Liu Y, Chiriva-Internati M, Grizzi F, Salati E, Roman J J, Lim S, Hermonat P L
Departments of Obstetrics and Gynecology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA.
Cancer Gene Ther. 2001 Dec;8(12):948-57. doi: 10.1038/sj.cgt.7700391.
We have shown that the pulsing of dendritic cells (DCs) with human papillomavirus type 16 (HPV-16) antigen proteins by lipofection stimulates class I-restricted cytotoxic T lymphocyte (CTL) response against primary cervical cancer cells. Also, we have shown that adeno-associated virus (AAV) was able to effectively deliver a cytokine gene into DCs. It has been our hypothesis that the delivery of antigen genes into DCs, resulting in endogenous and continuous antigen protein expression, may result in an improvement in T-cell priming by DCs. Here, DCs are pulsed (infected) with an AAV vector containing the HPV-16 E6 gene. After infection, transduced E6 gene mRNA expression and vector chromosomal integration could be identified in infected DCs. Furthermore, priming rosettes formed at early times when the AAV/E6 vector was used. Most importantly, AAV/E6 vector pulsing of DCs induced, after only 7 days of priming, a strong CTL response against primary cervical cancer cell lines, compared to bacterial E6 protein lipofection. Killing was significantly blocked by the addition of anti-MHC class I antibodies. Fluorescence-activated cell sorter (FACS) analysis of resulting primed cell populations revealed higher levels of CD8+ T cells by AAV-based pulsing, with little evidence of CD56 (NK). FACS analysis of the DC populations revealed that AAV/E6 vector-pulsed DCs had higher levels of CD80 and lower levels of CD86 than protein-pulsed DCs. These data suggest that rAAV may be appropriate for antigen pulsing of DCs for immunotherapy protocols. Finally, our protocol represents an advance in regards to the time needed for generating a CTL response compared to other techniques.
我们已经证明,通过脂质转染用人乳头瘤病毒16型(HPV-16)抗原蛋白对树突状细胞(DC)进行脉冲处理,可刺激针对原发性宫颈癌细胞的I类限制性细胞毒性T淋巴细胞(CTL)反应。此外,我们还证明腺相关病毒(AAV)能够有效地将细胞因子基因传递到DC中。我们的假设是,将抗原基因传递到DC中,导致内源性和持续性抗原蛋白表达,可能会改善DC对T细胞的启动作用。在此,用含有HPV-16 E6基因的AAV载体对DC进行脉冲处理(感染)。感染后,可在受感染的DC中鉴定出转导的E6基因mRNA表达和载体染色体整合。此外,使用AAV/E6载体时,早期会形成启动花环。最重要的是,与细菌E6蛋白脂质转染相比,DC的AAV/E6载体脉冲处理仅在启动7天后就诱导出针对原发性宫颈癌细胞系的强烈CTL反应。加入抗MHC I类抗体后,杀伤作用明显受阻。对所得启动细胞群体进行的荧光激活细胞分选仪(FACS)分析显示,基于AAV的脉冲处理使CD8+ T细胞水平更高,几乎没有CD56(NK)的迹象。对DC群体的FACS分析显示,与蛋白脉冲处理的DC相比,AAV/E6载体脉冲处理的DC具有更高水平的CD80和更低水平的CD86。这些数据表明,rAAV可能适用于DC的抗原脉冲处理以用于免疫治疗方案。最后,与其他技术相比,我们的方案在产生CTL反应所需的时间方面有了进展。