Dengue virus (DENV) is positive-sense single-stranded RNA virus of approximately 11 kb genome of the genus Flavivirus, a family Flaviviridae. It has four genetically and antigenically related viral serotypes: DENV-1, -2, -3 and -4. Flaviviruses encode a single polyprotein processed by host and viral protease to produce three structural proteins, including capsid (C) protein, precursor membrane/membrane (prM/M) and envelope (E) protein, and seven nonstructural proteins: NS1, NS2A, NS2B, NS3, NS4A, NS4B and NS5 [5] . The E protein, a 53 kDa glycoprotein important for attachment, entry, and viral envelope fusion, can bind to cellular receptors and induce neutralizing antibodies [6, 7] .