Lu Y, Xiao Y, Ding J, Dierich M, Chen Y H
Laboratory of Immunology, Research Center of Medical Science and School of Life Science and Engineering, Tsinghua University, Beijing, PR China.
Int Arch Allergy Immunol. 2000 Jan;121(1):80-4. doi: 10.1159/000024300.
Based on our hypothesis that epitope vaccine may be a new strategy to induce high levels of neutralization antibodies against HIV-1, we prepared multiple-epitope vaccines using three neutralizing epitopes (GPGRAFY, RILAVERYLKD and ELDKWA) of HIV-1 gp160, and characterized their immunogenicity. Peptide 1 [C-G-(ELDKWA-GPGRAFY)(2)-K] and peptide 2 (CG-GPGRAFY-ELDKWA-G-RILAVERYLKD) were synthesized and conjugated with carrier protein bovine serum albumin (BSA). After vaccination antibody responses to these immunogens were induced and evaluated by ELISA. The C-G-(ELDKWA-GPGRAFY)(2)-K-BSA (BSA: carrier protein) multiple-epitope vaccine induced a strong antibody response to the C-G-(ELDKWA-GPGRAFY)(2)-K peptide (antibody titer: 1:25,600) and C-(ELDKWAG)(4) peptide (antibody titer: 1:12,800), but a weak antibody response to the C-(GPCGRAFY)(4) peptide. The CG-GPGRAFY-ELDKWA-G-RILAVERYLKD-K-BSA (BSA: carrier protein) multiple-epitope vaccine also induced strong antibody response to the CG-GPGRAFY-ELDKWA-G-RILAVERYLKD-K peptide (antibody titer: 1:25, 600) and C-(ELLDKWAG)(4) peptide (antibody titer: 1:6,400), a very strong response to C-(RIVALVERYLKD-G)(2)-K peptide (dilution: 1:102, 400), and a very weak response to the C-(GPGRAFY)(4) peptide (dilution: 1:400) in mice. Both antisera induced by both multiple-epitope vaccines interacted with the recombinant soluble gp41 (rgp41), but did not bind two control peptides. In comparison with both epitope vaccines, the rgp160 subunit vaccine could induce weak epitope-specific antibody response to these three epitopes on the three epitope peptides and V3, N-domain and C-domain peptides (dilution: 1:400-1:1,600). These results indicate that both multiple-epitope vaccines could induce high levels of antibodies to both neutralizing epitopes RILAVERYLKD and ELDKWA, while the GPGRAFY epitope on both vaccines appeared to have weak immunogenicity. Both multiple-epitope vaccines showed significant potency on inducing high levels of epitope-specific neutralization antibodies in comparison with rgp160 subunit vaccine.
基于我们的假设，即表位疫苗可能是诱导针对HIV-1的高水平中和抗体的一种新策略，我们使用HIV-1 gp160的三个中和表位（GPGRAFY、RILAVERYLKD和ELDKWA）制备了多表位疫苗，并对其免疫原性进行了表征。合成了肽1 [C-G-(ELDKWA-GPGRAFY)(2)-K]和肽2（CG-GPGRAFY-ELDKWA-G-RILAVERYLKD），并将其与载体蛋白牛血清白蛋白（BSA）偶联。接种疫苗后，通过ELISA诱导并评估对这些免疫原的抗体反应。C-G-(ELDKWA-GPGRAFY)(2)-K-BSA（BSA：载体蛋白）多表位疫苗对C-G-(ELDKWA-GPGRAFY)(2)-K肽（抗体效价：1:25,600）和C-(ELDKWAG)(4)肽（抗体效价：1:12,800）诱导了强烈的抗体反应，但对C-(GPCGRAFY)(4)肽的抗体反应较弱。CG-GPGRAFY-ELDKWA-G-RILAVERYLKD-K-BSA（BSA：载体蛋白）多表位疫苗对CG-GPGRAFY-ELDKWA-G-RILAVERYLKD-K肽（抗体效价：1:25,600）和C-(ELLDKWAG)(4)肽（抗体效价：1:6,400）也诱导了强烈的抗体反应，对C-(RIVALVERYLKD-G)(2)-K肽（稀释度：1:102,400）有非常强烈的反应，而对C-(GPGRAFY)(4)肽（稀释度：1:400）在小鼠中的反应非常弱。两种多表位疫苗诱导的抗血清均与重组可溶性gp41（rgp41）相互作用，但不与两种对照肽结合。与两种表位疫苗相比，rgp160亚单位疫苗对三种表位肽以及V3、N结构域和C结构域肽上的这三个表位可诱导较弱的表位特异性抗体反应（稀释度：1:400-1:1,600）。这些结果表明，两种多表位疫苗均可诱导针对中和表位RILAVERYLKD和ELDKWA的高水平抗体，而两种疫苗上的GPGRAFY表位似乎免疫原性较弱。与rgp160亚单位疫苗相比，两种多表位疫苗在诱导高水平的表位特异性中和抗体方面均显示出显著效力。
