Kondo Eisei, Akatsuka Yoshiki, Kuzushima Kiyotaka, Tsujimura Kunio, Asakura Shoji, Tajima Kohei, Kagami Yoshitoyo, Kodera Yoshihisa, Tanimoto Mitsune, Morishima Yasuo, Takahashi Toshitada
Division of Immunology, Aichi Cancer Center Research Institute, 1-1 Kanokoden, Chikusa-ku, Nagoya 464-8681, Japan.
Blood. 2004 Jan 15;103(2):630-8. doi: 10.1182/blood-2003-03-0824. Epub 2003 Aug 28.
Cytomegalovirus (CMV)-specific T-cell immunity plays an important role in protection from CMV disease in immunocompromised patients. Identification of cytotoxic T-lymphocyte (CTL) epitopes is essential for monitoring T-cell immunity and also for immunotherapy. In this and previous studies, CMV-pp65-specific CTL lines were successfully generated from all of 11 CMV-seropositive healthy donors, using pp65-transduced CD40-activated B (CD40-B) cells as antigen-presenting cells. By use of enzyme-linked immunospot (ELISPOT) assays, individual CTL epitopes could be mapped with truncated forms of the pp65 gene. For human leukocyte antigen (HLA) alleles with a known binding motif, CTL epitopes within the defined regions were predicted by computer algorithm. For HLA alleles without a known binding motif (HLA-Cw0801, -Cw1202, and -Cw*1502), the epitopes were alternatively identified by step-by-step truncations of the pp65 gene. Through this study, a total of 14 novel CTL epitopes of CMV-pp65 were identified. Interestingly, 3 peptides were found to be presented by 2 different HLA class I alleles or subtypes. Moreover, use of CD40-B cells pulsed with a mixture of synthetic peptides led to generation of pp65-specific CTL lines from some of seronegative donors. The study thus demonstrated an efficient strategy for identifying CTL epitopes presented by a variety of HLA alleles.
巨细胞病毒（CMV）特异性T细胞免疫在免疫功能低下患者预防CMV疾病中发挥重要作用。细胞毒性T淋巴细胞（CTL）表位的鉴定对于监测T细胞免疫以及免疫治疗都至关重要。在本研究及之前的研究中，使用pp65转导的CD40激活的B（CD40 - B）细胞作为抗原呈递细胞，成功从11名CMV血清阳性健康供者中均产生了CMV - pp65特异性CTL系。通过酶联免疫斑点（ELISPOT）测定，可利用pp65基因的截短形式定位单个CTL表位。对于具有已知结合基序的人类白细胞抗原（HLA）等位基因，通过计算机算法预测特定区域内的CTL表位。对于没有已知结合基序的HLA等位基因（HLA - Cw0801、- Cw1202和 - Cw*1502），则通过逐步截短pp65基因来鉴定表位。通过本研究，共鉴定出14个新的CMV - pp65特异性CTL表位。有趣的是，发现3种肽可由2种不同的HLA I类等位基因或亚型呈递。此外，用合成肽混合物脉冲处理的CD40 - B细胞可从一些血清阴性供者中产生pp65特异性CTL系。因此，该研究证明了一种鉴定由多种HLA等位基因呈递的CTL表位的有效策略。
