Haglund Karl, Leiner Ingrid, Kerksiek Kristen, Buonocore Linda, Pamer Eric, Rose John K
Department of Pathology, Program in Microbiology, Yale University School of Medicine, New Haven, Connecticut 06510, USA.
J Virol. 2002 Aug;76(15):7506-17. doi: 10.1128/jvi.76.15.7506-7517.2002.
We investigated long-term memory and recall cellular immune responses to human immunodeficiency virus type 1 (HIV-1) Env and Gag proteins elicited by recombinant vesicular stomatitis viruses (VSVs) expressing Env and Gag. More than 7 months after a single vaccination with VSV-Env, approximately 6% of CD8(+) splenocytes stained with major histocompatibility complex class I tetramers containing the Env p18-I10 immunodominant peptide and showed a memory phenotype (CD44(Hi)). The level of tetramer-positive cells in memory was about 14% of the peak primary response. Recall responses elicited in these mice 5 days after boosting with a heterologous recombinant vaccinia virus expressing HIV-1 Env showed that 40 to 45% of CD8(+) splenocytes were tetramer positive and activated (CD62L(Lo)), and these cells produced gamma interferon after stimulation with Env peptide, indicating that they were functional. Five months after the boost, the long-term memory cell population (tetramer positive, CD44(Hi)) constituted 30% of the CD8(+) splenocytes. Recall responses to HIV-1 Gag were examined in mice primed with VSV recombinants expressing HIV-1 Gag protein and boosted with a vaccinia virus recombinant expressing Gag. Using this protocol, we found that approximately 40% of CD8(+) splenocytes were activated (CD62L(Lo)) and specific for a Gag immunodominant peptide (tetramer positive). The high-level Gag recall response elicited by the vaccinia virus-Gag was greater than that obtained by boosting with a VSV-Gag vector with a different VSV glycoprotein. The corresponding levels of CD44(Hi) memory cells were also higher long after boosting with vaccinia virus-Gag than after boosting with a glycoprotein exchange VSV-Gag. Our results show that VSV vectors elicit high-level memory CTL responses and that these can be amplified as much as six- to sevenfold using a heterologous boosting vector.
我们研究了由表达Env和Gag的重组水疱性口炎病毒（VSV）引发的针对1型人类免疫缺陷病毒（HIV-1）Env和Gag蛋白的长期记忆和回忆性细胞免疫反应。用VSV-Env单次接种疫苗7个多月后，约6%的CD8(+)脾细胞被含有Env p18-I10免疫显性肽的主要组织相容性复合体I类四聚体染色，并呈现记忆表型（CD44(Hi)）。记忆中四聚体阳性细胞的水平约为初次应答峰值的14%。在用表达HIV-1 Env的异源重组痘苗病毒加强免疫5天后，这些小鼠引发的回忆反应显示，40%至45%的CD8(+)脾细胞四聚体呈阳性且被激活（CD62L(Lo)），并且这些细胞在用Env肽刺激后产生γ干扰素，表明它们具有功能。加强免疫5个月后，长期记忆细胞群体（四聚体阳性，CD44(Hi)）占CD8(+)脾细胞的30%。在先用表达HIV-1 Gag蛋白的VSV重组体免疫并用表达Gag的痘苗病毒重组体加强免疫的小鼠中检测了对HIV-1 Gag的回忆反应。使用该方案，我们发现约40%的CD8(+)脾细胞被激活（CD62L(Lo)）且对Gag免疫显性肽具有特异性（四聚体阳性）。痘苗病毒-Gag引发的高水平Gag回忆反应大于用具有不同VSV糖蛋白的VSV-Gag载体加强免疫所获得的反应。在用痘苗病毒-Gag加强免疫后很长时间，相应水平的CD44(Hi)记忆细胞也高于用糖蛋白交换的VSV-Gag加强免疫后的水平。我们的结果表明VSV载体可引发高水平的记忆性CTL反应，并且使用异源加强载体可将这些反应放大六至七倍。
