Studies of the replication and growth kinetics of dengue virus in cultured mammalian and insect cells.

Abstract

Dengue virus (DENV) is the most prevalent arbovirus, being endemic in over 100 countries, with about half of the world population at risk for infection. Currently, there is no direct therapy against DENV infection and mechanism for DENV replication is not completely understood. Based on the hypothesis that culture conditions may influence the efficiency of DENV replication and progeny virion production, this study examines influence of temperature (28°C and 37°C) on DENV replication including protein synthesis, assembly and release of infectious viral particles in mammalian and mosquito cells. Western blot analysis reveals an increase in viral protein (Non-structural 3, NS3) synthesis when the temperature was elevated from 28 °C to 37 °C in both cell-types. Contrastingly, virus titers (FAID50/ml) did not increase correspondingly with the increase protein synthesis, suggesting possible defects after protein synthesis stage in viral replication cycle. The total progeny virion production was more efficient at 28 °C than 37 °C in both cell-types, indicating viral assembly affected by different temperatures. The viral secreting ratio between mammalian cells incubated at 28 °C and 37 °C is similar, suggesting that temperature may not influence viral secretion. Together, temperature influences the efficiency of DENV protein synthesis and assembly.