Background: Vaccine against HIV-1 is not currently available. In present, Virus like particles
(VLPs) as effective strategy was used in several vaccine developing. Two conserved sequences;
V3 loop of gp120 and the membrane-proximal external region (MPER) of gp41 are dominant
sites for vaccine studies.
Objective: In this study, we used fusion gene of MPER and V3 to product recombinant VLPs and
introduced a novel retroviral VLPs harboring high copy of MPER-V3 for HIV-1 vaccine design.
Methods: The pEGFP-N1 plasmid harboring MPER-V3 sequence with Vpr linker was constructed.
To produce virus-like particles, HEK 293T cells were co-transfected with the recombinant plasmid,
pSPAX-2, pMD2-G and pWPXLd plasmids, evaluated by AFM and SEM microscopy and quantified
using P24 end-point ELISA assay.
Results: Time-course quantification of p24 protein as the characteristics of viral production evidenced
for the efficient secretion of virus-like structures (up to 120 ng/ml) to the culture supernatant
of transfected cells. Examination of the centrifuge-concentrated VLPs by AFM and SEM microscope,
also illustrated particles with spherical morphologies and diameters of around 150 nm that
had similar sizes to HIV virions.
Conclusion: These data indicated the production of HIV-1 virus-like particles harboring high copy
of MPER-V3 that maintained their antigenic structure. These VLPs represented a good implication
as a potential vaccine candidate and this guarantees the further investigations towards the assessment
of its immunogenicity.