Patta Phumesin. Inhibition of dengue virus by targeting to viral RNA. Doctoral Degree(Immunology). Mahidol University. Mahidol University Library and Knowledge Center. : Mahidol University, 2017.
Inhibition of dengue virus by targeting to viral RNA
Abstract:
Dengue virus (DENV) infection is a worldwide public health problem. It can cause a spectrum of clinical manifestations ranging from mild dengue fever (DF), severe dengue hemorrhangic fever (DHF), and potentially life-threatening disease, dengue shock syndrome (DSS). Currently, there is no availability of a specific antiviral drug for DENV infection. Thus, anti-DENV agent that can inhibit all four DENV serotypes is urgently needed. In this study, antisense oligonucleotides, vivo-morpholinos oligomers (vivo-MOs), that target to the top of 3' stem-loop (3' SL) at 3' UTR of DENV genome were tested for inhibition of DENV infection. The interaction between vivo-MOs and DENV RNA was studied by oligonucleotide binding assay. The inhibition of viral replication and production were examined in DENV-infected cell lines, including monkey kidney epithelial (Vero) cell, human lung epithelial carcinoma (A549) cells, and human immature monocyte-derived dendritic cells (MDDCs). The results of oligonulcleotide binding assay showed that vivo-MO-1 specifically bound to DENV RNA. Treatment of vivo-MO-1 significantly reduced viral RNA, viral protein, viral infectivity, and viral production in DENV-2-infected Vero cells. Furthermore, the inhibitory effect were also observed in DENV-1, 3, and 4 infected Vero cells suggesting the potential of vivo-MOs to inhibit four DENV serotypes. However, vivo-MO-1 had less activity to inhibit DENV4 infection which might be caused by 5-base pair mismatch to DENV4 genome sequence. For this reason, vivo-MO-2 was designed to completely complementary match to DENV-4 sequence. As expected, the result showed that vivo-MO-2 had greater inhibitory activity than vivo-MO-1 to inhibit viral production and viral infection in DENV-4 infected Vero cells. The vivo-MOs activity has been testes in other target cell types, A549 and MDDCs. The results showed that vivo-MOs were effectively inhibited viral infection and viral production in DENV-2 infected A549 cells. Furthermore, vivo-MOs significantly reduced viral RNA, viral protein, viral infection and viral production in DENV-2 infected MDDCs. Taken together, vivo-MOs at submicromolar concentration was nontoxic and sufficient to effectively inhibit DENV infection in Vero cells, A549 cells, and MDDCs. This study supports further development of vivo-MOs as anti-DENV inhibitors targeting to DENV RNA.