Morioka N, Kikumoto Y, Hoon D S, Morton D L, Irie R F
John Wayne Cancer Institute, Santa Monica, CA 90404.
J Immunol. 1994 Dec 15;153(12):5650-8.
The decapeptide 810 (QDLTMKYQIF) contains the antigenic epitope (KYQI) recognized by human mAb L92. This sequence is found in a 43-kDa protein associated with human melanoma M14. We examined the expression of 810 in human cells and its involvement in the cellular immune responses of melanoma patients. Nineteen stage III melanoma patients and 19 normal donors were studied for their responses to 810. All patients were immunized in vivo with an allogeneic melanoma cell vaccine. PBMC cytotoxicity was tested on autologous EBV-transformed B lymphoblastoid cell lines (BCL) pulsed with 810 and autologous melanomas. Proliferative responses of PBMC to 810 were evaluated by using [3H]Tdr incorporation assays. Western blotting revealed that the 43-kDa protein was not specific to melanoma but was common to various cells. However, the percentage of cytotoxicity of PBMC against autologous 810-pulsed BCL was significantly greater in melanoma patients than in normal controls (p < 0.005). Cytotoxicity was increased after melanoma cell vaccine immunization in 15 patients (78%). Proliferative responses to 810 were observed only in melanoma patients and were enhanced in 12 patients (63%) after vaccination. Restimulation of PBMC from vaccinated patients with 810 increased cytotoxicity against both autologous 810-pulsed BCL and melanomas. These targets were lysed by CD8+ T lymphocytes in an HLA class I-restricted manner. HLA-A2 and -A11 seemed to serve as the 810-presenting molecule. Our findings indicate that 810 may function as an epitope for CTL on human melanoma and can be used as a vaccine.
十肽810（QDLTMKYQIF）包含人单克隆抗体L92识别的抗原表位（KYQI）。该序列存在于与人类黑色素瘤M14相关的一种43 kDa蛋白中。我们检测了810在人细胞中的表达及其在黑色素瘤患者细胞免疫反应中的作用。研究了19例III期黑色素瘤患者和19名正常供体对810的反应。所有患者均接受同种异体黑色素瘤细胞疫苗的体内免疫。用810脉冲处理的自体EB病毒转化的B淋巴母细胞系（BCL）和自体黑色素瘤检测外周血单核细胞（PBMC）的细胞毒性。通过[3H]胸苷掺入试验评估PBMC对810的增殖反应。蛋白质印迹分析显示，43 kDa蛋白并非黑色素瘤所特有，而是各种细胞所共有的。然而，黑色素瘤患者PBMC对自体810脉冲处理的BCL的细胞毒性百分比显著高于正常对照（p < 0.005）。15例患者（78%）在接受黑色素瘤细胞疫苗免疫后细胞毒性增加。仅在黑色素瘤患者中观察到对810的增殖反应，12例患者（63%）在接种疫苗后反应增强。用810再次刺激接种疫苗患者的PBMC可增加对自体810脉冲处理的BCL和黑色素瘤的细胞毒性。这些靶细胞被CD8+T淋巴细胞以HLA I类限制性方式裂解。HLA-A2和-A11似乎作为810呈递分子。我们的研究结果表明，810可能作为人黑色素瘤上细胞毒性T淋巴细胞（CTL）的表位，可作为一种疫苗。
