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Tryptophan 375 stabilizes the outer-domain core of gp120 for HIV vaccine immunogen design.

ABSTRACT: The outer-domain core of gp120 may serve as a better HIV vaccine immunogen than the full-length gp120 because of its greater stability and immunogenicity. In our previous report, we introduced two disulfide bonds to the outer-domain core of gp120 to fix its conformation into a CD4-bound state, which resulted in a significant increase in its immunogenicity when compared to the wild-type outer-domain core. In this report, to further improve the immunogenicity of the outer-domain core based immunogen, we have introduced a Tryptophan residue at gp120 amino acid sequence position 375 (375S/W). Our data from immunized guinea pigs indeed shows a striking increase in the immune response due to this stabilized core outer-domain. Therefore, we conclude that the addition of 375W to the outer-domain core of gp120 further stabilizes the structure of immunogen and increases the immunogenicity.

SUBMITTER: Hu D

PROVIDER: S-EPMC5440730 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

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Tryptophan 375 stabilizes the outer-domain core of gp120 for HIV vaccine immunogen design.

Hu Duoyi D Bowder Dane D Wei Wenzhong W Thompson Jesse J Wilson Mark A MA Xiang Shi-Hua SH

Vaccine 20170429 23

The outer-domain core of gp120 may serve as a better HIV vaccine immunogen than the full-length gp120 because of its greater stability and immunogenicity. In our previous report, we introduced two disulfide bonds to the outer-domain core of gp120 to fix its conformation into a CD4-bound state, which resulted in a significant increase in its immunogenicity when compared to the wild-type outer-domain core. In this report, to further improve the immunogenicity of the outer-domain core based immunog ...[more]

PMID: 28461065

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