Characterization of the infectivity of an Indonesian Zika virus strain in mammalian cell lines

Objective:To characterize the infection patterns and growth characteristics of the Zika virus(ZIKV)strain JMB-185 from Indonesia in various mammalian cell lines.Methods:ZIKV was grown in human(A549,HEK293,HepG2,Huh7,Jurkat,and THP-1)and non-human mammalian(RAW264.7,Vero,and Vero76)cell lines.Viral replication kinetics were measured using plaque assay,while intra-and extracellular viral RNA concentrations were assessed using RT-PCR.Flow cytometry was used to quantify the infected cells and cell viability was measured using an MTT assay.The ability of ZIKV to infect cell lines was visualized using a fluorescence immunostaining assay.Results:This ZIKV strain preferentially infected the lung,kidney,and liver cell lines A549,HEK293,Huh7,Vero,and Vero76,but not the immune cells Jurkat,RAW264.7,and THP-1.By contrast,the ZIKV showed no sign of infection in HepG2 cells,while maintaining viral titer over 3 days post-infection,with no infection recorded in immunostaining,no increase in viral RNA,and no indication of cell deterioration.Conclusions:The Indonesian ZIKV strain has a similar infection profile as other strains,except for its poor infectivity on HepG2 cells.Information on the growth characteristics of Indonesia ZIKV will help expand our understanding of the biology of ZIKV which will be useful for various applications including antiviral discovery.

Modifiable determinants of attitude towards dengue vaccination among healthy inhabitants of Aceh,Indonesia:Findings from a community-based survey

Objective:To explore and understand the attitude towards dengue vaccination and its modifiable determinants among inhabitants of Aceh(northern Sumatra Island,Indonesia),the region that was most severely affected by the earthquake and tsunami of 26 December 2004.Methods:A communitybased,cross-sectional study was conducted among 535 healthy inhabitants in nine regencies(Kabupaten or Kotamadya) of Aceh that were selected randomly from November 2014 to March 2015.A set of validated,pre-tested,structured questionnaires was used to guide the interviews.The questionnaires covered a range of explanatory variables and one outcome variable(attitude to dengue vaccination).Multi-step logistic regression analysis and Spearman's rank correlation were used to test the role of explanatory variables for the outcome variable.Results:More than 70%of the participants had a poor attitude towards dengue vaccination.Modifiablc determinants associated with poor attitude to dengue vaccination were low education level,working as farmers and traditional market traders,low socioeconomic status and poor knowledge,attitude and practice regarding dengue fever(P<0.05).The KAP domain scores were correlated strongly with attitude to dengue vaccination,r_s=0.25,r_S=0.67 and r_s=0.20,respectively(P<0.001).Multivariate analysis found that independent predictors associated with attitude towards dengue vaccination among study participants were only sex and attitude towards dengue fever(P<0.001).Conclusions:This study reveals that low KAP regarding dengue fever,low education level and low socioeconomic status are associated with a poor attitude towards dengue vaccination.Therefore,inhabitants of suburbs who are working as larmers or traditional market traders with low socioeconomic status are the most appropriate target group for a dengue vaccine introduction program.

Inhibitory Effect of Alpha‑Mangostin to Dengue Virus Replication and Cytokines Expression in Human Peripheral Blood Mononuclear Cells

Massive pro-inflammatory cytokines production has been correlated with the pathogenesis of severe dengue disease.The active compound of mangosteen fruit pericarps,α-mangostin,has been commonly used as traditional medicine and dietary supplement.We examined the effect ofα-mangostin against dengue virus(DENV)infection in human peripheral blood mononuclear cells(PBMC)by the measurement of virus titer and TNF-αand IFN-γcytokines concentration post infection.Increasing concentration ofα-mangostin inhibited virus replication and reduced inflammatory cytokines expression at 24-and 48-h post infection.Our results support the potential use ofα-mangostin as anti-antiviral and anti-inflammatory therapies in the treatment of dengue.