Center for Retrovirus Research and Department of Veterinary Biosciences, The Ohio State University, Columbus, Ohio 43210-1093, USA.
Viral Immunol. 2009 Dec;22(6):397-405. doi: 10.1089/vim.2009.0059.
Human T-lymphotropic virus type 1 (HTLV-1) infection causes adult T-cell lymphoma/leukemia (ATL) following a prolonged clinical incubation period, despite a robust adaptive immune response against the virus. Early immune responses that allow establishment of the infection are difficult to study without effective animal models. We have developed a cytotoxic T-lymphocyte (CTL) assay to monitor the early events of HTLV-1 infection in rabbits. Rabbit skin fibroblast cell lines were established by transformation with a plasmid expressing simian virus 40 (SV40) large T antigen and used as autochthonous targets (derived from same individual animal) to measure CTL activity against HTLV-1 infection in rabbits. Recombinant vaccinia virus (rVV) constructs expressing either HTLV-1 envelope surface unit (SU) glycoprotein 46 or Tax proteins were used to infect fibroblast targets in a (51)Cr-release CTL assay. Rabbits inoculated with Jurkat T cells or ACH.2 cells (expressing ACH HTLV-1 molecule clone) were monitored at 0, 2, 4, 6, 8, 13, 21, and 34 wk post-infection. ACH.2-inoculated rabbits were monitored serologically and for viral infected cells following ex vivo culture. Proviral load analysis indicated that rabbits with higher proviral loads had significant CTL activity against HTLV-1 SU as early as 2 wk post-infection, while both low- and high-proviral-load groups had minimal Tax-specific CTL activity throughout the study. This first development of a stringent assay to measure HTLV-1 SU and Tax-specific CTL assay in the rabbit model will enhance immunopathogenesis studies of HTLV-1 infection. Our data suggest that during the early weeks following infection, HTLV-1-specific CTL responses are primarily targeted against Env-SU.
人嗜 T 细胞病毒 1 型（HTLV-1）感染在经历长期临床潜伏期后会引发成人 T 细胞淋巴瘤/白血病（ATL），尽管针对该病毒存在强大的适应性免疫反应。由于缺乏有效的动物模型，很难研究允许感染建立的早期免疫反应。我们已经开发出一种细胞毒性 T 淋巴细胞（CTL）测定法，用于监测 HTLV-1 在兔子体内感染的早期事件。通过转染表达猿猴病毒 40（SV40）大 T 抗原的质粒，建立了兔皮肤成纤维细胞系，并将其用作自体同源靶标（来自同一动物个体），以测量针对 HTLV-1 感染的 CTL 活性。表达 HTLV-1 包膜表面单位（SU）糖蛋白 46 或 Tax 蛋白的重组痘苗病毒（rVV）构建体用于在 51Cr 释放 CTL 测定中感染成纤维细胞靶标。用 Jurkat T 细胞或 ACH.2 细胞（表达 ACH HTLV-1 分子克隆）接种的兔子在感染后 0、2、4、6、8、13、21 和 34 周进行监测。监测 ACH.2 接种的兔子的血清学和体外培养后的病毒感染细胞。前病毒载量分析表明，感染后 2 周就具有较高前病毒载量的兔子对 HTLV-1 SU 具有显著的 CTL 活性，而低和高前病毒载量组在整个研究过程中对 Tax 具有最小的特异性 CTL 活性。这是首次在兔模型中开发严格测定 HTLV-1 SU 和 Tax 特异性 CTL 测定的方法，将增强对 HTLV-1 感染免疫发病机制的研究。我们的数据表明，在感染后的早期几周内，HTLV-1 特异性 CTL 反应主要针对 Env-SU。
