Related Experiment Video
Updated: Jun 27, 2026

Utilizing the Antigen Capsid-Incorporation Strategy for the Development of Adenovirus Serotype 5-Vectored Vaccine Approaches
Published on: May 6, 2015
Designed recombinant adenovirus type 5 vector induced envelope-specific CD8(+) cytotoxic T lymphocytes and
Takehiro Ura1, Atsushi Yoshida, Ke-Qin Xin
1Department of Molecular Biodefence Research, Yokohama City University Graduate School of Medicine, Yokohama, Japan.
Background:
A monoclonal antibody (mAb) 2F5 binds to the membrane-proximal external region (MPER) of the transmembrane subunit gp41 of human immunodeficiency virus type 1 (HIV-1) is known to broadly neutralize HIV-1 strains. The Adenovirus type 5 vector (Ad5) has been widely applied for HIV-1 vaccine, and hexon hypervariable region 5 (HVR5) is exposed on viral surface and easily target host immune responses against Ad5.
Methods:
We constructed a recombinant adenovirus type 5 vector (rAd5) with a 2F5-binding epitope (ELDKWA) of MPER on Ad5-HVR5. In addition, we developed rAd5 encoding the HIV-1(IIIB) envelope (Env) gene for the induction of Env-specific cellular immunity.
Results:
The virus titers of the constructed rAd5 were similar to that of the parental Ad5 vector. Furthermore, high-dose immunization of rAd5 induced Env-specific CD8(+) cells and high levels of anti-ELDKWA antibodies. Moreover, an in vitro HIV-1 neutralization assay indicated that ELDKWA-specific mAbs derived from rAd5-immunized mice neutralized a wide range of HIV-1 strains.
Conclusions:
The present study outlines the development of an Ad5-based HIV-1 vaccine targeting the hypervariable regions of Ad5. The constructed rAd5 induced an HIV-1-specific cellular immune response and neutralizing antibodies against various strains of HIV-1 simultaneously.

