Desarrollo y validación de un método de suspensión basado en células Vero para la detección del virus Zika / Development and validation of a vero cell-based suspension method for the detection of Zika virus

Objetivo . Desarrollar y validar un método de suspensión celular utilizando células Vero 76 para el cultivo del virus Zika (ZIKV) basado en la infección de células recién sembradas no adheridas. Material y métodos . Se utilizaron tres multiplicidades de infección diferentes del ZIKV para desarrollar y comparar este novedoso método con el método estándar de monocapa de células confluentes. Además, validamos preliminarmente el método de suspensión utilizando muestras clínicas caracterizadas como positivas o negativas para el ZIKV. El método estándar de monocapa se utilizó como método de referencia, y el aislamiento viral se confirmó mediante un RT-PCR específico del ZIKV. Se estimó la sensibilidad e intervalos de confianza del 95% para el método de suspensión. Asimismo, se realizó una comparación técnica del método de suspensión contra el método de monocapa. Resultados . Nuestros hallazgos sugieren que tanto la carga viral como la replicación del ZIKV fueron comparables entre los métodos de infección en monocapa y en suspensión. Aunque ambos métodos fueron adecuados para cultivar y aislar el ZIKV, el método de suspensión se caracterizó por ser más fácil, barato y rápido, así como una técnica de aislamiento sensible. En comparación con el método de monocapa, el método de suspensión fue cuatro veces más sensible en la detección del ZIKV en casos inconclusos por RT-PCR. Conclusiones . El método de suspensión tiene el potencial de ser un método eficaz para cultivar y aislar el ZIKV y su uso es potencialmente útil tanto en la investigación como en entornos clínicos.

Objective. To develop and validate a cell suspension method using Vero 76 cells for culturing Zika virus (ZIKV) based on infection of detached freshly seeded cells. Material and methods. Three different multiplicities of infection of ZIKV were used to develop and compare this novel method to the standard confluent cell monolayer method. In addition, we preliminary validated the cell suspension method using well-characterized ZIKV positive and negative clinical samples. The standard confluent cell monolayer method was used as the reference method, and viral isolation was confirmed by a ZIKV-specific RT-PCR. The sensitivity and its 95% confidence intervals for the cell suspension method were estimated. Also, a technical comparison of the cell suspension method against the cell monolayer method was performed. Results. Our findings suggested that both the viral load and replication of ZIKV were comparable between both monolayer- and suspension-infection methods. Although both methods were suitable for culturing and isolating ZIKV, the cell suspension method was easier, cheaper, and quicker as well as a sensitive isolation technique. The cell suspension method was significantly more sensitive in detecting Zika in inconclusive cases by RT-PCR, with a fourfold increase compared to the confluent cell monolayer method. Conclusion. The cell suspension method has the potential to be an effective method for cultivating and isolating ZIKV and its application is potentially useful in both research and clinical settings.

Effect of cyclin D1 on HBV transcription and replication / 临床肝胆病杂志

Objective To investigate the effect of cyclin D1 (with CCND1 as the gene name) on HBV replication and its potential mechanism. Methods With reference to GSE84044 dataset, the Spearman's rank correlation analysis was used to investigate the correlation between the expression levels of genes in liver tissue and serum HBV DNA load in patients with HBV-related liver fibrosis. Cyclin D1 and cyclin D1 T286A mutant were transiently expressed in the HBV cell replication model, and time-resolved immunofluorescence and quantitative real-time PCR were used to measure the levels of HBsAg/HBeAg and HBV DNA in cell culture supernatant; Western blot was used to measure the level of HBV core protein in cells; reverse-transcription quantitative real-time PCR was used to measure the level of HBV RNA in cells; dual-luciferase reporter assay was used to observe the effect of cyclin D1 on the activity of HBV basic core promoter (BCP). GSE83148 dataset was used to investigate the correlation between CCND1 and HBV-related regulatory factors. The independent samples t -test was used for comparison of normally distributed continuous data between two groups, and the Mann-Whitney U test was used for comparison of non-normally distributed continuous data between two groups. Results The analysis of GSE84044 data showed that 7 cell cycle genes were significantly negatively correlated with HBV DNA load in liver tissue of the patients with HBV-related liver fibrosis (all r < -0.3, all P < 0.05), which included the CCND1 gene ( r =-0.474, P < 0.001). Exogenous expression of cyclin D1 and cyclin D1 T286A mutant reduced the levels of HBsAg, HBeAg, and HBV DNA in culture supernatant of the HBV replication cell model, as well as the levels of HBV core protein and HBV RNA in cells. Exogenous expression of cyclin D1 significantly inhibited the transcriptional activity of HBV BCP. The expression level of CCND1 in liver tissue of chronic hepatitis B patients was significantly positively correlated with the expression of APOBEC3G ( r =0.575, P < 0.001), SMC5 ( r =0.341, P < 0.001), and FOXM1 ( r =0.333, P < 0.001) which inhibited HBV replication, while it was significantly negatively correlated with the expression of the HBV entry receptor NTCP ( r =-0.511, P < 0.001) and HNF1α as the transcription factor for positive regulation of HBV replication ( r =-0.430, P < 0.001). Overexpression of cyclin D1 in HepG2 cells reduced the transcriptional levels of HNF1α and NTCP. Conclusion Cyclin D1 inhibits HBV transcription and replication possibly by downregulating the expression of HNF1α and NTCP.

Role of heat shock protein 90 in hepatitis B virus replication / 临床肝胆病杂志

Hepatitis B virus （HBV） has the characteristics of wide transmission， a high chronic infection rate， and a low cure rate， and improving the cure rate of HBV may help to improve the long－term prognosis of patients. Heat shock protein 90 （Hsp90） is a chaperone protein widely present in organisms. In recent years， more and more studies have shown that Hsp90 is associated with HBV infection and plays an important role in HBV replication. It can not only interact with specific proteins of the virus to promote its replication， but also interact with the host’s own proteins to perform its function. This article reviews the role of Hsp90 in HBV replication in recent studies， so as to provide new theoretical guidance and directions for the development of new anti－HBV drugs targeting Hsp90 and the prevention and treatment of HBV infection in the future.

Research advances in antiviral drugs for the treatment of hepatitis D / 临床肝胆病杂志

Hepatitis D virus (HDV) is a satellite virus of hepatitis B virus (HBV) and needs the help of HBV envelope protein to complete its own assembly and replication and then establish a new infection cycle. Chronic HDV infection is considered the most severe form of viral hepatitis, which can accelerate disease progression and increase the risk of liver cancer. Effective antiviral therapy is urgently needed to delay disease progression in patients with HDV infection, but Bulevirtide conditionally approved by European Medicines Agency in July 2020 and interferon previously recommended are the only drugs used for the treatment of HDV infection. At present, studies are being conducted for several antiviral drugs targeting viral replication cycle, and early clinical trials have obtained good results. This means that important breakthroughs have been made in the development of antiviral drugs, bringing hope for the treatment of hepatitis D. This article summarizes the current antiviral drugs for hepatitis D and discusses related treatment regimens, so as to provide a reference for the treatment of hepatitis D.

Expresión de los componentes del inflamasoma y su relación con los marcadores de riesgo cardiovascular en personas con infección por HIV-1 / Expression of the inflammasome components and its relationship with cardiovascular risk markers in people living with HIV-1

Introducción. La infección por el HIV-1 induce un estado de inflamación crónico en el que participan los inflamasomas. El incremento de los parámetros inflamatorios es mayor en individuos con replicación viral activa que en aquellos con control de la replicación viral. Este proceso desencadena alteraciones metabólicas relacionadas con cambios en el perfil lipídico, lo cual podría incrementar el riesgo de eventos cardiovasculares, incluso en pacientes con terapia antirretroviral. Objetivo. Establecer si existe correlación entre la expresión de los componentes de los inflamasomas y los marcadores de riesgo cardiovascular en individuos con control de la replicación viral y en aquellos con replicación viral activa con terapia antirretroviral o sin ella. Materiales y métodos. Se estudiaron 13 individuos con control de la replicación viral y 40 con replicación viral activa (19 sin terapia antirretroviral y 31 con terapia). Se evaluaron los marcadores clásicos de riesgo cardiovascular y se cuantificó mediante RT-PCR la expresión de los componentes de los inflamasomas (NLRP1, NLRP3, NLRC4, AIM2, ASC, IL-1ß, IL-18 y caspasa-1), TLR2, TLR4, TGF-ß e IL-10. Resultados. Se observó que los pacientes con replicación viral activa y con terapia antirretroviral presentaron un incremento en la expresión de TLR2, TLR4 e IL-18, comparados con los controladores del HIV-1. Además, mostraron grandes valores de triglicéridos y lipoproteína de muy baja densidad (Very Low Density Lipopretein, VLDL), lo que se correlaciona positivamente con la expresión de los componentes de los inflamasomas NLRP1, NLRP3, NLRC4, AIM2, ASC y caspasa-1. Conclusión. El aumento en la expresión de los componentes de los inflamasomas en los individuos con replicación viral activa y con terapia antirretroviral se correlacionó con las concentraciones de triglicéridos y VLDL, lo que sugiere el papel de la activación inmunitaria y la terapia antirretroviral en el riesgo cardiovascular.

Introduction: HIV-1 infection induces a chronic inflammatory state in which inflammasomes participate. The increase in inflammatory parameters is higher in individuals with active viral replication (progressors) than in those with viral control (HIV-1 controllers). This process triggers metabolic alterations related to changes in the lipid profile, which could increase the risk of cardiovascular events, even in patients with antiretroviral therapy. Objective: To establish whether there was a correlation between the expression of inflammasome components and cardiovascular risk markers in HIV-1 controllers and progressors with or without antiretroviral therapy. Materials and methods: We studied 13 HIV-1 controllers and 40 progressors (19 without antiretroviral therapy and 31 with therapy) and evaluated in them classic markers of cardiovascular risk. Using RT-PCR we quantified the expression of inflammasome components (NLRP1, NLRP3, NLRC4, AIM2, ASC, IL-1ß, IL-18, and caspase-1), TLR2, TLR4, TGF-ß, and IL-10. Results: Progressors with antiretroviral therapy had an increased expression of TLR2, TLR4, and IL-18 compared to HIV-1 controllers. They also showed high levels of triglycerides and VLDL, which positively correlated with the expression of the inflammasome components NLRP1, NLRP3, NLRC4, AIM2, ASC, and caspase-1. Conclusion: Progressors receiving antiretroviral therapy exhibited an increased expression of the inflammasome components, which correlated with the levels of triglycerides and VLDL. This supports the role of inflammation in cardiovascular risk during HIV-1 infection.

Replication of SARS-CoV-2 in cell lines used in public health surveillance programmes with special emphasis on biosafety

Background & objectives: Polio, measles, rubella, influenza and rotavirus surveillance programmes are of great public health importance globally. Virus isolation using cell culture is an integral part of such programmes. Possibility of unintended isolation of SARS-CoV-2 from clinical specimens processed in biosafety level-2 (BSL-2) laboratories during the above-mentioned surveillance programmes, cannot be ruled out. The present study was conducted to assess the susceptibility of different cell lines to SARS- CoV-2 used in these programmes. Methods: Replication of SARS-CoV-2 was studied in RD and L20B, Vero/hSLAM, MA-104 and Madin–Darby Canine Kidney (MDCK) cell lines, used for the isolation of polio, measles, rubella, rotavirus and influenza viruses, respectively. SARS-CoV-2 at 0.01 multiplicity of infection was inoculated and the viral growth was assessed by observation of cytopathic effects followed by real-time reverse transcription–polymerase chain reaction (qRT-PCR). Vero CCL-81 cell line was used as a positive control. Results: SARS-CoV-2 replicated in Vero/hSLAM, and MA-104 cells, whereas it did not replicate in L20B, RD and MDCK cells. Vero/hSLAM, and Vero CCL-81 showed rounding, degeneration and detachment of cells; MA-104 cells also showed syncytia formation. In qRT-PCR, Vero/hSLAM and MA-104 showed 106 and Vero CCL-81 showed 107 viral RNA copies per ?l. The 50 per cent tissue culture infectious dose titres of Vero/hSLAM, MA-104 and Vero CCL-81 were 105.54, 105.29 and 106.45/ml, respectively. Interpretation & conclusions: Replication of SARS-CoV-2 in Vero/hSLAM and MA-104 underscores the possibility of its unintended isolation during surveillance procedures aiming to isolate measles, rubella and rotavirus. This could result in accidental exposure to high titres of SARS-CoV-2, which can result in laboratory acquired infections and community risk, highlighting the need for revisiting biosafety measures in public health laboratories

SARS-CoV-2: mucho más que un virus respiratorio / SARS-COV-2: more than a respiratory virus

RESUMEN Fundamento: el virus SARS-CoV-2 es responsable de la segunda pandemia del siglo XXI. Desde su aparición en China a finales de 2019, se asocia a neumonía y considera como un virus respiratorio más. Sin embargo, durante su diseminación global demuestra su capacidad para producir daño a otros órganos con manifestaciones clínicas nunca antes descritas para otros virus respiratorios. Objetivo: describir la evidencia científica que respalde el daño extrapulmonar directo producido por el virus SARS-CoV-2 en etapas tardías de la infección, que apoyan su naturaleza bifásica y distinta frente a otros virus respiratorios. Métodos: se realizó una búsqueda de artículos referente al tema en las bases de datos MEDLINE accedido desde PubMed, SciELO y LILACS. También se tuvieron en cuenta artículos publicados en los repositorios de preimpresión como medRxiv, BioRxiv. Mediante el gestor de búsqueda y administrador de referencias Mendeley, se eliminaron los duplicados y aquellos que no se ajustaban al objetivo del estudio, se seleccionaron 63 artículos para la revisión. Resultados: la evidencia sugiere que el SARS-CoV-2 tiene tropismo no solo limitado a las vías respiratorias. La progresión clínica de la COVID-19 presenta un curso bifásico, con manifestaciones de tipo gripal en la primera fase y episodios postagudos y persistentes en la fase tardía, ocasionados por el daño directo al sistema nervioso central, cardiovascular, endocrino y renal. Conclusiones: la infección por SARS-CoV-2 no debe considerarse solo como una infección aguda y circunscrita a las vías respiratorias.

ABSTRACT Background: the SARS-CoV-2 virus is responsible for the second pandemic of the 21st century. Since its appearance in China at the end of 2019, it has been associated with pneumonia and considered to be just another respiratory virus. However, during its global spread, it shows its ability to damage other organs with clinical manifestations never before described for other respiratory viruses. Objective: to describe the scientific evidence that supports the direct extra-pulmonary damage produced by the SARS-CoV-2 virus in late stages of infection, which supports its biphasic nature and different from other respiratory viruses. Methods: a search of the articles was carried out in the MEDLINE databases accessed from PubMed, SciELO and LILACS. Articles published in prepress repositories such as medRxiv, BioRxiv were also taken into account. Using the Mendeley reference manager and search manager, duplicates and those that did not meet the objective of the study were eliminated, selecting 63 articles for the present review. Results: the evidence suggests that SARS-CoV-2 has a tropism not only limited to the respiratory tract. The clinical progression of COVID-19 presents a biphasic course, with flu-like manifestations in the first phase and post-acute and persistent episodes in the late phase, caused by direct damage to the central nervous, cardiovascular, endocrine and renal systems. Conclusions: SARS-CoV-2 infection should not be considered only as an acute infection limited to the respiratory tract.

Research on the role of miR-125b-1-3p in rotavirus replication / 中华微生物学和免疫学杂志

Objective:To investigate the role and regulatory mechanism of miR-125b-1-3p in rotavirus replication.Methods:MA104 cells were infected with rotavirus after upregulation and down-regulation of miR-125b-1-3p, respectively. The expression of miR-125b-1-3p and the copy number of rotavirus were analyzed by RT-PCR. The effect of miR-125b-1-3p on the protein expression of rotavirus was analyzed by immunofluorescence. The expression of related proteins involved in the regulation of miR-125b-1-3p was analyzed by Western blot analysis.Results:After rotavirus infection, the expression level of miR-125b-1-3p was significantly up-regulated, the copy number of VP7 and NSP3 gene of rotavirus decreased after up-regulation of miR-125b-1-3p, and the copy number of VP7 and NSP3 gene of rotavirus was significantly increased after down-regulation of miR-125b-1-3p.The fluorescence number of rotavirus protein decreased after upregulation of miR-125b-1-3p expression level, and increased after down-regulation of miR-125b-1-3p expression level. The activity of PI3K/Akt pathway was inhibited 16 h after rotavirus infection, and the up-regulation of miR-125b-1-3p could inhibit the activation of PI3K/Akt pathway.Conclusions:MiR-125b-1-3p inhibits rotavirus replication by regulating the PI3K/Akt pathway. These results provide an experimental basis for exploring the specific regulatory mechanism between miR-125b-1-3p and PI3K/Akt pathway, and provide a target for anti-infection therapy of rotavirus.

Interaction between hepatitis B virus replication and lipid metabolism in patients with chronic hepatitis B and NAFLD / 临床肝胆病杂志

There is still a large number of patients with chronic hepatitis B virus (HBV) infection in China, which greatly affects the health of Chinese people. With the change in lifestyle, the incidence rate of nonalcoholic fatty liver disease (NAFLD) is increasing year by year in China. Some clinical studies have shown that there is a relatively low incidence rate of chronic HBV infection with NAFLD, while there are still reports on NAFLD in promoting the progression of chronic hepatitis B-related diseases. Based on literature search and review, this article attempts to investigate the interaction between HBV replication, abnormal lipid metabolism, and fatty liver disease in patients with chronic hepatitis B and NAFLD, in order to provide ideas for HBV antiviral treatment and prevention of NAFLD.

Research progress of natural products against hepatitis C virus / 药学实践杂志

Hepatitis C virus (HCV) is an important factor leading to chronic hepatitis, cirrhosis and hepatocellular carcinoma. Currently, there is no vaccine available to prevent HCV infection. This article reviews the natural products with anti-HCV activity discovered from plants in recent years, and classifies and summarizes them according to their mechanism of action, in order to provide a basis for discovering anti-HCV drugs from natural products.

Effect of hsa_circ_0001613 on Zika virus replication: Preliminary study / 中国输血杂志

【Objective】 To investigate the effect of transfusion-transmitted Zika virus (ZIKV) on the expression of non-coding circular RNA (hsa_circ_0001613) and the role of hsa_circ_0001613 in Zika virus replication. 【Methods】 Human adenocarcinomic alveolar basal epithelial cells (A549) were seeded on a 12-well plate at 1.8×105/ well and infected with ZIKV at 0.05 MOI. The Total RNAs were isolated every day for 5 days after infection, and the relative expression level of hsa_circ_0001613 was detected by qRT-PCR. In addition, 10nM siRNA-hsa_circ_0001613 was transfected into 2×105/ well A549 cells to specifically knock down the expression level of hsa_circ_0001613. 24h later, the cells were infected with ZIKV (MOI=0.05). Total RNAs were isolated at day 1-5 post-infection, proteins were extracted 96h post-infection. ZIKV replication, relative host antiviral gene expression, and interferon stimulated response element (ISRE) activity were tested using qRT-PCR, western blot and dual luciferase assay, respectively. 【Results】 The relative expression of hsa_circ_0001613 decreased significantly after 1-5 days of ZIKV infection. Knockdown of hsa_circ_0001613 inhibited ZIKV replication. Meanwhile, hsa_circ_0001613 knockdown significantly upregulated IFN-α/β and its downstream interferon-stimulated genes (ISGs) expression, also increased ISRE activity. 【Conclusion】 ZIKV infection significantly suppressed hsa_circ_0001613 expression in A4549 cells. Preliminary study indicated that hsa_circ_0001613 knockdown inhibited ZIKV replication possibly through activating type-Ⅰ IFN signaling pathway as showed by increased ISGs expression and ISRE activity.

Potenciales agentes terapéuticos contra el COVID-19 basados en el bloqueo e inhibición del ciclo de vida viral y en el síndrome de tormenta de citoquinas / Potential therapeutic agents against COVID-19 based on blocking and inhibition of the viral life cycle and the cytokine storm syndrome

La pandemia de COVID-19, causada por SARS-CoV-2, es considerara la mayor emergencia sanitaria en un siglo. Clínicamente, la mayoría de los pacientes tienen síntomas leves a moderados. Sin embargo, pacientes de edad avanzada o con comorbilidades pueden desarrollar una de las complicaciones más severas de COVID-19, es decir, el síndrome de tormenta de citoquinas. Actualmente, no existen tratamientos aprobados para SARS-CoV-2. Mientras tanto, las estrategias terapéuticas se basan en la experiencia previa con otros virus. En este artículo se revisarán los diferentes agentes terapéuticos propuestos para el tratamiento de COVID-19 basados en el bloqueo e inhibición del ciclo de vida viral de SARS-CoV-2, y para el tratamiento del síndrome de tormenta de citoquinas. Se realizó una revisión narrativa mediante búsqueda en la base de datos PubMed. Entre los principales objetivos terapéuticos contra el SARS-CoV-2 están la proteína estructural principal Spike y las enzimas virales proteasa similar a la 3-quimotripsina, la proteasa viral similar a la papaína y la ARN-polimerasa dependiente de ARN. Remdesivir, un antiviral análogo a la adenosina que inhibe a la ARN-polimerasa dependiente de ARN, es considerado el fármaco más prometedor en el tratamiento de COVID-19. No obstante, su eficacia aún no se ha determinado. En el síndrome de tormenta de citoquinas, la lesión tisular causada por el virus puede inducir la producción exagerada de citoquinas proinflamatorias como la interleucina-6. Tocilizumab, un anticuerpo monoclonal que bloquea receptores de interleucina-6 y corticosteroides como la metilprednisolona pueden ser opciones terapéuticas en el tratamiento de la severidad del síndrome.

The COVID-19 pandemic, caused by SARS-CoV-2, is considered as the major health emergency in a century. Clinically, most patients have mild to moderate symptoms. Nevertheless, elderly or with comorbidities patients may develop one of the most severe complication of COVID-19, that is, the cytokine storm syndrome. Currently, there are no approved treatments for SARS-CoV-2. Meanwhile, therapeutic strategies are based on previous experience with other viruses. This article will review the different therapeutic agents proposed for the treatment of COVID-19 based on the blocking and inhibition of the viral life cycle of SARS-CoV-2, and for the treatment of cytokine storm syndrome. A narrative review was performed by searching in the PubMed database. Among the main therapeutic target against SARS-CoV-2 are the major structural protein Spike and viral enzymes 3-chymotrypsin-like protease, viral papain-like protease, and RNA-dependent RNA polymerase. Remdesivir, an adenosine analogue antiviral that inhibits RNA-dependent RNA polymerase, is considered the most promising drug in the treatment of COVID-19. Nonetheless, its efficacy has not yet been determined. In the cytokine storm syndrome, the tissue injury caused by the virus may induce the exaggerated production of pro-inflammatory cytokines such as interleukin-6. Tocilizumab, a monoclonal antibody that blocks interleukin-6 receptors, and corticosteroids such as methylprednisolone may be therapeutic options in treating the severity of the syndrome.

Novel and potent inhibitors targeting DHODH are broad-spectrum antivirals against RNA viruses including newly-emerged coronavirus SARS-CoV-2

Emerging and re-emerging RNA viruses occasionally cause epidemics and pandemics worldwide, such as the on-going outbreak of the novel coronavirus SARS-CoV-2. Herein, we identified two potent inhibitors of human DHODH, S312 and S416, with favorable drug-likeness and pharmacokinetic profiles, which all showed broad-spectrum antiviral effects against various RNA viruses, including influenza A virus, Zika virus, Ebola virus, and particularly against SARS-CoV-2. Notably, S416 is reported to be the most potent inhibitor so far with an EC of 17 nmol/L and an SI value of 10,505.88 in infected cells. Our results are the first to validate that DHODH is an attractive host target through high antiviral efficacy in vivo and low virus replication in DHODH knock-out cells. This work demonstrates that both S312/S416 and old drugs (Leflunomide/Teriflunomide) with dual actions of antiviral and immuno-regulation may have clinical potentials to cure SARS-CoV-2 or other RNA viruses circulating worldwide, no matter such viruses are mutated or not.

Novel and potent inhibitors targeting DHODH are broad-spectrum antivirals against RNA viruses including newly-emerged coronavirus SARS-CoV-2

Emerging and re-emerging RNA viruses occasionally cause epidemics and pandemics worldwide, such as the on-going outbreak of the novel coronavirus SARS-CoV-2. Herein, we identified two potent inhibitors of human DHODH, S312 and S416, with favorable drug-likeness and pharmacokinetic profiles, which all showed broad-spectrum antiviral effects against various RNA viruses, including influenza A virus, Zika virus, Ebola virus, and particularly against SARS-CoV-2. Notably, S416 is reported to be the most potent inhibitor so far with an EC of 17 nmol/L and an SI value of 10,505.88 in infected cells. Our results are the first to validate that DHODH is an attractive host target through high antiviral efficacy in vivo and low virus replication in DHODH knock-out cells. This work demonstrates that both S312/S416 and old drugs (Leflunomide/Teriflunomide) with dual actions of antiviral and immuno-regulation may have clinical potentials to cure SARS-CoV-2 or other RNA viruses circulating worldwide, no matter such viruses are mutated or not.

Novel and potent inhibitors targeting DHODH are broad-spectrum antivirals against RNA viruses including newly-emerged coronavirus SARS-CoV-2

Emerging and re-emerging RNA viruses occasionally cause epidemics and pandemics worldwide, such as the on-going outbreak of the novel coronavirus SARS-CoV-2. Herein, we identified two potent inhibitors of human DHODH, S312 and S416, with favorable drug-likeness and pharmacokinetic profiles, which all showed broad-spectrum antiviral effects against various RNA viruses, including influenza A virus, Zika virus, Ebola virus, and particularly against SARS-CoV-2. Notably, S416 is reported to be the most potent inhibitor so far with an EC of 17 nmol/L and an SI value of 10,505.88 in infected cells. Our results are the first to validate that DHODH is an attractive host target through high antiviral efficacy in vivo and low virus replication in DHODH knock-out cells. This work demonstrates that both S312/S416 and old drugs (Leflunomide/Teriflunomide) with dual actions of antiviral and immuno-regulation may have clinical potentials to cure SARS-CoV-2 or other RNA viruses circulating worldwide, no matter such viruses are mutated or not.

Regulation of p38 mitogen-activated protein kinase pathway by West Nile virus in human neuroblastoma cells / 第二军医大学学报

Objective: To explore the regulation of p38 mitogen-activated protein kinase (MAPK) pathway by West Nile virus (WNV) in human neuroblastoma SH-SY5Y cells and the contributions of p38 MAPK to WNV replication as well as stress and inflammatory response related molecule expression. Methods: Total and phosphorylated p38 MAPK levels were analyzed in SH-SY5Y cells incubated with WNV for short (5, 15, 30 and 60 min) and long (12, 24, 48 and 60 h) durations by Western blotting. Dynamic changes of CCAAT/enhancer-binding protein homologous protein (CHOP), interleukin 6 (IL-6), activating transcription factor 6α (ATF6α) and interferon-stimulated gene 15 (ISG15) mRNA expression in WNV infected cells were detected by qRT-PCR. In response to WNV infection, WNV RNA level and CHOP, IL-6, ATF6α and ISG15 mRNA levels were assessed in SH-SY5Y cells transfected with p38 MAPK siRNA. Results: Incubation with WNV for short durations enhanced p38 MAPK phosphorylation compared to the untreated control. The p38 MAPK signaling pathway was activated at 12 h and 24 h in WNV-infected SH-SY5Y cells, but down-regulated at 48 h and 60 h. WNV infection led to increased mRNA expression of CHOP, IL-6 and ISG15 and reduced ATF6α mRNA. In comparison with control siRNA transfection, the levels of WNV RNA (P<0.05) and ATF6α mRNA (P<0.01) were increased and CHOP mRNA level was decreased (P<0.05) in WNV-infected SH-SY5Y cells with the p38 MAPK siRNA transfection. Conclusion: The p38 MAPK pathway is activated during early stage of WNV infection and such activation may negatively regulate WNV replication. WNV-induced stress response molecules CHOP and ATF6α and proinflammatory cytokine IL-6 production by SH-SY5Y cells are coupled with the regulation of p38 MAPK pathway.

Research progress in host-related diagnostic markers for hepatitis B virus infection / 中华检验医学杂志

Chronic hepatitis B is caused by infection with hepatitis B virus (HBV), which can lead to the development of cirrhosis and primary hepatocellular carcinoma. Viral persistence and clinical outcomes after HBV infection depend on viral factors and host factors. With the rapid development of the invasion mechanism of HBV infection, host?related genes and proteins involved in HBV infection have been found and used as new diagnostic markers both in the treatment evaluation and prognosis of HBV infection. This review mainly introduces the clinical application and related progress of laboratory serum markers in chronic HBV infection based on host factors for optimizing clinical diagnosis.

Discovery of N-arylsulfonyl-3-acylindole benzoyl hydrazone derivatives as anti-HIV-1 agents

The discovery and development of novel inhibitors with activity against variants of human immunodeficiency virus type 1 (HIV-1) is pivotal for overcoming treatment failure. As our ongoing work on research of anti-HIV-1 inhibitors, 32 N-arylsulfonyl-3-acylindole benzoyl hydrazone derivatives were prepared by introduction of the hydrazone fragments on the N-arylsulfonyl-3-acylindolyl skeleton and preliminarily screened in vitro as HIV-1 inhibitors for the first time. Among of all the reported analogues, eight compounds exhibited significant anti-HIV-1 activity, especially N-(3-nitro)phenylsulfonyl-3-acetylindole benzoyl hydrazone (18) and N-(3-nitro)phenylsulfonyl-3-acetyl-6-methylindole benzoyl hydrazone (23) displayed the most potent anti-HIV-1 activity with EC50 values of 0.26 and 0.31 µg/mL, and TI values of >769.23 and >645.16, respectively. It is noteworthy that introduction of R3 as the methyl group and R2 as the hydrogen group could result in more potent compounds. This suggested that introduction of R3 as the methyl group could be taken into account for further preparation of these kinds of compounds as anti-HIV-1 agents

Z1, a novel DENV2 NS5 RdRp small molecular inhibitor, inhibits DENV2 replication and infection / 中国药理学通报

Aim To screen novel NS5 inhibitors a-gainst dengue virus ( DENV) replication. Methods His-tagged DENV2 NS5 RNA-dependent polymerase ( NS5 RdRp ) was expressed and purified in BL21 cells. The binding ability of the small molecules to NS5 polymerase was determined by SPR assay. The activity of dengue inhibition by Z1 was determined by CPE, LDH and plaque assay. RNA synthesis was as-sessed by Real-time PCR. The dsRNA synthesis and viral proteins were detected by immunofluorescence as-say. The level of viral proteins was examined by West-ern blot. The stage of DENV life cycle was evaluated by time of drug-addition assay. Results A small mo-lecular Z1 was discovered, which could bind to NS5 RdRp. Z1 inhibited DENV2 RNA replication, synthe-sis of dsRNA and protein synthesis in post-entry stage of dengue life-cycle. Cell based assay confirmed that Z1 inhibited DENV-induced cell death with EC50 val-ues of 4. 75μmol·L-1 . Conclusions The novel NS5 inhibitor Z1, inhibits DENV2 RNA replication, protein synthesis and release of progeny virus, which may be severed as an anti-DENV2 antiviral drug for further de-velopment.

Clinical features of 212 hepatitis B core antibody positive patients with liver injury / 中华传染病杂志

Objective To investigate the clinical features of hepatitis B core antibody (anti-HBc)positive patients with liver injury.Methods A total of 212 anti-HBc positive and HBsAg negative patients who were primarily diagnosed with liver injury from August 2013 to August 2014 at Ruijin Hospital were collected for this study.The patients were divided into cirrhosis group (n=60) and non-cirrhosis group (n =152) according to the status of cirrhosis.The 60 cases with cirrhosis were further compared with 60 cases with post-hepatitis B cirrhosis.The general information,biochemistry and immunology data were assessed.ANOVA was used to compare multiple groups of means,and Wilcoxon rank-sum test was used for non-parametric comparisons of the two groups.Results Only one case was positive for HBV DNA with the positivity rate of 0.5％.The causes for liver injury were as follows,60 cases with cryptogenic cirrhosis,which accounted for 28.3 ％;45 cases with drug-induced hepatitis,which accounted for 21.2 ％;33 cases with unexplained liver injury,which accounted for 15.6％;28 cases with acute hepatitis E,which accounted for 13.2％ and 15 cases with autoimmune hepatitis,which accounted for 7.1％.There were significant differences of T cell subpopulation,hepatitis B surface antibody (HBsAg) and hepatitis B e antibody (anti-HBe) quantitative level,red blood cells (RBC),platelet counts (PLT),prealbumin,albumin,alamine aminotransferase (ALT),aspartate transaminase (AST),international normalized ratio (INR),hyaluronic acid (HA),collagen Ⅲ (COL-Ⅲ) and collagen Ⅳ (COL-Ⅳ) between the cirrhosis group and non-cirrhosis group (all P＜0.05).The CD3+ CD4+ and CD3+ CD8+ counts,white blood cells (WBC),ALT,AST,total bilirubin (TBil) and albumin in anti-HBc-positive cirrhosis group were statistically different from those in post-hepatitis B cirrhosis group (all P＜0.05).Conclusions Some patients with positive anti-HBc still have HBV replication and infectivity.HBV anti-HBc positivity and HBsAg negativity may be associated with some cryptogenic cirrhosis and primary liver cancer.Patients with positive anti-HBc are prone to be complicated with drug-induced hepatitis,autoimmune hepatitis,and other liver damage related to immune mechanisms.Patients with cirrhosis have a higher risk to induce immune tolerance and progress to chronic disease than non-cirrhotic patients.Quantitative anti-HBc might be used as an indicator to predict disease progression after HBV infection.Disease condition in cirrhotic group with positive anti-HBc and negative HBsAg is less severe than that in post-hepatitis B cirrhosis group.