Iwakami S I, Setoguchi Y, Saijo Y, Azuma M, Fukuchi Y
Department of Respiratory Medicine, Juntendo University School of Medicine, Tokyo, Japan.
Respirology. 2001 Jun;6(2):135-44. doi: 10.1046/j.1440-1843.2001.00322.x.
Interaction between the co-stimulatory molecule B7-1 (CD80) on antigen-presenting cells and its counter-receptor CD28 on T lymphocytes plays a key role in the induction of cell-mediated immune responses. Many tumours, including lung cancer, lack expression of B7-1 and this has been suggested to contribute to the failure of immune recognition of these diseases. Based on this knowledge, we hypothesized that the co-stimulatory signal delivered through the B7-1 molecule expressed on lung cancer cells using replication deficient adenovirus vector would induce efficient tumour immunity in T lymphocytes.
To evaluate this hypothesis, we constructed two adenovirus vectors: AdCMVhB7 (an E1-deleted-Ad5-based vector containing human B7-1 cDNA driven by cytomegalovirus immediate early promoter and enhancer) and AdNull (same vector as above without expression of exogenous gene) as control. Using these adenovirus vectors, efficient generation of tumour immunity in T lymphocytes was studied using primary cultured lung cancer cells and peripheral blood lymphocytes (PBL) obtained from patients with lung cancer.
Inoculation of lung cancer cells with 10 multiplicity of infection of AdCMVhB7 resulted in rapid and efficient cell surface expression of B7-1 molecule (> 90% of cells at 24 h). Cytolytic activity of PBL in 51Cr-release assay (E/T = 40) demonstrated that effector lymphocytes induced by hB7-1 (+) lung cancer cells treated with AdCMVhB7could lyse parental lung cancer cells hB7-1 (-). In contrast, effector lymphocytes induced by lung cancer cells treated with AdNull as control virus or PBS as control could not lyse parental lung cancer cells at all. Furthermore, cytolytic activity of the effector lymphocytes induced by B7-1-transduced lung cancer cells was inhibited by addition of anti-CD3 antibody.
These data demonstrate that primary-cultured lung cancer cells treated with AdCMVhB7 would efficiently generate tumour immunity in T lymphocytes. Adenovirus-mediated-hB7-1 gene transfer may be a useful means for gene therapy of lung cancer using adoptive immunotherapy.
抗原呈递细胞上的共刺激分子B7-1（CD80）与其在T淋巴细胞上的对应受体CD28之间的相互作用在细胞介导的免疫反应诱导中起关键作用。包括肺癌在内的许多肿瘤缺乏B7-1的表达，这被认为是这些疾病免疫识别失败的原因。基于这一认识，我们推测，使用复制缺陷型腺病毒载体通过肺癌细胞上表达的B7-1分子传递的共刺激信号将在T淋巴细胞中诱导有效的肿瘤免疫。
为了评估这一假设，我们构建了两种腺病毒载体：AdCMVhB7（一种基于E1缺失的Ad5载体，包含由巨细胞病毒立即早期启动子和增强子驱动的人B7-1 cDNA）和AdNull（与上述相同但无外源基因表达的载体）作为对照。使用这些腺病毒载体，利用原发性培养的肺癌细胞和从肺癌患者获得的外周血淋巴细胞（PBL）研究了T淋巴细胞中肿瘤免疫的有效产生。
用感染复数为10的AdCMVhB7接种肺癌细胞导致B7-1分子在细胞表面快速高效表达（24小时时>90%的细胞）。在51Cr释放试验（E/T = 40）中，PBL的细胞溶解活性表明，用AdCMVhB7处理的hB7-1（+）肺癌细胞诱导的效应淋巴细胞能够裂解亲本肺癌细胞hB7-1（-）。相比之下，用作为对照病毒的AdNull或作为对照的PBS处理的肺癌细胞诱导的效应淋巴细胞根本不能裂解亲本肺癌细胞。此外，添加抗CD3抗体可抑制B7-1转导的肺癌细胞诱导的效应淋巴细胞的细胞溶解活性。
这些数据表明，用AdCMVhB7处理的原发性培养肺癌细胞将在T淋巴细胞中有效产生肿瘤免疫。腺病毒介导的hB7-1基因转移可能是采用过继性免疫疗法进行肺癌基因治疗的一种有用方法。
