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Objective@#To investigate the inhibitory effect of bortezomib (PS-341) on enterovirus replication.@*Methods@#The methyl thiazolyl tetrazolium (MTT) assay was used to value cell viability in response to PS-341 treatment. The protein and viral gene mRNAs were measured by real-time quantitative PCR (qRT-PCR).@*Results@#Our result show that after enterovirus (EV)-D68 or coxsackievirus B3 (CV-B3) infected cells were treated with PS-341, compared with the control group, the inhibition rate of the intracellular viral RNA reached 50%~70% or 60%~90%. PS-341 was added after RD cells were infectd with EV-D68, the intracellular virus titer was down-regulated by 90.23% and 83.40% in the supernatant, the intracellular virus titer was down-regulated by 93% and 90% in the supernatant and in RD cells. PS-341 had no effect on virus adsorption and importing. The cells were treated with PS-341 and apoptosis-inhibiting agent Ac-YVAD-CHO, the viral RNA replication inhibition rate reached 10%-30%, and the expression of viral protein was increased, which indicated that the inhibitory effect of PS-341 on viral replication was attenuated.@*Conclusions@#According to the result of the study, PS-341 could reduce apoptosis by regulating the proteasome pathway, inhibiting the gene replication and assemble, without effect on virus adsorption, entry and release. In addition, PS-341 also inhibited the replication of CV-B3 in cells, which suggest that PS-341 has a broad spectrum anti-EVs effects.
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Objective To analyze how enterovirus D68 (EV-D68) protease 2A affects the anti-vi-ral interferon typeⅠ(IFN-Ⅰ) pathway in 293T cells following infection. Methods Western blot was used to detect the expression of recombinant protease 2A, IFN-α and signal transducers and activators of tran-scription 1 (STAT1) at protein level. Expression of EV-D68 viral protein (VP1) and protease 2A was ana-lyzed by immunofluorescence at different time points. Cytopathic effects were recorded to calculate 50％ cell culture infective dose ( CCID50 ) . Expression of the genes involved in the anti-viral IFN-Ⅰ pathway was measured by real-time PCR (RT-PCR). Results The recombinant plasmid pCLIPf-2A was successfully constructed and the expression of recombinant protease 2A could be detected by Western blot 24 h after transfection. The recombinant protease 2A promoted the proliferation of EV-D68 at the late stage of infection and induced the production of IFN-α. Expression of the genes involved in the anti-viral IFN-Ⅰ pathway at mRNA level was up- or down-regulated to different degrees with various trends in different groups following infection. Expression of STAT1 was enhanced in all groups. Conclusions EV-D68 protease 2A promoted the activation of anti-viral IFN-Ⅰpathway in response to viral infection and enhanced the proliferation of virus at the late stage of infection.
ABSTRACT
Introducción: Los reportes de infecciones por enterovirus D68 (EV-D68) han aumentado en los últimos años. Material y métodos: Cohorte prospectiva. Se realizó la búsqueda de EV-D68 en niños internados en el Hospital de Pediatría Juan P. Garrahan entre 1-5-2016 y 30-9-2016 con: infección respiratoria aguda baja (IRAB) que requirieran cuidados intensivos, parálisis aguda fláccida (PAF) asimétrica con compromiso de sustancia gris en resonancia magnética nuclear (RMN) o identificación de cualquier enterovirus con cuadro clínico compatible. La identificación de EV-D68 se realizó en el Servicio de Neurovirus, Instituto Nacional de Enfermedades Infecciosas INEI-ANLIS "Dr. CG. Malbrán". Resultados: n: 6. PAF: cuatro niños presentaron PAF asimétrica, con arreflexia y RMN compatible con mielitis. Requirieron ventilación mecánica en unidades de cuidados intensivos (UCI) dos de los 4 niños. Todos presentaron parálisis residual. Se identificó EV-D68 en secreciones nasofaríngeas (SNF) de todos ellos. En líquido cefalorraquídeo sólo en uno. Miocarditis: Una niña sana de 5 años se internó en UCI por disfunción miocárdica y fiebre. Presentaba además derrame pericárdico moderado. Recibió gamaglobulina e.v. con buena evolución. En SNF se identificaron virus sincicial respiratorio (VSR) y EV-D68. IRAB grave: se identificó EV-D68 en un paciente de 14 meses que permaneció en UCI por IRAB grave con requerimientos de ventilación no invasiva por 72 hs, con buena evolución posterior. Se constató coinfección VSR y EV-D68 en SNF. Conclusiones: Se reportan 6 pacientes internados con infección por EV-D68. La vigilancia epidemiológica activa es esencial para identificar la circulación, las características clínicas y el pronostico de las infecciones por virus emergentes (AU)
Introduction: Reports on enterovirus D68 (EV-D68) infections have increased over the past years. Material and methods: A prospective cohort study. A search for EV-D68 infection was conducted in children hospitalized at Hospital de Pediatría Juan P. Garrahan between 1-5-2016 and 30-9-2016 with: acute lower respiratory infection (ALRI) requiring intensive care unit (UCI) admission, acute flaccid paralysis (AFP), asymmetry with grey matter involvement on magnetic resonance imaging (MRI), or identification of any enterovirus associated with compatible features. The identification of EV-D68 was performed at the Department of Neuroviruses of the InstitutoNacional de EnfermedadesInfecciosas INEI-ANLIS "Dr. CG. Malbrán". Results: n: 6. AFP: four children had asymmetric AFP with areflexia and MRI compatible with myelitis. Two of four required mechanical ventilation in the ICU. All of them presented with residual paralysis. EV-D68 was identified in the nasopharyngeal swab (NPS) in all of them and in the cerebrospinal fluid in only one. Myocarditis: A 5-year-old healthy girl was admitted to the ICU because of myocardial dysfunction and fever associated with moderate pericardial effusion. She was put on IV gamma globulin with a good response. In the NPS respiratory syncytial virus (RSV) and EV-D68 were identified. Severe ALRI: EV-D68 was identified in a 14-month-old patient who was admitted to the UCU because of severe ALRI requiring non-invasive ventilation for 72 hours with a good outcome. A RSV and EV-D68 coinfection was found in the NPS. Conclusions: We report six inpatients with a EV-D68 infection. Active epidemiological surveillance is crucial to identify circulation of the virus, clinical features, and prognosis of emerging viruses (AU)