Immunostimulatory effects of Hsp70 fragments-modified DCs: A computational and experimental study in HIV vaccine
Elahe Akbari1, Alireza Milani1, Parisa Moradi Pordanjani1
1Department of Hepatitis and AIDS, Pasteur Institute of Iran, Tehran, Iran.
Background:
Dendritic cells (DCs) loaded with HIV-1 antigens have been explored as a promising therapeutic approach to overcome HIV-1 infection. Heat shock proteins (Hsps) can improve cross-presentation of linked antigens by DCs. Our aim was a comprehensive in silico, in vitro, and in vivo evaluation of fusion proteins comprising the N- and C-terminal regions of Hsp70 (i.e., NT-Hsp70 and CT-Hsp70) as an adjuvant linked to HIV-1 Nef antigen in development of DCs-based vaccine candidates.
Methods:
Computational analyses of the NT-Hsp70-Nef and CT-Hsp70-Nef fusion constructs were performed, and their structural features and docking ability with toll-like or endocytic receptors were evaluated. The effectiveness of DCs loaded with the fusion proteins in eliciting immunity was assessed in mice. Cytokine secretion levels from splenocytes exposed to single-cycle replicable (SCR) HIV-1 were also measured in vitro.
Results:
The DCs pulsed with the fusion constructs induced robust cellular and humoral immune responses in mice and infected splenocytes. The CT-Hsp70 region showed better docking scores with immune receptors and superior adjuvanticity for inducing Nef-specific immune responses (Th1 and CTL activity) compared to the NT-Hsp70 region in DC-based immunization.
Conclusions:
The CT-Hsp70-Nef protein demonstrated promising results in both computational and experimental analyses compared to the NT-Hsp70-Nef protein.
