showed that REV belonged to genotype III, and belonged to the same large branch as the domestic isolates JSRD0701 and LNR0801, with 99.3% identity. The integrated sequence fragment was amplified to a band of 637 bp, which determined that the REV sequence was integrated in the PPV rather than a mixed infection of the two viruses. This indicates that REV was integrated in this isolation of PPV, suggesting that pigeon farms need to prevent reticuloendotheliosis at the same time when preventing pigeonpox.


Asunto(s)
Avipoxvirus , Filogenia , Virus de la Reticuloendoteliosis , Animales , Virus de la Reticuloendoteliosis/genética , Virus de la Reticuloendoteliosis/aislamiento & purificación , Avipoxvirus/genética , Avipoxvirus/aislamiento & purificación , Avipoxvirus/clasificación , Columbidae/virología , Infecciones por Poxviridae/virología , Infecciones por Poxviridae/veterinaria , Genotipo , Análisis de Secuencia de ADN , Enfermedades de las Aves/virología
4.
Vaccine ; 42(22): 125992, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-38811268

RESUMEN

Self-assembling virus-like particles (VLPs) are promising platforms for vaccine development. However, the unpredictability of the physical properties, such as self-assembly capability, hydrophobicity, and overall stability in engineered protein particles fused with antigens, presents substantial challenges in their downstream processing. We envision that these challenges can be addressed by combining more precise computer-aided molecular dynamics (MD) simulations with experimental studies on the modified products, with more to-date forcefield descriptions and larger models closely resembling real assemblies, realized by rapid advancement in computing technology. In this study, three chimeric designs based on the hepatitis B core (HBc) protein as model vaccine candidates were constructed to study and compare the influence of inserted epitopes as well as insertion strategy on HBc modifications. Large partial VLP models containing 17 chains for the HBc chimeric model vaccines were constructed based on the wild-type (wt) HBc assembly template. The findings from our simulation analysis have demonstrated good consistency with experimental results, pertaining to the surface hydrophobicity and overall stability of the chimeric vaccine candidates. Furthermore, the different impact of foreign antigen insertions on the HBc scaffold was investigated through simulations. It was found that separately inserting two epitopes into the HBc platform at the N-terminal and the major immunogenic regions (MIR) yields better results compared to a serial insertion at MIR in terms of protein structural stability. This study substantiates that an MD-guided design approach can facilitate vaccine development and improve its manufacturing efficiency by predicting products with extreme surface hydrophobicity or structural instability.


Asunto(s)
Antígenos del Núcleo de la Hepatitis B , Simulación de Dinámica Molecular , Nanopartículas , Vacunas de Partículas Similares a Virus , Antígenos del Núcleo de la Hepatitis B/inmunología , Antígenos del Núcleo de la Hepatitis B/genética , Antígenos del Núcleo de la Hepatitis B/química , Vacunas de Partículas Similares a Virus/inmunología , Vacunas de Partículas Similares a Virus/química , Nanopartículas/química , Interacciones Hidrofóbicas e Hidrofílicas , Vacunas contra Hepatitis B/inmunología , Vacunas contra Hepatitis B/química , Epítopos/inmunología , Epítopos/química , Epítopos/genética , Humanos
5.
J Biomed Sci ; 31(1): 34, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38561844

RESUMEN

BACKGROUND: It is generally believed that hepatitis B virus (HBV) core protein (HBc) dephosphorylation (de-P) is important for viral DNA synthesis and virion secretion. HBV polymerase contains four domains for terminal protein, spacer, reverse transcriptase, and RNase H activities. METHODS: HBV Polymerase mutants were transfected into HuH-7 cells and assayed for replication and HBc de-P by the Phos-tag gel analysis. Infection assay was performed by using a HepG2-NTCP-AS2 cell line. RESULTS: Here, we show that a novel phosphatase activity responsible for HBc de-P can be mapped to the C-terminal domain of the polymerase overlapping with the RNase H domain. Surprisingly, while HBc de-P is crucial for viral infectivity, it is essential for neither viral DNA synthesis nor virion secretion. The potential origin, significance, and mechanism of this polymerase-associated phosphatase activity are discussed in the context of an electrostatic homeostasis model. The Phos-tag gel analysis revealed an intriguing pattern of "bipolar distribution" of phosphorylated HBc and a de-P HBc doublet. CONCLUSIONS: It remains unknown if such a polymerase-associated phosphatase activity can be found in other related biosystems. This polymerase-associated phosphatase activity could be a druggable target in clinical therapy for hepatitis B.


Asunto(s)
Cápside , Virus de la Hepatitis B , Virus de la Hepatitis B/genética , Cápside/metabolismo , Ensamble de Virus/genética , ADN Viral , ARN Viral/metabolismo , Proteínas de la Cápside/metabolismo , Replicación Viral/genética , Ribonucleasa H/metabolismo , Monoéster Fosfórico Hidrolasas/metabolismo
6.
Biology (Basel) ; 13(4)2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38666843

RESUMEN

Formoterol, a ß2-adrenergic receptor (ß2AR) agonist, shows promise in various diseases, but its effectiveness in Parkinson's disease (PD) is debated, with unclear regulation of mitochondrial homeostasis. This study employed a cell model featuring mitochondrial ubiquinol-cytochrome c reductase core protein 1 (UQCRC1) variants associated with familial parkinsonism, demonstrating mitochondrial dysfunction and dynamic imbalance, exploring the therapeutic effects and underlying mechanisms of formoterol. Results revealed that 24-h formoterol treatment enhanced cell proliferation, viability, and neuroprotection against oxidative stress. Mitochondrial function, encompassing DNA copy number, repatriation, and complex III-linked respiration, was comprehensively restored, along with the dynamic rebalance of fusion/fission events. Formoterol reduced extensive hypertubulation, in contrast to mitophagy, by significantly upregulating protein Drp-1, in contrast to fusion protein Mfn2, mitophagy-related protein Parkin. The upstream mechanism involved the restoration of ERK signaling and the inhibition of Akt overactivity, contingent on the activation of ß2-adrenergic receptors. Formoterol additionally aided in segregating healthy mitochondria for distribution and transport, therefore normalizing mitochondrial arrangement in mutant cells. This study provides preliminary evidence that formoterol offers neuroprotection, acting as a mitochondrial dynamic balance regulator, making it a promising therapeutic candidate for PD.

7.
J Virol Methods ; 326: 114907, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38432358

RESUMEN

Adenovirus protein VII (pVII) is a highly basic core protein, bearing resemblance to mammalian histones. Despite its diverse functions, a comprehensive understanding of its structural intricacies and the mechanisms underlying its functions remain elusive, primarily due to the complexity of producing a good amount of soluble pVII. This study aimed to optimise the expression and purification of recombinant pVII from four different adenoviruses with a simple vector construct. This study successfully determined the optimal conditions for efficiently purifying pVII across four adenovirus species, revealing the differential preference for bacterial expression systems. The One Shot BL21 Star (DE3) proved favourable over Rosetta 2 (DE3) pLysS with consistent levels of expression between IPTG-induced and auto-induction. We demonstrated that combining chemical and mechanical cell lysis is possible and highly effective. Other noteworthy benefits were observed in using RNase during sample processing. The addition of RNase has significantly improved the quality and quantity of the purified protein as confirmed by chromatographic and western blot analyses. These findings established a solid groundwork for pVII purification methodologies and carry the significant potential to assist in unveiling the core structure of pVII, its arrangement within the core, DNA condensation intricacies, and potential pathways for nuclear transport.


Asunto(s)
Infecciones por Adenoviridae , Proteínas del Núcleo Viral , Animales , Proteínas del Núcleo Viral/genética , Adenoviridae/genética , Proteínas Virales/genética , Proteínas Virales/metabolismo , Ribonucleasas/metabolismo , Mamíferos/metabolismo
8.
Clin Mol Hepatol ; 30(3): 375-387, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38528825

RESUMEN

BACKGROUND/AIMS: Oral EDP-514 is a potent core protein inhibitor of hepatitis B virus (HBV) replication, which produced a >4-log viral load reduction in HBV-infected chimeric mice with human liver cells. This study evaluated the safety, pharmacokinetics, and antiviral activity of three doses of EDP-514 in treatment-naive viremic patients with HBeAgpositive or -negative chronic HBV infection. METHODS: Patients with HBsAg detectable at screening and at least 6 months previously were eligible. HBeAg-positive and -negative patients had a serum/plasma HBV DNA level ≥20,000 and ≥2,000 IU/mL, respectively. Twenty-five patients were randomized to EDP-514 200 (n=6), 400 (n=6) or 800 mg (n=7) or placebo (n=6) once daily for 28 days. RESULTS: A dose-related increase in EDP-514 exposure (AUClast and Cmax) was observed across doses. At Day 28, mean reductions in HBV DNA were -2.9, -3.3, -3.5 and -0.2 log10 IU/mL with EDP-514 200 mg, 400 mg, 800 mg, and placebo groups, respectively. The corresponding mean change from baseline for HBV RNA levels was -2.9, -2.4, -2.0, and -0.02 log10 U/mL. No virologic failures were observed. No clinically meaningful changes from baseline were observed for HBsAg, HBeAg or HBcrAg. Nine patients reported treatment emergent adverse events of mild or moderate severity with no discontinuations, serious AEs or deaths. CONCLUSION: In treatment-naïve viremic patients, oral EDP-514 was generally safe and well-tolerated, displayed PK profile supportive of once-daily dosing, and markedly reduced HBV DNA and HBV RNA.


Asunto(s)
Antivirales , ADN Viral , Antígenos e de la Hepatitis B , Virus de la Hepatitis B , Hepatitis B Crónica , Humanos , Hepatitis B Crónica/tratamiento farmacológico , Antivirales/uso terapéutico , Antivirales/farmacocinética , Masculino , Adulto , Femenino , Virus de la Hepatitis B/genética , Persona de Mediana Edad , Antígenos e de la Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/sangre , Carga Viral , Método Doble Ciego , Viremia/tratamiento farmacológico , Adulto Joven , Relación Dosis-Respuesta a Droga , Guanina/análogos & derivados , Organofosfonatos
9.
J Virol Methods ; 323: 114852, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37979698

RESUMEN

Hepatitis C virus (HCV) is the major cause of chronic hepatitis and hepatocellular carcinoma. Among its structural proteins, the HCV core protein has been implicated in liver disease. Understanding the role of HCV core proteins in viral diseases is crucial to elucidating disease mechanisms and identifying potential drug targets. However, purification challenges hinder the comprehensive elucidation of the structure and biochemical properties of HCV core proteins. In this study, we successfully solubilized bacterially expressed core protein using a high-salt and detergent-containing buffer and bypassed the denaturing-refolding process. Size-exclusion chromatography revealed three distinct peaks in the HCV-infected cell lysate, with the bacterially expressed soluble core protein corresponding to its second peak. Using a combination of affinity, size exclusion, and multi-modal chromatography purification techniques, we achieved a purity of > 95% for the core protein. Analytical ultracentrifugation revealed monomer formation in the solution. Far UV Circular dichroism spectroscopy identified 25.53% alpha helices and 20.26% beta sheets. These findings strongly suggest that the purified core proteins retained one of the native structures observed in HCV-infected cells.


Asunto(s)
Carcinoma Hepatocelular , Hepatitis C , Neoplasias Hepáticas , Humanos , Hepacivirus , Proteínas del Núcleo Viral
10.
Viruses ; 15(12)2023 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-38140607

RESUMEN

Hepatitis B virus (HBV) is the primary contributor to severe liver ailments, encompassing conditions such as cirrhosis and hepatocellular carcinoma. Globally, 257 million people are affected by HBV annually and 887,000 deaths are attributed to it, representing a substantial health burden. Regrettably, none of the existing therapies for chronic hepatitis B (CHB) have achieved satisfactory clinical cure rates. This issue stems from the existence of covalently closed circular DNA (cccDNA), which is difficult to eliminate from the nucleus of infected hepatocytes. HBV genetic material is composed of partially double-stranded DNA that forms complexes with viral polymerase inside an icosahedral capsid composed of a dimeric core protein. The HBV core protein, consisting of 183 to 185 amino acids, plays integral roles in multiple essential functions within the HBV replication process. In this review, we describe the effects of sulfamoyl-based carboxamide capsid assembly modulators (CAMs) on capsid assembly, which can suppress HBV replication and disrupt the production of new cccDNA. We present research on classical, first-generation sulfamoyl benzocarboxamide CAMs, elucidating their structural composition and antiviral efficacy. Additionally, we explore newly identified sulfamoyl-based CAMs, including sulfamoyl bicyclic carboxamides, sulfamoyl aromatic heterocyclic carboxamides, sulfamoyl aliphatic heterocyclic carboxamides, cyclic sulfonamides, and non-carboxamide sulfomoyl-based CAMs. We believe that certain molecules derived from sulfamoyl groups have the potential to be developed into essential components of a well-suited combination therapy, ultimately yielding superior clinical efficacy outcomes in the future.


Asunto(s)
Hepatitis B Crónica , Hepatitis B , Humanos , Virus de la Hepatitis B/metabolismo , Antivirales/uso terapéutico , Nucleocápside/metabolismo , Hepatitis B Crónica/tratamiento farmacológico , Cápside/metabolismo , Proteínas de la Cápside/genética , ADN Circular/genética , ADN Circular/metabolismo , Replicación Viral , ADN Viral/genética , ADN Viral/metabolismo , Hepatitis B/tratamiento farmacológico , Hepatitis B/metabolismo
11.
J Biomol Struct Dyn ; : 1-14, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37908124

RESUMEN

Self-assembling protein nanoparticles showed promise for vaccine design due to efficient antigen presentations and safety. However, the unpredictable formations of epitopes-fused protein assemblies remain challenging in the upstream design. This study suggests employing molecular dynamic (MD) simulations to investigate the assembly properties of Hepatitis B core protein (HBc) from thermodynamic perspectives. Eight HBc derivatives were expressed in E. coli, with their self-assembly properties characterised by high-performance liquid chromatography and transmission electron microscopy. MD simulations on the dimers, based on AlphaFold-predicted 3D structures, analysed the derivative at the atomic level. Results revealed that HBc derivatives can form dissociative polymers or large multi-subunit structures due to assembly failures. The instability of the dimer in aqueous solvents or inappropriate intradimer distances could cause major assembly failures. Polar solvation energies played a vital role too in forming assemble-incompetent dimers. Importantly, our study demonstrated that MD simulations on dimers can provide preliminary predictions on the assembly properties of HBc derivatives, thus aiding vaccine design by lowering the risk of self-assembling failures in engineered proteins.Communicated by Ramaswamy H. Sarma.

12.
J Clin Exp Hepatol ; 13(6): 1008-1016, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37975051

RESUMEN

Background: Hepatocellular carcinoma (HCC) is the most common primary malignant tumor of the liver. Aim: This study aimed to assess serum human telomerase enzyme (hTERT) levels and their relation to the progression of liver disease. Also, it aimed to assess the effect of hepatitis C virus (HCV) core protein on memory T-cells in HCV patients with or without HCC and the correlation between memory cell phenotype and the progression of the disease in the same patients. Methods: HTERT level in serum was assessed through relative quantitative RT-PCR. Flow cytometric analysis was used to assess T-cell responsiveness (as IFN- γ secretion) before and after stimulation with HCV core protein and the memory CD8+ cell phenotype using several differentiation markers. Results: HTERT was found to be increased in a stepwise manner upon comparing its level in controls, chronic hepatitis patients, cirrhotic patients, and HCC patients. T-cells showed a similar manner of stepwise decrease in response (decreased IFN- γ secretion) in HCC patients compared to HCV patients without HCC and controls. Also, late differentiated memory cells (CD8+, CD27-, CD28-, CD45RA+, and CCR7-) were depleted in HCC patients compared to HCV patients without HCC. Conclusion: These results suggest a negative correlation between hTERT and IFN- γ secretion by T-cells in HCV patients and that this relationship, along with the depletion of late differentiated memory cells, could help the progression of liver disease to HCC.

13.
J Med Virol ; 95(10): e29195, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37881005

RESUMEN

Hepatitis B e antigen (HBeAg) loss represents a late stage of chronic hepatitis B virus (HBV) infection associated with a drastic decrease in HBV-DNA, a lower risk of disease progression, and the occurrence of several mutations in the preCore/core region. However, the underlying mechanisms supporting the downregulation of viral replication have yet to be elucidated. In the present study, the analysis of the frequency of subgenotype D1 core protein (HBc) mutations associated with HBeAg status revealed a higher mutation rate in HBeAg-negative sequences compared to HBeAg-positive ones. Particularly, 22 amino acids exhibited a higher frequency of mutation in HBeAg-negative sequences, while the remaining residues showed a high degree of conservation. Subsequently, the assessment of HBc mutants derived from HBeAg-negative patients in viral structure and replicative capacity revealed that HBc mutations have the ability to modulate the subcellular localization of the protein (either when the protein was expressed alone or in the context of viral replication), capsid assembly, and, depending on specific mutation patterns, alter covalently closed circular DNA (cccDNA) recycling and up- or downregulate viral replication. In conclusion, HBc mutations associated with HBeAg-negative status impact on various stages of the HBV life cycle modulating viral replication during the HBeAg-negative stage of infection.


Asunto(s)
Virus de la Hepatitis B , Hepatitis B Crónica , Humanos , Antígenos e de la Hepatitis B/genética , Antígenos e de la Hepatitis B/análisis , Mutación , Replicación Viral , ADN Viral/genética , ADN Viral/análisis
14.
J Virol ; 97(10): e0089223, 2023 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-37772835

RESUMEN

IMPORTANCE: The hepatitis C virus is associated with nearly 300,000 deaths annually. At the core of the virus is an RNA-protein complex called the nucleocapsid, which consists of the viral genome and many copies of the core protein. Because the assembly of the nucleocapsid is a critical step in viral replication, a considerable amount of effort has been devoted to identifying antiviral therapeutics that can bind to the core protein and disrupt assembly. Although several candidates have been identified, little is known about how they interact with the core protein or how those interactions alter the structure and thus the function of this viral protein. Our work biochemically characterizes several of these binding interactions, highlighting both similarities and differences as well as strengths and weaknesses. These insights bolster the notion that this viral protein is a viable target for novel therapeutics and will help to guide future developments of these candidate antivirals.


Asunto(s)
Antivirales , Hepacivirus , Proteínas del Núcleo Viral , Humanos , Antivirales/metabolismo , Antivirales/farmacología , Hepacivirus/química , Hepacivirus/efectos de los fármacos , Hepacivirus/metabolismo , Hepatitis C/tratamiento farmacológico , Hepatitis C/virología , Nucleocápside/antagonistas & inhibidores , Nucleocápside/química , Nucleocápside/metabolismo , Proteínas del Núcleo Viral/antagonistas & inhibidores , Proteínas del Núcleo Viral/metabolismo , Ensamble de Virus , Replicación Viral , Imagen Individual de Molécula/métodos , Unión Proteica
15.
Bioengineering (Basel) ; 10(9)2023 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-37760106

RESUMEN

The structural analysis of proteins is a major domain of biomedical research. Such analysis requires resolved three-dimensional structures of proteins. Advancements in computer technology have led to progress in biomedical research. In silico prediction and modeling approaches have facilitated the construction of protein structures, with or without structural templates. In this study, we used three neural network-based de novo modeling approaches-AlphaFold2 (AF2), Robetta-RoseTTAFold (Robetta), and transform-restrained Rosetta (trRosetta)-and two template-based tools-the Molecular Operating Environment (MOE) and iterative threading assembly refinement (I-TASSER)-to construct the structure of a viral capsid protein, hepatitis C virus core protein (HCVcp), whose structure have not been fully resolved by laboratory techniques. Templates with sufficient sequence identity for the homology modeling of complete HCVcp are currently unavailable. Therefore, we performed domain-based homology modeling for MOE simulations. The templates for each domain were obtained through sequence-based searches on NCBI and the Protein Data Bank. Then, the modeled domains were assembled to construct the complete structure of HCVcp. The full-length structure and two truncated forms modeled using various computational tools were compared. Molecular dynamics (MD) simulations were performed to refine the structures. The root mean square deviation of backbone atoms, root mean square fluctuation of Cα atoms, and radius of gyration were calculated to monitor structural changes and convergence in the simulations. The model quality was evaluated through ERRAT and phi-psi plot analysis. In terms of the initial prediction for protein modeling, Robetta and trRosetta outperformed AF2. Regarding template-based tools, MOE outperformed I-TASSER. MD simulations resulted in compactly folded protein structures, which were of good quality and theoretically accurate. Thus, the predicted structures of certain proteins must be refined to obtain reliable structural models. MD simulation is a promising tool for this purpose.

16.
Antiviral Res ; 218: 105715, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37683938

RESUMEN

The core protein allosteric modulators (CpAMs) have shown great potential as highly effective antiviral drugs against hepatitis B virus (HBV) in preclinical studies and clinical trials. In this study, we evaluated a small molecule compound called QL-007, which could potentially influence capsid assembly, using HBV replicated and susceptible cell models as well as mice infected with rAAV-HBV. QL-007 significantly inhibited HBV replication in a dose-dependent manner both in vitro and in vivo, resulting in significant decreases in HBV DNA, 3.5 kb HBV RNA and HBeAg. Furthermore, QL-007 not only induced the formation of misshaped Cp149 capsids but also possessed the capability to disassemble HBV capsids. It is noteworthy that QL-007 effectively reduced cccDNA biosynthesis in de novo infections. Mechanistically, QL-007 blocked the encapsidation of pgRNA and induced aberrant polymers assembly at concentrations ≥100 nM, while having no impact on the stability of core proteins. In conclusion, our findings underscore the potential of QL-007 as an effective agent against HBV replication and introduce it as a novel CpAM for the antiviral treatment of chronic hepatitis B.


Asunto(s)
Virus de la Hepatitis B , Hepatitis B , Animales , Ratones , Cápside , Ensamble de Virus , Proteínas del Núcleo Viral/genética , Proteínas de la Cápside/metabolismo , Antivirales/uso terapéutico , Replicación Viral
17.
Bioorg Med Chem Lett ; 94: 129456, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37633618

RESUMEN

Disruption of the HBV capsid assembly process through small-molecule interaction with HBV core protein is a validated target for the suppression of hepatitis B viral replication and the development of new antivirals. Through combination of key structural features associated with two distinct series of capsid assembly modulators, a novel aminochroman-based chemotype was identified. Optimization of anti-HBV potency through generation of SAR in addition to further core modifications provided a series of related functionalized aminoindanes. Key compounds demonstrated excellent cellular potency in addition to favorable ADME and pharmacokinetic profiles and were shown to be highly efficacious in a mouse model of HBV replication. Aminoindane derivative AB-506 was subsequently advanced into clinical development.


Asunto(s)
Antivirales , Proteínas de la Cápside , Cápside , Animales , Ratones , Antivirales/farmacología , Modelos Animales de Enfermedad , Relación Estructura-Actividad , Virus de la Hepatitis B/efectos de los fármacos , Virus de la Hepatitis B/metabolismo
18.
Asian Biomed (Res Rev News) ; 17(1): 3-12, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37551202

RESUMEN

Recent advances in human immunodeficiency virus (HIV) diagnostics have improved the management of disease progression significantly, which have also boosted the efficacy of antiviral therapies. The detection of HIV at the earliest is very important. A highly recognized and effective virological biomarker for acute HIV infections is p24 antigen. This brief overview is based on advances of HIV diagnosis while focusing on the latest HIV testing technologies including HIV-specific antigens detecting assays of both anti-HIV antibodies and p24 antigen. In addition to other emerging molecular diagnostics for acute HIV infection, the utilization of p24 antigen has been summarized. Moreover, it has been explained how these immunoassays have reduced the window period for detection of HIV in the acute stage of infection.

19.
Ann Diagn Pathol ; 66: 152176, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37423116

RESUMEN

Phyllodes tumors (PTs) are biphasic fibroepithelial lesions that occur in the breast. Diagnosing and grading PTs remains a challenge in a small proportion of cases, due to the lack of reliable specific biomarkers. We screened a potential marker versican core protein (VCAN) through microproteomics analysis, validated its role for the grading of PTs by immunohistochemistry, and analyzed the correlation between VCAN expression and clinicopathological characteristics. Cytoplasmic immunoreactivity for VCAN was identified in all benign PT samples, among which 40 (93.0 %) showed VCAN-positive staining in ≥50 % of tumor cells. Eight (21.6 %) borderline PT samples showed VCAN-positive staining in ≥50 % of the cells with weak to moderate staining intensity, whereas 29 samples (78.4 %) showed VCAN-positive staining in <50 % of the cells. In malignant PTs, 16 (84.2 %) and three (15.8 %) samples showed VCAN-positive staining in <5 % and 5-25 % of stromal cells, respectively. Fibroadenomas showed a similar expression pattern to benign PTs. Fisher's exact test showed that the percentages of positive cells (P < .001) and staining intensities (P < .001) of tumor cells were significantly different between the five groups. VCAN positivity was associated with tumor categories (P < .0001) and CD34 expression (P < .0001). The expression of VCAN gradually decreases as the tumor categories increases, following recurrence. To the best of our knowledge, our results are the first in the literature to reveal that VCAN is useful for diagnosing and grading PTs. The expression level of VCAN appeared to be negatively associated with PT categories, suggesting that dysregulation of VCAN may be involved in the tumor progression of PTs.


Asunto(s)
Neoplasias de la Mama , Tumor Filoide , Humanos , Femenino , Tumor Filoide/patología , Versicanos/metabolismo , Células del Estroma/patología , Mama/patología , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/metabolismo
20.
Adv Sci (Weinh) ; 10(23): e2300644, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37316966

RESUMEN

Chronic hepatitis C virus (HCV) infection is an important public health issue. However, knowledge on how the virus remodels the metabolic and immune response toward hepatic pathologic environment is limited. The transcriptomic and multiple evidences reveal that the HCV core protein-intestine-specific homeobox (ISX) axis promotes a spectrum of metabolic, fibrogenic, and immune modulators (e.g., kynurenine, PD-L1, and B7-2), regulating HCV-infection relevant pathogenic phenotype in vitro and in vivo. In a transgenic mice model, the HCV core protein-ISX axis enhance metabolic disturbance (particularly lipid and glucose metabolism) and immune suppression, and finally, chronic liver fibrosis in a high-fat diet (HFD)-induced disease model. Mechanistically, cells with HCV JFH-1 replicons upregulate ISX and, consequently, the expressions of metabolic, fibrosis progenitor, and immune modulators via core protein-induced nuclear factor-κB signaling. Conversely, cells with specific ISX shRNAi inhibit HCV core protein-induced metabolic disturbance and immune suppression. Clinically, the HCV core level is significantly correlated with ISX, IDOs, PD-L1, and B7-2 levels in HCC patients with HCV infection. Therefore, it highlights the significance of HCV core protein-ISX axis as an important mechanism in the development of HCV-induced chronic liver disease and can be a specific therapeutic target clinically.


Asunto(s)
Carcinoma Hepatocelular , Hepatitis C Crónica , Hepatitis C , Neoplasias Hepáticas , Ratones , Animales , Hepatitis C Crónica/metabolismo , Hepatitis C Crónica/patología , Antígeno B7-H1/metabolismo , Hepatitis C/metabolismo , Ratones Transgénicos , Progresión de la Enfermedad
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