Active Immune Therapy ot Leukemia Associated Antigens and Gene Therapy

用编码小鼠CD154的腺病毒(Ad-CD154)转导的自体CLL细胞治疗的患者 CD154)经历了白血病细胞计数和淋巴结大小的急剧下降，长期可取 作用，包括增加白血病反应性T细胞的数量，产生抗CLL抗体，以及 疾病进展的明显减慢或停止。治疗后患者非转染组旁观者的变化 CLL细胞，反映体内CD154的激活。我们发现CD154-激活诱导了一个 CLL细胞中的一系列编程事件，最初受到瞬时保护，然后敏化 通过连接诱导的外源性死亡受体(如CD95和DR5)、细胞毒药物或 抑制细胞凋亡抑制蛋白(IAP)蛋白的新型药物(见项目2)。对这些药物的敏感性 似乎与CD154激活诱导促凋亡分子表达的能力有关 Bid通过p53不依赖、c-Abl依赖的机制，显然涉及α亚型 第73页。这带来了令人兴奋的前景，即Ad-CD154基因治疗可能绕过对p53的依赖 抗白血病药物，同时诱导抗白血病细胞和抗体免疫反应。后者 已经使我们能够鉴定出一种新的CLL相关抗原，Ror1，它可能用于 检测Ad-CD154基因治疗的活性或用于本病免疫治疗的疫苗。 在未来的临床研究中，我们开发了一种人源化的CD154(命名为ISF35)，它可以稳定地 在CLL质膜上高水平表达。本项目有以下具体目标：(1) 继续分析白血病细胞数量急剧下降的机制(S) 在自体Ad-CD154-转导或ISF35-转导的CLL细胞治疗的患者中观察；(2) 检测针对新发现的CLL相关抗原Ror1的细胞免疫反应；(3)评估 Ad-CD154基因治疗诱导的抗白血病抗体的特异性和生物学活性 特别强调抗Rorl自身抗体。(4)开发项目中生成的E-MU-TCL1小鼠模型 1评估旨在最大化Ad-CD154基因治疗活性的参数，无论是单独还是在 结合抗白血病药物或以免疫为基础的治疗策略。

Patients treated with autologous CLL cells transduced with an adenovirus encoding murine CD154 (Ad- CD154) experienced acute declines in leukemia cell counts and lymph node size and long-term desirable effects, including increased numbers of leukemia-reactive T cells, generation of anti-CLL antibodies, and apparent slowing or halting of disease progression. Treated patients had changes in bystander nontransfected CLL cells, reflecting activation by CD154 in vivo. We found that CD154-activation induced a programmed series of events in CLL cells, which initially were transiently protected and then sensitized to apoptosis induced by ligation of induced extrinsic death receptors (e.g. CD95 and DR5), cytotoxic drugs, or novel agents that inhibit the inhibitor of apoptosis (IAP) proteins (see project 2). Sensitivity to these agents appears associated with the capacity of CD154-activation to induce expression of the pro-apoptotic molecule Bid through a p53-independent, c-Abl-dependent mechanism, which apparently involves the alpha isoform of p73. This raises the exciting prospect that Ad-CD154 gene therapy may circumvent the dependency on p53 of anti-leukemia drugs, while inducing anti-leukemia cellular and antibody immune responses. The latter already have allowed us to identify a novel CLL-associated antigen, Ror1, which potentially could be used in assays to monitor the activity of Ad-CD154 gene therapy or in vaccines for immune therapy of this disease. For future clinical studies, we developed a "humanized" CD154 (designated ISF35) that can be stably expressed at high-levels on the CLL plasma membrane. This project has the following specific aims: (1) Continue ongoing analyses of the mechanism(s) responsible for the acute fall in leukemia-cell counts observed in patients treated with autologous Ad-CD154-transduced, or ISF35-transduced, CLL cells; (2) Examine cellular immune responses against a newly-identified CLL-associated antigen, Ror1; (3) Evaluate the specificity and biologic activity of anti-leukemia antibodies induced by Ad-CD154 gene therapy, with special emphasis on anti-Rorl autoantibodies. (4) Develop the E mu-TCL1 mouse model generated in Project 1 to evaluate parameters intended to maximize the activity of Ad-CD154 gene therapy, either alone or in combination with anti-leukemia drugs or immune-based treatment strategies.