SCREENING FOR DIFFERENTIALLY EXPRESSED GENES IN DENGUE INFECTION UNDER ANTIBODY DEPENDENT ENHANCEMENT CONDITIONS

Abstract

In this study, establishment of HL-CZ (a promonocytic cell line) as a new platform for study of antibody dependent enhancement (ADE) of dengue virus infection in vitro was achieved. Characteristics of HL-CZ that enable it to support ADE were also investigated. We performed microarray gene expression profiling to compare HL-CZ cells infected with dengue virus under antibody dependent enhancement (ADE) conditions versus HL-CZ cells infected to an equivalent degree but under non-enhancing conditions. We observed differential expression of several genes belonging to the DEAD-box family of RNA helicases (DDX). These observations were confirmed at a protein level by immunoblotting for these proteins in cell lysates obtained from infected cells. Subsequent experiments employing siRNA-mediated knock-down of protein expression suggested that DDX31 and DDX47 may be crucial in supporting infection of dengue virus under ADE conditions.