Loomis L D, Deal C D, Kersey K S, Burke D S, Redfield R R, Birx D L
HIV Laboratory, Henry M. Jackson Foundation, Rockville, MD 20850, USA.
J Acquir Immune Defic Syndr Hum Retrovirol. 1995 Sep 1;10(1):13-26.
Humoral responses to the HIV-1 envelope were investigated in 30 human volunteers enrolled in a phase I vaccine therapy trial of rgp160 (LAI/LAV) using two techniques that emphasize detection of antibody response against linear (continuous) epitopes: immunoblotting and PEPSCAN. Seven fusion proteins containing large portions from constant regions 1, 2, 3, and 5, and variable region 3 of gp120 and two regions in the transmembrane protein, gp41, were employed in immunoblots to quantitatively measure immune response as a function of immunization. In addition, the entire gp160 (LAI/LAV) envelope protein was constructed in duplicate sets of 211 overlapping 12-mer peptides to fine-map the changes. Immunoblotting defined significant changes in reactivity to epitopes in constant regions; of 28 volunteers completing the trial, the percentage with reactivity against C1 changed from 62 to 100%; for C2, from 0 to 46%; for C3, from 0 to 82%; and for a constant region in gp41, from 25 to 68%. PEPSCAN on a subset (n = 8) of these volunteers identified new reactivity to epitopes throughout the envelope, concentrated in V1, C3, and C5 in gp120 and several peptides in gp41. Completely immunized patients responded to double the number of linear epitopes compared with two patients receiving alum alone. The results verify that the response to rgp160 is significantly broadened after immunization, providing additional evidence that HIV-1-infected volunteers can expand their antibody repertoire against a protein from a pathogen during chronic infection with that same pathogen. These results expand those previously obtained in this patient cohort, by defining explicitly the immunogenic regions recognized postvaccination and by providing methodology for quantitating those changes.
在一项使用两种强调检测针对线性（连续）表位的抗体反应技术的I期rgp160（LAI/LAV）疫苗治疗试验中，对30名人类志愿者的HIV-1包膜体液反应进行了研究：免疫印迹法和肽扫描法。免疫印迹中使用了七种融合蛋白，这些融合蛋白包含gp120恒定区1、2、3和5的大部分以及可变区3，以及跨膜蛋白gp41中的两个区域，以定量测量免疫反应作为免疫接种的函数。此外，构建了211个重叠的12肽重复两组的完整gp160（LAI/LAV）包膜蛋白，以精细定位变化。免疫印迹法确定了对恒定区表位反应性的显著变化；在完成试验的28名志愿者中，对C1有反应性的百分比从62%变为100%；对C2，从0变为46%；对C3，从0变为82%；对gp41中的一个恒定区，从25%变为68%。对这些志愿者的一个子集（n = 8）进行的肽扫描法确定了整个包膜中对表位的新反应性，集中在gp120的V1、C3和C5以及gp41中的几个肽段。与仅接受明矾的两名患者相比，完全免疫的患者对线性表位的反应数量增加了一倍。结果证实，免疫后对rgp160的反应显著拓宽，提供了额外的证据表明，HIV-1感染的志愿者在感染同一病原体的慢性感染过程中，可以扩大其针对病原体蛋白的抗体库。这些结果扩展了之前在该患者队列中获得的结果，明确了疫苗接种后识别的免疫原性区域，并提供了定量这些变化的方法。
