Affiliation:
1. Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605
Abstract
ABSTRACT
The glycan shield comprised of multiple carbohydrate chains on the human immunodeficiency virus (HIV) envelope glycoprotein gp120 helps the virus to evade neutralizing antibodies. The present study describes a novel method for increasing immunogenicity of gp120 vaccine by enzymatic replacement of sialic acid on these carbohydrate chains with Galα1-3Galβ1-4GlcNAc-R (α-gal) epitopes. These epitopes are ligands for the natural anti-Gal antibody constituting ∼1% of immunoglobulin G in humans. We hypothesize that vaccination with gp120 expressing α-gal epitopes (gp120
αgal
) results in in vivo formation of immune complexes with anti-Gal, which targets vaccines for effective uptake by antigen-presenting cells (APC), due to interaction between the Fc portion of the antibody and Fcγ receptors on APC. This in turn results in effective transport of the vaccine to lymph nodes and effective processing and presentation of gp120 immunogenic peptides by APC for eliciting a strong anti-gp120 immune response. This hypothesis was tested in α-1,3-galactosyltransferase knockout mice, which produce anti-Gal. Mice immunized with gp120
αgal
produced anti-gp120 antibodies in titers that were >100-fold higher than those measured in mice immunized with comparable amounts of gp120 and effectively neutralized HIV. T-cell response, measured by ELISPOT, was much higher in mice immunized with gp120
αgal
than in mice immunized with gp120. It is suggested that gp120
αgal
can serve as a platform for anti-Gal-mediated targeting of additional vaccinating HIV proteins fused to gp120
αgal
, thereby creating effective prophylactic vaccines.
Publisher
American Society for Microbiology
Subject
Virology,Insect Science,Immunology,Microbiology
Cited by
73 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献