The aim of this study was to design a high
density multiepitope protein, which can be
a promising multiepitope vaccine candidate
against Hepatitis E virus (HEV). Initially, conserved
and antigenic helper T-lymphocyte
(HTL) epitopes in the HEV capsid protein were
predicted by in silico analysis. Subsequently, a
multiepitope comprising four HTL epitopes
with high-affinity binding to the HLA molecules
was designed, and repeated four times as high
density multiepitope construct. This construct
was synthesized and cloned into pET-30a (þ)
vector. Then, it was transformed and expressed
in Escherichia coli BL21 cells. The high
density multiepitope protein was purified by
Ni-NTA agarose and concentrated using Amicon
filters. Finally, the immunological properties
of this high density multiepitope protein
were evaluated in vitro. The results showed
that the high density multiepitope construct
was successfully expressed and purified. SDSPAGE
and Western blot analyses showed the
presence of a high density multiepitope protein
band of approximately 33 kDa. Approximately
1mg of the purified protein was obtained
from each liter of the culture media. Moreover,
the purified multiepitope protein was capable
of induction of proliferation responses, IFN-g
ELISPOT responses and IFN-g and IL-12 cytokines
production in a significant level in
peripheral blood mononuclear cells (PBMCs)
isolated from HEV-recovered individuals compared
to the control group. In conclusion,
the newly produced multiepitope protein can
induce significant T helper type 1 responses in
vitro, and can be considered as a novel strategy
for the development of HEV vaccines in the
future. J. Med. Virol
