RESUMO
Dengvaxia® (CTD-TDV), the only licensed tetravalent dengue vaccine by Sanofi Pasteur, was made available since 2015. However, administration of CTD-TDV, in general, has not received the prequalification recommendation from the World Health Organization. Having a universal antidengue agent for treatment will therefore beneficial. Accordingly, the development of nucleoside inhibitors specific to dengue viral polymerase that perturb dengue infection has been studied by many. Alternatively, we have used a marketed anti-HCV prodrug sofosbuvir to study its in silico and in vitro effects against dengue. As a result, the active metabolite of sofosbuvir (GS-461203) was predicted to bind to the catalytic motif (Gly-Asp-Asp) of dengue viral polymerase with binding affinity of -6.9 kcal/mol. Furthermore, sofosbuvir demonstrated excellent in vitro viral inhibition with an EC90 of 0.4 µm. In addition, this study demonstrated the requirement of specific liver enzymes to activate the prodrug into GS-461203 to exert its antidengue potential. All in all, sofosbuvir should be subjected to in-depth studies to provide information of its efficacy toward dengue and its lead potential as DENV polymerase inhibitor in human subjects. In conclusion, we have expended the potential of the clinically available drug sofosbuvir as treatment for dengue.
Assuntos
Antivirais/farmacologia , Vírus da Dengue/efeitos dos fármacos , Sofosbuvir/farmacologia , Motivos de Aminoácidos , Animais , Antivirais/química , Antivirais/metabolismo , Sítios de Ligação , Domínio Catalítico , Linhagem Celular , RNA Polimerases Dirigidas por DNA/química , RNA Polimerases Dirigidas por DNA/metabolismo , Vírus da Dengue/enzimologia , Humanos , Simulação de Acoplamento Molecular , Nucleosídeos/química , Pró-Fármacos/química , Pró-Fármacos/metabolismo , Pró-Fármacos/farmacologia , Ligação Proteica , Sofosbuvir/química , Sofosbuvir/metabolismo , Termodinâmica , Proteínas Virais/química , Proteínas Virais/metabolismoRESUMO
INTRODUCTION:: Infection with all serotypes of dengue virus (DV) results in augmented antigen presentation by MHC class I molecules. However, the upregulation of immunoproteasome subunits only results from infection with two serotypes. This study aims to elucidate changes in the expression of immunoproteasome subunits resulting from infection with DV, particularly DV serotype 2 (DV2). METHODS:: HepG2 cells were grown in various culture milieu. Total cellular RNA and proteins were extracted and quantified. RESULTS:: Results demonstrated sequestration of immunoproteasome subunits LMP2 and LMP7 in DV2-infected cells. CONCLUSIONS:: This study provides insights into the mechanisms underlying immune evasion by DV.
Assuntos
Vírus da Dengue/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Vírus da Dengue/classificação , Regulação da Expressão Gênica , Células Hep G2 , Humanos , Subunidades Proteicas , SorogrupoRESUMO
Abstract: INTRODUCTION: Infection with all serotypes of dengue virus (DV) results in augmented antigen presentation by MHC class I molecules. However, the upregulation of immunoproteasome subunits only results from infection with two serotypes. This study aims to elucidate changes in the expression of immunoproteasome subunits resulting from infection with DV, particularly DV serotype 2 (DV2). METHODS: HepG2 cells were grown in various culture milieu. Total cellular RNA and proteins were extracted and quantified. RESULTS: Results demonstrated sequestration of immunoproteasome subunits LMP2 and LMP7 in DV2-infected cells. CONCLUSIONS: This study provides insights into the mechanisms underlying immune evasion by DV.
Assuntos
Humanos , Vírus da Dengue/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Regulação da Expressão Gênica , Subunidades Proteicas , Vírus da Dengue/classificação , Células Hep G2 , SorogrupoRESUMO
Dengue virus (DV) infection demonstrates an intriguing virus-induced intracellular membrane alteration that results in the augmentation of major histocompatibility complex (MHC) class I-restricted antigen presentation. As oppose to its biological function in attracting CD8(+) T-cells, this phenomenon appears to facilitate the immune evasion. However, the molecular events that attribute to the dysregulation of the antigen presenting mechanism (APM) by DV remain obscure. In this study, we aimed to characterize the host cell APM upon infection with all serotypes of whole DV. Cellular RNA were isolated from infected cells and the gene expressions of LMP2, LMP7, TAP1, TAP2, TAPBP, CALR, CANX, PDIA3, HLA-A and HLA-B were analyzed via quantitative PCR. The profiles of the gene expression were further validated. We showed that all four DV serotypes modulate host APM at the proteasomal level with DV2 showing the most prominent expression profile.