T cell growth control usinghapten-specific antibody/interleukin-2receptor chimera
T cell growth control usinghapten-specific antibody/interleukin-2receptor chimera
复制标题
使用半抗原特异性抗体/白细胞介素 2 受体嵌合体控制 T 细胞生长
作者：
Sogo;T.;Kawahara;M.;Ueda;H.;Otsu;M.;Onodera;M.;Nakauchi;H. and Nagamune;T.
IL-2是活化T细胞的扩增和存活所必需的细胞因子。虽然用IL-2过继转移肿瘤特异性T细胞是癌症免疫治疗的策略之一，但在体内产生严重副作用的IL-2必须被替代。为了解决这个问题，我们提出使用抗体/IL-2 R嵌合体，其可以响应于同源抗原而抑制生长信号。将抗荧光素抗体的单链抗体分别与促红细胞生成素受体的胞外D2区和IL-2 R β或γ链的跨膜/胞浆区连接，构建了两种嵌合体。当嵌合体在IL-3依赖性前B细胞系Ba/F3和IL-2依赖性T细胞系CTLL-2中共表达时，通过添加荧光素缀合的BSA（BSA-FL）作为同源抗原，分别在不存在IL-3和IL-2的情况下选择性扩增基因修饰的细胞。生长实验表明，嵌合体细胞以BSA-FL剂量依赖性方式转导生长信号。此外，作为IL-2 R信号传导标志的STAT 3、STAT 5、ERK 1/2和Akt均被CTLL-2转染子中的嵌合体激活。我们还证明了嵌合体在鼠原代T细胞中是功能性的。这些结果表明，抗体/IL-2 R嵌合体可以基本上模拟野生型IL-2 R，并且可以在同源抗原存在下特异性扩增基因修饰的T细胞。
IL-2 is a cytokine that is essential for the expansion and survival of activated T cells. Although adoptive transfer of tumor-specific T cells with IL-2 is one of strategies for cancer immunotherapy, it is essential to replace IL-2 that exerts severe side effects in vivo. To solve this problem, we propose to use an antibody/IL-2R chimera, which can transduce a growth signal in response to a cognate antigen. We constructed two chimeras, in which ScFv of anti-fluorescein antibody was tethered to extracellular D2 domain of erythropoietin receptor and transmembrane/cytoplasmic domains of IL-2Rβ or γ chain. When the chimeras were co-expressed in IL-3-dependent pro-B cell line Ba/F3 and IL-2-dependent T cell line CTLL-2, gene-modified cells were selectively expanded in the absence of IL-3 and IL-2, respectively, by adding fluorescein-conjugated BSA (BSA-FL) as a cognate antigen. Growth assay revealed that the cells with the chimeras transduced a growth signal in a BSA-FL dose-dependent manner. Furthermore, STAT3, STAT5, ERK1/2 and Akt, which are hallmarks for IL-2R signaling, were all activated by the chimeras in CTLL-2 transfectant. We also demonstrated that the chimeras were functional in murine primary T cells. These results demonstrate that the antibody/IL-2R chimeras could substantially mimic the wild-type IL-2R and could specifically expand gene-modified T cells in the presence of the cognate antigen.