Ranieri E, Herr W, Gambotto A, Olson W, Rowe D, Robbins P D, Kierstead L S, Watkins S C, Gesualdo L, Storkus W J
Departments of Surgery, Pittsburgh, Pennsylvania 15261, USA.
J Virol. 1999 Dec;73(12):10416-25. doi: 10.1128/JVI.73.12.10416-10425.1999.
Epstein-Barr virus (EBV) is a herpesvirus commonly associated with several malignancies, particularly in immunocompromised hosts. As a strategy for stimulating immunity against EBV for the treatment of EBV-associated tumors, we have genetically engineered dendritic cells (DC) to express EBV antigens, such as latent membrane protein 2B (LMP2B), using recombinant adenovirus vectors. CD8(+) T lymphocytes from HLA-A2.1(+), EBV-seropositive healthy donors were cultured with autologous DC infected with recombinant adenovirus vector AdEGFP, encoding an enhanced green fluorescent protein (EGFP), or AdLMP2B at a multiplicity of infection of 250. After 48 h, >95% of the DC were positive for EGFP expression as assessed by fluorescence-activated cell sorting analysis, indicating efficient gene transfer. AdLMP2-transduced DC were used to stimulate CD8(+) T cells. Responder CD8(+) T cells were tested for gamma interferon (IFN-gamma) release by enzyme-linked spot (ELISPOT) assay and cytotoxic activity. Prior to in vitro stimulation, the frequencies of T-cells directed against two HLA-A2-presented LMP2 peptides (LMP2 329-337 and LMP2 426-434) were very low as assessed by IFN-gamma spot formation (T-cell frequency, <0.003%). IFN-gamma ELISPOT assays performed at day 14 showed a significant (2-log) increase of the day 0 frequency of T cells reactive against the LMP2 329-337 peptide, from 0.003 to 0.3 (P < 0.001). Moreover, specific cytolytic activity was observed against the autologous EBV B-lymphoblastoid cell lines after 21 days of stimulation of T-cell responders with AdLMP2-transduced DC (P < 0.01). In summary, autologous mature DC genetically modified with an adenovirus encoding EBV antigens stimulate the generation of EBV-specific CD8(+) effector T cells in vitro, supporting the potential application of EBV-based adenovirus vector vaccination for the immunotherapy of the EBV-associated malignancies.
爱泼斯坦-巴尔病毒(EBV)是一种疱疹病毒,通常与多种恶性肿瘤相关,尤其是在免疫功能低下的宿主中。作为刺激针对EBV的免疫以治疗EBV相关肿瘤的一种策略,我们利用重组腺病毒载体对树突状细胞(DC)进行基因工程改造,使其表达EBV抗原,如潜伏膜蛋白2B(LMP2B)。将来自HLA-A2.1(+)、EBV血清学阳性健康供体的CD8(+) T淋巴细胞与感染了编码增强型绿色荧光蛋白(EGFP)的重组腺病毒载体AdEGFP或AdLMP2B的自体DC以感染复数250进行培养。48小时后,通过荧光激活细胞分选分析评估,>95%的DC为EGFP表达阳性,表明基因转移效率高。用AdLMP2转导的DC刺激CD8(+) T细胞。通过酶联免疫斑点(ELISPOT)测定法和细胞毒性活性检测应答性CD8(+) T细胞的γ干扰素(IFN-γ)释放。在体外刺激之前,通过IFN-γ斑点形成评估,针对两种HLA-A2呈递的LMP2肽(LMP2 329-337和LMP2 426-434)的T细胞频率非常低(T细胞频率,<0.003%)。在第14天进行的IFN-γ ELISPOT测定显示,对LMP2 329-337肽有反应的T细胞在第0天的频率显著(2个对数)增加,从0.003增加到0.3(P < 0.001)。此外,在用AdLMP2转导的DC刺激T细胞应答者21天后,观察到针对自体EBV B淋巴母细胞系的特异性细胞溶解活性(P < 0.01)。总之,用编码EBV抗原的腺病毒进行基因改造的自体成熟DC在体外刺激产生EBV特异性CD8(+)效应T细胞,支持基于EBV的腺病毒载体疫苗接种在EBV相关恶性肿瘤免疫治疗中的潜在应用。