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Differences in type I interferon signaling antagonism by dengue viruses in human and non-human primate cell lines.

Medina FA, Torres-Malavé G, Chase AJ, Santiago GA, Medina JF, Santiago LM, Muñoz-Jordán JL - PLoS Negl Trop Dis (2015)

Bottom Line: The ability of DENVs to inhibit IFN-α/β signaling is conserved.Although some variation in the inhibition was observed, the moderate differences may be difficult to correlate with clinical outcomes.DENVs were unable to inhibit pSTAT1 in NHP cell lines, but their ability to inhibit pSTAT1 in primary Rhesus macaque dendritic cells suggests that this may be a cell specific phenomena or due to the transformed nature of the cell lines.

View Article: PubMed Central - PubMed

Affiliation: Centers for Disease Control and Prevention, Division of Vector-Borne Diseases, Dengue Branch, San Juan, Puerto Rico, United States of America.

ABSTRACT

Background/objectives: In vitro studies have shown that dengue virus (DENV) can thwart the actions of interferon (IFN)-α/β and prevent the development of an antiviral state in infected cells. Clinical studies looking at gene expression in patients with severe dengue show a reduced expression of interferon stimulated genes compared to patients with dengue fever. Interestingly, there are conflicting reports as to the ability of DENV or other flaviviruses to inhibit IFN-α/β signaling.

Methodology/principal findings: In order to determine the relative inhibition of IFN-α/β signaling by DENVs, a method combining flow cytometry and a four-parameter logistic regression model was established. A representative isolate from DENV-1, -3 and -4 and seventeen representative isolates encompassing all DENV-2 genotypes were evaluated. All of the DENVs evaluated in this study were capable of inhibiting IFN-α/β signaling. Most of the strains were able to inhibit IFN-α/β to a degree similar to DENV strain 16681; however, DENV-2 sylvatic strains demonstrated an increased inhibition of phosphorylated signal transducer and activator of transcription (pSTAT1). Surprisingly, we were unable to observe inhibition of pSTAT1 by DENV-2 sylvatic strains or the Asian strain 16681 in non-human primate (NHP) cell lines. Analysis in primary Rhesus macaque dendritic cells suggests that DENVs are capable of inhibiting IFN signaling in these cells. However, contrary to human dendritic cells, production of IFN-α was detected in the supernatant of DENV-infected Rhesus macaque dendritic cells.

Conclusions: The ability of DENVs to inhibit IFN-α/β signaling is conserved. Although some variation in the inhibition was observed, the moderate differences may be difficult to correlate with clinical outcomes. DENVs were unable to inhibit pSTAT1 in NHP cell lines, but their ability to inhibit pSTAT1 in primary Rhesus macaque dendritic cells suggests that this may be a cell specific phenomena or due to the transformed nature of the cell lines.

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Related in: MedlinePlus

Comparison of DENV replication in A549 cells detected by RT-PCR.A549 cells were infected with representative DENV strains at an MOI = 0.1 for 1 hour. After washing, cells were incubated for the time period indicated (12, 24, 48, or 72 h) and cell supernatants were harvested for quantification of viral genomes by real-time RT-PCR as described in Materials and Methods. Experiments were performed in triplicate. Results shown are representative of two independent experiments.
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pntd.0003468.g004: Comparison of DENV replication in A549 cells detected by RT-PCR.A549 cells were infected with representative DENV strains at an MOI = 0.1 for 1 hour. After washing, cells were incubated for the time period indicated (12, 24, 48, or 72 h) and cell supernatants were harvested for quantification of viral genomes by real-time RT-PCR as described in Materials and Methods. Experiments were performed in triplicate. Results shown are representative of two independent experiments.

Mentions: The replication rate of all the DENVs used in this study was measured to determine if it could play a role in the observed IFN-α/β antagonism of these viruses. Only DENV-1 displayed lower growth than the other three DENV serotypes (Fig. 4A). However, the level of pSTAT1 inhibition of DENV-1 was not as low as DENV-3, which displayed a similar replication rate as DENV-4, the best pSTAT1 inhibitor. Measurement of the replication rate of DENV-2 strains showed that the Asian strains replicated to higher levels than American/Asian and American strains (Figs. 4B, 3C, 3D & 3E). The replications rates of strains in the Cosmopolitan and sylvatic genotypes were variable and inconsistent within the genotype (Fig. 4E & 4F). DENV DkD811 displayed one of the lowest replication rates. Together, the data demonstrates that the replication rate of DENVs does not cause interference in our model assessing the IFN inhibitory ability of these viruses.


Differences in type I interferon signaling antagonism by dengue viruses in human and non-human primate cell lines.

Medina FA, Torres-Malavé G, Chase AJ, Santiago GA, Medina JF, Santiago LM, Muñoz-Jordán JL - PLoS Negl Trop Dis (2015)

Comparison of DENV replication in A549 cells detected by RT-PCR.A549 cells were infected with representative DENV strains at an MOI = 0.1 for 1 hour. After washing, cells were incubated for the time period indicated (12, 24, 48, or 72 h) and cell supernatants were harvested for quantification of viral genomes by real-time RT-PCR as described in Materials and Methods. Experiments were performed in triplicate. Results shown are representative of two independent experiments.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4359095&req=5

pntd.0003468.g004: Comparison of DENV replication in A549 cells detected by RT-PCR.A549 cells were infected with representative DENV strains at an MOI = 0.1 for 1 hour. After washing, cells were incubated for the time period indicated (12, 24, 48, or 72 h) and cell supernatants were harvested for quantification of viral genomes by real-time RT-PCR as described in Materials and Methods. Experiments were performed in triplicate. Results shown are representative of two independent experiments.
Mentions: The replication rate of all the DENVs used in this study was measured to determine if it could play a role in the observed IFN-α/β antagonism of these viruses. Only DENV-1 displayed lower growth than the other three DENV serotypes (Fig. 4A). However, the level of pSTAT1 inhibition of DENV-1 was not as low as DENV-3, which displayed a similar replication rate as DENV-4, the best pSTAT1 inhibitor. Measurement of the replication rate of DENV-2 strains showed that the Asian strains replicated to higher levels than American/Asian and American strains (Figs. 4B, 3C, 3D & 3E). The replications rates of strains in the Cosmopolitan and sylvatic genotypes were variable and inconsistent within the genotype (Fig. 4E & 4F). DENV DkD811 displayed one of the lowest replication rates. Together, the data demonstrates that the replication rate of DENVs does not cause interference in our model assessing the IFN inhibitory ability of these viruses.

Bottom Line: The ability of DENVs to inhibit IFN-α/β signaling is conserved.Although some variation in the inhibition was observed, the moderate differences may be difficult to correlate with clinical outcomes.DENVs were unable to inhibit pSTAT1 in NHP cell lines, but their ability to inhibit pSTAT1 in primary Rhesus macaque dendritic cells suggests that this may be a cell specific phenomena or due to the transformed nature of the cell lines.

View Article: PubMed Central - PubMed

Affiliation: Centers for Disease Control and Prevention, Division of Vector-Borne Diseases, Dengue Branch, San Juan, Puerto Rico, United States of America.

ABSTRACT

Background/objectives: In vitro studies have shown that dengue virus (DENV) can thwart the actions of interferon (IFN)-α/β and prevent the development of an antiviral state in infected cells. Clinical studies looking at gene expression in patients with severe dengue show a reduced expression of interferon stimulated genes compared to patients with dengue fever. Interestingly, there are conflicting reports as to the ability of DENV or other flaviviruses to inhibit IFN-α/β signaling.

Methodology/principal findings: In order to determine the relative inhibition of IFN-α/β signaling by DENVs, a method combining flow cytometry and a four-parameter logistic regression model was established. A representative isolate from DENV-1, -3 and -4 and seventeen representative isolates encompassing all DENV-2 genotypes were evaluated. All of the DENVs evaluated in this study were capable of inhibiting IFN-α/β signaling. Most of the strains were able to inhibit IFN-α/β to a degree similar to DENV strain 16681; however, DENV-2 sylvatic strains demonstrated an increased inhibition of phosphorylated signal transducer and activator of transcription (pSTAT1). Surprisingly, we were unable to observe inhibition of pSTAT1 by DENV-2 sylvatic strains or the Asian strain 16681 in non-human primate (NHP) cell lines. Analysis in primary Rhesus macaque dendritic cells suggests that DENVs are capable of inhibiting IFN signaling in these cells. However, contrary to human dendritic cells, production of IFN-α was detected in the supernatant of DENV-infected Rhesus macaque dendritic cells.

Conclusions: The ability of DENVs to inhibit IFN-α/β signaling is conserved. Although some variation in the inhibition was observed, the moderate differences may be difficult to correlate with clinical outcomes. DENVs were unable to inhibit pSTAT1 in NHP cell lines, but their ability to inhibit pSTAT1 in primary Rhesus macaque dendritic cells suggests that this may be a cell specific phenomena or due to the transformed nature of the cell lines.

Show MeSH
Related in: MedlinePlus