Clustered epitopes within a new poly-epitopic HIV-1 DNA vaccine shows immunogenicity in BALB/c mice

Abstract

Despite a huge number of studies towards vaccine development against human immunodeficiency virus-1, no effective vaccine has been approved yet. Thus, new vaccines should be provided with new formulations. Herein, a new DNA vaccine candidate encoding conserved and immunogenic epitopes from HIV-1 antigens of tat, pol, gag and env is designed and constructed. After bioinformatics analyses to find the best epitopes and their tandem, nucleotide sequence corresponding to the designed multiepitope was synthesized and cloned into pcDNA3.1+ vector. Expression of pcDNA3.1-tat/pol/gag/env plasmid was evaluated in HEK293T cells by RT-PCR and western-blotting. Seven groups of BALB/c mice were intramuscularly immunized three times either with 50, 100, 200 µg of plasmid in 2-week intervals or with similar doses of insert-free plasmid. Two weeks after the last injection, proliferation of T cells and secretion of IL4 and IFN-γ cytokines were evaluated using Brdu and ELISA methods, respectively. Results showed the proper expression of the plasmid in protein and mRNA levels. Moreover, the designed multiepitope plasmid was capable of induction of both proliferation responses as well as IFN-γ and IL-4 cytokine production in a considerable level compared to the control groups. Overall, our primary data warranted further detailed studies on the potency of this vaccine.

Granulocyte‐macrophage colony‐stimulating factor, a potent adjuvant for polarization to Th‐17 pattern: an experience on HIV‐1 vaccine model

“…Immunization with vaccine/GM‐CSF increased lymphoproliferative activity. Considering that lymphocyte proliferation reflects the cellular immune responses , this finding confirms that GM‐CSF stimulates T lymphocytes as reported by many researchers . Cellular immune responses have important role in the clearing of viral infected cells via killing by CTLs or activating Th1 platform .…”

“…In the previous study, HIV-1 tat/pol/gag/env expression plasmid and also recombinant HIV-1 tat/pol/gag/env protein were produced (10). Murine GM-CSF expression plasmid was kindly provided by Dr. Young-Chul Sung.…”

“…Cytokine‐encoding plasmids not only increase antigen‐specific immune responses but can also alter the Th1/Th2 cytokine balance and thereby immune response polarization . However, controlling HIV‐1 infection needed both humoral and cellular immune responses that provide sterilizing immunity over a prolonged period . However, recent studies have shown that Th‐17 cytokine level and also it balance to regulatory T cells have important role for controlling AIDS disease progression .…”

Adjuvant Effect of Royal Jelly on HIV-1 Multi-Epitope Vaccine Candidate: Induction of Th1 Cytokine Pattern

“…Recombinant HIV-1 tat/pol/gag/env protein was produced in E coli BL21 DE3 as reported previously [24]. The vaccine was absorbed on Alum adjuvant and then mixed with 10, 50 or 100 µg of Royal jelly.…”

Post-Genomics and Vaccine Improvement for Leishmania

“…If dominant, these peptides will affect the immune response. To avoid junctional peptides, spacers such as AAA ( Jafarpour et al, 2014 ), AAY ( Huebener et al, 2008 ), K ( Li et al, 2005 ) and AD ( Bazhan et al, 2010 ) for CD8 + T cell epitopes and GPGPG for CD4 + T cell epitopes ( Moise et al, 2011 ) are recommended. Spacers starting with “A” are more frequently used with respect to the “P1 premise.” Accordingly, the chance of proteasomal cleavage increases once the P1 amino acid next to the C-terminal peptide is alanine ( Neisig et al, 1995 ).…”