Molecular profiling of T-helper immune genes during dengue virus infection

Abstract

In this study, we provide a comprehensive molecular profiling of the involvement of T- helper (Th) genes during dengue virus infection of different cell types. The Th gene profiles of three human cell types (monocytes, T-cells and hepatocytes) were analyzed simultaneously via array-based RT-PCR upon infection with dengue virus. Differential regulation of 41 Th genes was identified and of which 20 of those genes may contribute to immuno-pathogenesis of dengue virus infection by regulating inflammation, thrombocytopenia and vascular permeability. Among the strongly up-regulated genes were the RANTES, CC-CKR3, IRF4, CLEC2C, IL-6 and TLR6, which are potent inducer of inflammation and vascular permeability. Profiling genes obtained from this study may serve as potential biomarkers and the modulation of Th immune responses during dengue virus infection has important implications in disease outcome.

Figure 1

Infectivity of human cell lines with DENV. (a) Growth curves of DENV in different human cell types. (b) Detection of DENV viral antigen (envelope protein) in different human cell types via flow cytometry analysis. All the human cells were shown to support DENV replication and high infectious virus titers were also obtained from the cells at 3 days post-infection.

Figure 2

Expression and statistical validation profiles of Th genes in dengue virus infected Jurkat cells. The differential regulation (up or down-regulated) of the 84 Th and Th-related genes upon dengue virus infection of Jurkat cells are shown. Genes with greater than 3Log₂ fold increase are indicated in the respective graphs of each cell types. The volcano plot of the RT-PCR array for each of the cell types is also provided. The plot arranges Th genes along dimensions of differential regulation (either up or down-regulation – X axis) and statistical significance (Y-axis). The higher values on the Y-axis indicate statistical significant of the up or down-regulated genes.

Figure 3

Expression and statistical validation profiles of Th genes in dengue virus infected K562 cells. The differential regulation (up or down-regulated) of the 84 Th and Th-related genes upon dengue virus infection of K562 cells are shown. Genes with greater than 3 Log₂fold increase are indicated in the respective graphs of each cell types. The volcano plot of the RT-PCR array for each of the cell types is also provided. The plot arranges Th genes along dimensions of differential regulation (either up or down-regulation – X axis) and statistical significance (Y-axis). The higher values on the Y-axis indicate statistical significant of the up or down-regulated genes.

Figure 4

Expression and statistical validation profiles of Th genes in dengue virus infected Hep G2 cells. The differential regulation (up or down-regulated) of the 84 Th and Th-related genes upon dengue virus infection of HepG2 cells are shown. Genes with greater than 3 Log₂fold increase are indicated in the respective graphs of each cell types. The volcano plot of the RT-PCR array for each of the cell types is also provided. The plot arranges Th genes along dimensions of differential regulation (either up or down-regulation – X axis) and statistical significance (Y-axis). The higher values on the Y-axis indicate statistical significant of the up or down-regulated genes.