IMMUNOBIOLOGY OF CUTANEOUS T CELL LYMPHOMA

皮肤T细胞淋巴瘤（CTCL）是一种T细胞克隆性恶性肿瘤， 有明显的渗透表皮的倾向， 它们被认为是正常细胞的特征 来源：CD 4+（辅助/诱导）、CD 45 RO+（记忆）和CLA+（皮肤 淋巴样抗原）。 本供资期间提出的意见 表明另外两种CTCL细胞膜分子， 恶性克隆特有的小肽，也具有显著的 重要性 恶性T细胞上的I类结合肽是强的 肿瘤特异性抗原的候选者，以及大量展示的 糖蛋白BE 2与热休克蛋白的成员同源 70（hsp 70）家族，被认为加速肽抗原转移到 I类主要组织相容性复合体（MHC）分子。 作为体内 针对I类MHC相关抗原的抗CTCL免疫应答 大量的非恶性CD 8 + T细胞表明， 在早期斑块期CTCL病变中，通过CD 8 + T细胞的能力， 选择性裂解自体CTCL细胞，并通过CTCL细胞展示， I类MHC沟中的独特肽。 由于CD 8 + T细胞 在I类MHC的背景下识别肽，值得注意的是， 单采血液疗法仅在那些 红皮病CTCL患者保持正常水平的CD 8 + T细胞， 支持天然CD 8 + T细胞介导的抗CTCL的可能性， 可以在治疗上增强反应。 在这个项目中，一级- 将洗脱区分CTCL细胞的相关肽， 测序;这些肽的起源细胞质蛋白将被 鉴定;和肽作为靶点的能力， 将测定抗肿瘤CD 8 + T细胞应答。 第一，净化 白血病细胞群将根据其 已经确定的单个抗V β（T细胞受体或 TCR）家族特异性单克隆抗体。 这些新鲜获得的CTCL 细胞将作为待表征肽的主要来源。 此外，将衍生杂交瘤细胞系，其中CTCL细胞 贡献了表达的I类MHC和TCR膜蛋白， 自体CD 8+抗CTCL细胞，从血液和病变中提取 患者将被传播。 第二，从溶解的CTCL细胞， 独特的I类MHC相关肽将被洗脱，亲和力 柱纯化，通过HPLC分析并与已知的序列进行比较。 蛋白质，以确定其细胞质分子的起源。 的 这些肽使自体B淋巴母细胞敏感的能力 还将检查自体抗CTCL CD 8 + T细胞的裂解。 第三，BE 2抗原的高表达对大肠癌细胞增殖的意义。 CTCL细胞的表面将在同源性的背景下进行探索。 在这个分子和热休克蛋白70之间，热休克蛋白70是一个已知具有 重要的免疫功能和能够陪伴肿瘤 实验系统中的特异性肽抗原。 的结构 CTCL衍生的BE 2以及BE 2结合的小肽将更容易被发现。 这些BE 2结合肽的能力， 使自体靶细胞对特异性抗肿瘤溶解敏感也将 下定决心。 总之，这些研究应有助于改善 了解CTCL细胞肽加工和免疫原性。

Cutaneous T cell lymphoma (CTCL) is a clonal malignancy of T cells with a marked propensity to infiltrate epidermis and a phenotype characteristic of the normal cells from which they are thought to be derived: CD4+ (helper/inducer), CD45RO+ (memory) and CLA+ (cutaneous lymphoid antigen). Observations made during the current funding period suggest that two other CTCL cell membrane molecules, capable of housing small peptides distinctive to malignant clones, are also of substantial importance. Class I bound peptides on the malignant T cells are strong candidates for tumor specific antigens, and the abundantly displayed glycoprotein BE2 is homologous with members of the heat shock protein 70(hsp70) family, thought to expedite transfer of peptide antigens to class I major histocompatibility complex (MHC) molecules. As in vivo anti-CTCL immune response directed against class I MHC-associated peptides is suggested by the large number of nonmalignant CD8+ T cells in early plaque stage CTCL lesions, by the capacity of CD8+ T cells to selectively lyse autologous CTCL cells and by CTCL cell display of distinctive peptides in the groove of class I MHC. Since CD8+ T cells recognize peptides in the context of class I MHC, it is noteworthy that photopheresis produces longstanding remissions in only those erythrodermic CTCL patients who retain normal levels of CD8+ T cells, supporting the possibility that a natural CD8+ T cell mediated anti-CTCL response can be therapeutically enhanced. In this project, class I- associated peptides which distinguish CTCL cells will be eluted and sequenced; the cytoplasmic proteins of origin of these peptides will be identified; and the capacity of the peptides to serve as targets for anti-tumor CD8+ T cell responses will be determined. First, purified populations of leukemic cell will be isolated on the basis of their already established binding of individual anti-Vbeta (T cell receptor or TCR) family specific monoclonal antibodies. These freshly obtained CTCL cells will serve as the principal source of peptides to be characterized. In addition, hybridoma cell lines will be derived in which CTCL cells contribute the expressed class I MHC and TCR membrane proteins, and lines of autologous CD8+ anti-CTCL cells, extracted form blood and lesions of patients, will be propagated. Second, from solubilized CTCL cells, distinctive class I MHC-associated peptides will be eluted, affinity column purified, analyzed by HPLC and compared to sequences of known proteins to determine their cytoplasmic molecules of origin. The capacity of these peptides to sensitize autologous B lymphoblasts to lysis by autologous anti-CTCL CD8+ T cells will also be examined. Third, the significance of the abundant expression of BE2 antigen on the surface of CTCL cells will be explored in the context of the homology between this molecule and hsp70, a family of proteins known to have important immunologic functions and to be capable of chaperoning tumor specific peptide antigens in experimental systems. The structure of CTCL-derived BE2, as well as of BE2-bound small peptides, will be more firmly delineated, and the capacity of these BE2-bound peptides to sensitize autologous target cells for specific anti-tumor lysis will also be determined. Together, these studies should facilitate an improved understanding of CTCL cell peptide processing and immunogenicity.