Antibody-dependent enhancement representing in vitro infective progeny virus titer correlates with the viremia level in dengue patients

ABSTRACTDengue virus (DENV) distributes throughout tropical and subtropical countries and causes dengue fever (DF) and dengue hemorrhagic fever in humans. Some DF patients suddenly develop severe symptoms after the defervescent period. Although the pathogenic mechanism of the severe symptoms has not been fully elucidated, the viremia level in the early phase has been shown to correlate with the disease severity. One of the hypotheses is that a phenomenon called antibody-dependent enhancement (ADE) of infection leads to a high level of viremia. To examine the plausibility of this hypothesis, we examined the relationship between in vitro ADE activity and in vivo viral load quantity in six patients with dengue diseases. An autologous DENV strain was isolated from each of the six patients. Blood samples were then collected at multiple time points between the acute and defervescent phases, and the balance between neutralizing and enhancing activities against the autologous and prototype viruses was examined. As the antibody levels against DENV were rapidly increased, ADE activity was decreased over time or partially maintained against some viruses at low serum dilution. In addition, positive correlations were observed between ADE activity representing in vitro progeny virus production and viremia levels in patient plasma samples. Therefore, the measurement of ADE activity in dengue-seropositive samples may help to predict the impact of viral load in the subsequent DENV infection.IMPORTANCEIt has not been fully elucidated how the phenomenon of antibody-dependent enhancement (ADE) affects the pathogenesis of severe dengue diseases, although high viremia levels have been epidemiologically demonstrated to be associated with the disease severity. Here, we show that ADE in the acute-phase patient sera exhibited significantly different activities against autologous and lab strains than ADE in the defervescent-phase sera. Further, the enhancement of progeny virus production activity, which is one of the factors to evaluate ADE in vitro, was significantly correlated with the levels of viral load in the patient blood circulation. This suggests that measurement of the in vitro enhancing progeny virus titers might be used to predict the impact of in vivo DENV viremia level. Our present findings could contribute to a method to forecast disease severity for seropositive populations who would be at risk of developing severe disease in the event of heterotypic DENV infection.

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Antibody-dependent enhancement representing in vitro infective progeny virus titer correlates with the viremia level in dengue patients

Scientific Reports ◽

10.1038/s41598-021-91793-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Atsushi Yamanaka ◽

Hisham Ahmed Imad ◽

Weerapong Phumratanaprapin ◽

Juthamas Phadungsombat ◽

Eiji Konishi ◽

...

Keyword(s):

Viral Load ◽

Virus Titer ◽

Virus Production ◽

Hemorrhagic Fever ◽

Progeny Virus ◽

Multiple Time ◽

Antibody Dependent Enhancement ◽

Viremia Level

AbstractDengue virus (DENV) causes dengue fever (DF) and dengue hemorrhagic fever in humans. Some DF patients suddenly develop severe symptoms around the defervescent period. Although the pathogenic mechanism of the severe symptoms has not been fully elucidated, the viremia level in the early phase has been shown to correlate with the disease severity. One of the hypotheses is that a phenomenon called antibody-dependent enhancement (ADE) of infection leads to high level of viremia. To examine the plausibility of this hypothesis, we examined the relationship between in vitro ADE activity and in vivo viral load quantity in six patients with dengue diseases. Blood samples were collected at multiple time points between the acute and defervescent phases, and the balance between neutralizing and enhancing activities against the autologous and prototype viruses was examined. As the antibody levels against DENV were rapidly increased, ADE activity was decreased over time or partially maintained against some viruses at low serum dilution. In addition, positive correlations were observed between ADE activity representing in vitro progeny virus production and viremia levels in patient plasma samples. The measurement of ADE activity in dengue-seropositive samples may help to predict the level of viral load in the subsequent DENV infection.

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Improving the Biocontrol Potential of Bacterial Antagonists with Salicylic Acid against Brown Rot Disease and Impact on Nectarine Fruits Quality

Agronomy ◽

10.3390/agronomy11020209 ◽

2021 ◽

Vol 11 (2) ◽

pp. 209

Author(s):

Nadia Lyousfi ◽

Rachid Lahlali ◽

Chaimaa Letrib ◽

Zineb Belabess ◽

Rachida Ouaabou ◽

...

Keyword(s):

Salicylic Acid ◽

Disease Severity ◽

Mycelial Growth ◽

Brown Rot ◽

Antagonistic Bacteria ◽

Biological Treatments ◽

Rot Disease ◽

The Impact

The main objective of this study was to evaluate the ability of both antagonistic bacteria Bacillus amyloliquefaciens (SF14) and Alcaligenes faecalis (ACBC1) used in combination with salicylic acid (SA) to effectively control brown rot disease caused by Monilinia fructigena. Four concentrations of salicylic acid (0.5%, 2%, 3.5%, and 5%) were tested under in vitro and in vivo conditions. Furthermore, the impact of biological treatments on nectarine fruit parameters’ quality, in particular, weight loss, titratable acidity, and soluble solids content, was evaluated. Regardless of the bacterium, the results indicated that all combined treatments displayed a strong inhibitory effect on the mycelial growth of M. fructigena and disease severity. Interestingly, all SA concentrations significantly improved the biocontrol activity of each antagonist. The mycelial growth inhibition rate ranged from 9.79% to 88.02% with the highest reduction rate recorded for bacterial antagonists in combination with SA at both concentrations of 0.5% and 3.5%. The in vivo results confirmed the in vitro results with a disease severity varying from 0.00% to 51.91%. A significant biocontrol improvement was obtained with both antagonistic bacteria when used in combination with SA at concentrations of 0.5% and 2%. The lowest disease severity observed with ACBC1 compared with SF14 is likely due to a rapid adaptation and increase of antagonistic bacteria population in wounded sites. The impact of all biological treatments revealed moderate significant changes in the fruit quality parameters with weight loss for several treatments. These results suggest that the improved disease control of both antagonistic bacteria was more likely directly linked to both the inhibitory effects of SA on pathogen growth and induced fruit resistance.

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Ginkgolic Acid Inhibits Coronavirus Strain 229E Infection of Human Epithelial Lung Cells

Pharmaceuticals ◽

10.3390/ph14100980 ◽

2021 ◽

Vol 14 (10) ◽

pp. 980

Author(s):

Maimoona Bhutta ◽

Daniel Sausen ◽

Elisa Gallo ◽

Harel Dahari ◽

Gustavo Doncel ◽

...

Keyword(s):

Influenza A ◽

Antiviral Treatment ◽

Virus Production ◽

Progeny Virus ◽

Lung Cells ◽

Viral Protein Synthesis ◽

Ginkgolic Acid ◽

Epithelial Lung Cells

Since December 2019, the COVID-19 pandemic has affected more than 200 million individuals around the globe and caused millions of deaths. Although there are now multiple vaccines for SARS-CoV-2, their efficacy may be limited by current and future viral mutations. Therefore, effective antiviral compounds are an essential component to win the battle against the family of coronaviruses. Ginkgolic Acid (GA) is a pan-antiviral molecule with proven effective in vitro and in vivo activity. We previously demonstrated that GA inhibits Herpes Simplex Virus 1 (HSV-1) by disrupting viral structure, blocking fusion, and inhibiting viral protein synthesis. Additionally, we reported that GA displays broad-spectrum fusion inhibition encompassing all three classes of fusion proteins, including those of HIV, Ebola, influenza A, and Epstein Barr virus. Here, we report that GA exhibited potent antiviral activity against Human Coronavirus strain 229E (HCoV-229E) infection of human epithelial lung cells (MRC-5). GA significantly reduced progeny virus production, expression of viral proteins, and cytopathic effects (CPE). Furthermore, GA significantly inhibited HCoV-229E even when added post-infection. In light of our findings and the similarities of this family of viruses, GA holds promising potential as an effective antiviral treatment for SARS-CoV-2.

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In Vitro Enhancement of Respiratory Syncytial Virus Infection by Maternal Antibodies Does Not Explain Disease Severity in Infants

Journal of Virology ◽

10.1128/jvi.00851-17 ◽

2017 ◽

Vol 91 (21) ◽

Cited By ~ 12

Author(s):

Elisabeth A. van Erp ◽

Puck B. van Kasteren ◽

Teun Guichelaar ◽

Inge M. L. Ahout ◽

Cornelis A. M. de Haan ◽

...

Keyword(s):

Respiratory Syncytial Virus ◽

Disease Severity ◽

Respiratory Illness ◽

Maternal Antibodies ◽

Severe Illness ◽

Antibody Dependent Enhancement ◽

Cotton Rats ◽

Syncytial Virus ◽

The Impact

ABSTRACT Respiratory syncytial virus (RSV) is the leading cause of severe respiratory illness in infants. At this young age, infants typically depend on maternally transferred antibodies (matAbs) and their innate immune system for protection against infections. RSV-specific matAbs are thought to protect from severe illness, yet severe RSV disease occurs mainly below 6 months of age, when neutralizing matAb levels are present. To investigate this discrepancy, we asked if disease severity is related to antibody properties other than neutralization. Some antibody effector functions are mediated via their Fc binding region. However, it has been shown that this binding may lead to antibody-dependent enhancement (ADE) of infection or reduction of neutralization, both possibly leading to more disease. In this study, we first showed that high levels of ADE of RSV infection occur in monocytic THP-1 cells in the presence of RSV antibodies and that neutralization by these antibodies was reduced in Vero cells when they were transduced with Fc gamma receptors. We then demonstrated that antibodies from cotton rats with formalin-inactivated (FI)-RSV-induced pulmonary pathology were capable of causing ADE. Human matAbs also caused ADE and were less neutralizing in vitro in cells that carry Fc receptors. However, these effects were unrelated to disease severity because they were seen both in uninfected controls and in infants hospitalized with different levels of RSV disease severity. We conclude that ADE and reduction of neutralization are unlikely to be involved in RSV disease in infants with neutralizing matAbs. IMPORTANCE It is unclear why severity of RSV disease peaks at the age when infants have neutralizing levels of maternal antibodies. Additionally, the exact reason for FI-RSV-induced enhanced disease, as seen in the 1960s vaccine trials, is still unclear. We hypothesized that antibodies present under either of these conditions could contribute to disease severity. Antibodies can have effects that may lead to more disease instead of protection. We investigated two of those effects: antibody-dependent enhancement of infection (ADE) and neutralization reduction. We show that ADE occurs in vitro with antibodies from FI-RSV-immunized RSV-infected cotton rats. Moreover, passively acquired maternal antibodies from infants had the capacity to induce ADE and reduction of neutralization. However, no clear association with disease severity was seen, ruling out that these properties explain disease in the presence of maternal antibodies. Our data contribute to a better understanding of the impact of antibodies on RSV disease in infants.

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Platycodin D Suppresses Type 2 Porcine Reproductive and Respiratory Syndrome Virus In Primary and Established Cell Lines

Viruses ◽

10.3390/v10110657 ◽

2018 ◽

Vol 10 (11) ◽

pp. 657 ◽

Cited By ~ 8

Author(s):

Mingxin Zhang ◽

Taofeng Du ◽

Feixiang Long ◽

Xia Yang ◽

Yankuo Sun ◽

...

Keyword(s):

Virus Production ◽

In Vivo Studies ◽

Progeny Virus ◽

Respiratory Syndrome Virus ◽

Dependent Manner ◽

Triterpenoid Saponins ◽

Platycodin D

Porcine reproductive and respiratory syndrome virus (PRRSV) is a continuous threat to the pork industry as it continues to cause significant economic loss worldwide. Currently, vaccination strategies provide very limited protection against PRRSV transmission. Consequently, there is an urgent need to develop new antiviral strategies. Platycodin D (PD) is one of the major bioactive triterpenoid saponins derived from Platycodon grandiflorum, a traditional Chinese medicine used as an expectorant for pulmonary diseases and a remedy for respiratory disorders. Here, we demonstrate that PD exhibits potent activity against PRRSV infection in Marc-145 cells and primary porcine alveolar macrophages. PD exhibited broad-spectrum inhibitory activities in vitro against high pathogenic type 2 PRRSV GD-HD strain and GD-XH strain as well as classical CH-1a and VR2332 strains. PD at concentrations ranging 1–4 μM significantly inhibited PRRSV RNA synthesis, viral protein expression and progeny virus production in a dose-dependent manner. EC50 values of PD against four tested PRRSV strains infection in Marc-145 cells ranged from 0.74 to 1.76 μM. Mechanistically, PD inhibited PRRSV replication by directly interacting with virions therefore affecting multiple stages of the virus life cycle, including viral entry and progeny virus release. In addition, PD decreased PRRSV- and LPS-induced cytokine (IFN-α, IFN-β, IL-1α, IL-6, IL-8 and TNF-α) production in PAMs. Altogether, our findings suggested that PD is a potent inhibitor of PPRSV infection in vitro. However, further in vivo studies are necessary to confirm PD as a potential novel and effective PPRSV inhibitor in swine.

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Zika Virus-Specific IgY Results Are Therapeutic Following a Lethal Zika Virus Challenge without Inducing Antibody-Dependent Enhancement

Viruses ◽

10.3390/v11030301 ◽

2019 ◽

Vol 11 (3) ◽

pp. 301 ◽

Cited By ~ 2

Author(s):

Kyle O’Donnell ◽

Bernadette Meberg ◽

James Schiltz ◽

Matthew Nilles ◽

David Bradley

Keyword(s):

Zika Virus ◽

Denv Infection ◽

Western Hemisphere ◽

World Health ◽

Zikv Infection ◽

Antibody Dependent Enhancement ◽

Virus Challenge ◽

Health Organization

The Zika virus (ZIKV) is a newly emerged pathogen in the Western hemisphere. It was declared a global health emergency by the World Health Organization in 2016. There have been 223,477 confirmed cases, including 3720 congenital syndrome cases since 2015. ZIKV infection symptoms range from asymptomatic to Gullain–Barré syndrome and extensive neuropathology in infected fetuses. Passive and active vaccines have been unsuccessful in the protection from or the treatment of flaviviral infections due to antibody-dependent enhancement (ADE). ADE causes an increased viral load due to an increased monocyte opsonization by non-neutralizing, low-avidity antibodies from a previous dengue virus (DENV) infection or from a previous exposure to ZIKV. We have previously demonstrated that polyclonal avian IgY generated against whole-killed DENV-2 ameliorates DENV infection in mice while not inducing ADE. This is likely due to the inability of the Fc portion of IgY to bind to mammalian Fc receptors. We have shown here that ZIKV oligoclonal IgY is able to neutralize the virus in vitro and in IFNAR−/− mice. The concentration of ZIKV-specific IgY yielding 50% neutralization (NT50) was 25 µg/mL. The exposure of the ZIKV, prior to culture with ZIKV-specific IgY or 4G2 flavivirus-enveloped IgG, demonstrated that the ZIKV-specific IgY does not induce ADE. ZIKV IgY was protective in vivo when administered following a lethal ZIKV challenge in 3-week-old IFNAR−/− mice. We propose polyclonal ZIKV-specific IgY may provide a viable passive immunotherapy for a ZIKV infection without inducing ADE.

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Inosine Triphosphate Pyrophosphatase Dephosphorylates Ribavirin Triphosphate and Reduced Enzymatic Activity Potentiates Mutagenesis in Hepatitis C Virus

Journal of Virology ◽

10.1128/jvi.01087-18 ◽

2018 ◽

Vol 92 (19) ◽

Cited By ~ 7

Author(s):

Kristina Nyström ◽

Paulina H. Wanrooij ◽

Jesper Waldenström ◽

Ludmila Adamek ◽

Sofia Brunet ◽

...

Keyword(s):

Enzyme Activity ◽

Hepatitis C Virus ◽

Hepatitis C ◽

Virus Production ◽

Progeny Virus ◽

Core Antigen ◽

Naturally Occurring ◽

Genotype 2 ◽

The Impact

ABSTRACT A third of humans carry genetic variants of the ITP pyrophosphatase (ITPase) gene (ITPA) that lead to reduced enzyme activity. Reduced ITPase activity was earlier reported to protect against ribavirin-induced hemolytic anemia and to diminish relapse following ribavirin and interferon therapy for hepatitis C virus (HCV) genotype 2 or 3 infections. While several hypotheses have been put forward to explain the antiviral actions of ribavirin, details regarding the mechanisms of interaction between reduced ITPase activity and ribavirin remain unclear. The in vitro effect of reduced ITPase activity was assessed by means of transfection of hepatocytes (Huh7.5 cells) with a small interfering RNA (siRNA) directed against ITPA or a negative-control siRNA in the presence or absence of ribavirin in an HCV culture system. Low ribavirin concentrations strikingly depleted intracellular GTP levels in HCV-infected hepatocytes whereas higher ribavirin concentrations induced G-to-A and C-to-U single nucleotide substitutions in the HCV genome, with an ensuing reduction of HCV RNA expression and HCV core antigen production. Ribavirin triphosphate (RTP) was dephosphorylated in vitro by recombinant ITPase to a similar extent as ITP, a naturally occurring substrate of ITPase, and reducing ITPA expression in Huh 7.5 cells by siRNA increased intracellular levels of RTP in addition to increasing HCV mutagenesis and reducing progeny virus production. Our results extend the understanding of the biological impact of reduced ITPase activity, demonstrate that RTP is a substrate of ITPase, and may point to personalized ribavirin dosage according to ITPA genotype in addition to novel antiviral strategies. IMPORTANCE This study highlights the multiple modes of action of ribavirin, including depletion of intracellular GTP and increased hepatitis C virus mutagenesis. In cell culture, reduced ITP pyrophosphatase (ITPase) enzyme activity affected the intracellular concentrations of ribavirin triphosphate (RTP) and augmented the impact of ribavirin on the mutation rate and virus production. Additionally, our results imply that RTP, similar to ITP, a naturally occurring substrate of ITPase, is dephosphorylated in vitro by ITPase.

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The impact of Zataria multiflora Boiss extract on in vitro and in vivo Th1/Th2 cytokine (IFN-γ/IL4) balance

Journal of Ethnopharmacology ◽

10.1016/j.jep.2013.10.003 ◽

2013 ◽

Vol 150 (3) ◽

pp. 1024-1031 ◽

Cited By ~ 35

Author(s):

Mohammad Hossein Boskabady ◽

Sakine Shahmohammadi Mehrjardi ◽

Abadorrahim Rezaee ◽

Houshang Rafatpanah ◽

Sediqeh Jalali

Keyword(s):

Zataria Multiflora ◽

Th2 Cytokine ◽

Ifn Γ ◽

The Impact

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The impact of FGF19/FGFR4 signaling inhibition in antitumor activity of multi-kinase inhibitors in hepatocellular carcinoma

Scientific Reports ◽

10.1038/s41598-021-84117-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Hiroaki Kanzaki ◽

Tetsuhiro Chiba ◽

Junjie Ao ◽

Keisuke Koroki ◽

Kengo Kanayama ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Molecular Mechanisms ◽

Kinase Inhibitors ◽

Progression Free Survival ◽

Erk Signaling ◽

Enzyme Linked Immunosorbent Assay ◽

Antitumor Effects ◽

The Impact

AbstractFGF19/FGFR4 autocrine signaling is one of the main targets for multi-kinase inhibitors (MKIs). However, the molecular mechanisms underlying FGF19/FGFR4 signaling in the antitumor effects to MKIs in hepatocellular carcinoma (HCC) remain unclear. In this study, the impact of FGFR4/ERK signaling inhibition on HCC following MKI treatment was analyzed in vitro and in vivo assays. Serum FGF19 in HCC patients treated using MKIs, such as sorafenib (n = 173) and lenvatinib (n = 40), was measured by enzyme-linked immunosorbent assay. Lenvatinib strongly inhibited the phosphorylation of FRS2 and ERK, the downstream signaling molecules of FGFR4, compared with sorafenib and regorafenib. Additional use of a selective FGFR4 inhibitor with sorafenib further suppressed FGFR4/ERK signaling and synergistically inhibited HCC cell growth in culture and xenograft subcutaneous tumors. Although serum FGF19high (n = 68) patients treated using sorafenib exhibited a significantly shorter progression-free survival and overall survival than FGF19low (n = 105) patients, there were no significant differences between FGF19high (n = 21) and FGF19low (n = 19) patients treated using lenvatinib. In conclusion, robust inhibition of FGF19/FGFR4 is of importance for the exertion of antitumor effects of MKIs. Serum FGF19 levels may function as a predictive marker for drug response and survival in HCC patients treated using sorafenib.

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Transcriptional Profiling of Porcine Blastocysts Produced In Vitro in a Chemically Defined Culture Medium

Animals ◽

10.3390/ani11051414 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1414

Author(s):

Josep M. Cambra ◽

Emilio A. Martinez ◽

Heriberto Rodriguez-Martinez ◽

Maria A. Gil ◽

Cristina Cuello

Keyword(s):

Culture Medium ◽

Embryo Quality ◽

Transcriptional Profiling ◽

Defined Medium ◽

Platelet Factor ◽

Defined Media ◽

Defined Culture ◽

The Impact

The development of chemically defined media is a growing trend in in vitro embryo production (IVP). Recently, traditional undefined culture medium with bovine serum albumin (BSA) has been successfully replaced by a chemically defined medium using substances with embryotrophic properties such as platelet factor 4 (PF4). Although the use of this medium sustains IVP, the impact of defined media on the embryonic transcriptome has not been fully elucidated. This study analyzed the transcriptome of porcine IVP blastocysts, cultured in defined (PF4 group) and undefined media (BSA group) by microarrays. In vivo-derived blastocysts (IVV group) were used as a standard of maximum embryo quality. The results showed no differentially expressed genes (DEG) between the PF4 and BSA groups. However, a total of 2780 and 2577 DEGs were detected when comparing the PF4 or the BSA group with the IVV group, respectively. Most of these genes were common in both in vitro groups (2132) and present in some enriched pathways, such as cell cycle, lysosome and/or metabolic pathways. These results show that IVP conditions strongly affect embryo transcriptome and that the defined culture medium with PF4 is a guaranteed replacement for traditional culture with BSA.

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