Genetic Targeting of T cells to B cell malignancies

描述（由申请人提供）： CD 19在大多数恶性B细胞和正常B细胞上选择性表达，但在血液干细胞上不表达，因此是癌症免疫治疗的有吸引力的靶标。 已经开发了编码与TCR ζ链融合的CD 19特异性单链片段（scFv）抗体的逆转录病毒载体。 经转导以表达该人工T细胞受体（称为19 z1）的T细胞在体外特异性裂解表达人CD 19（hCD 19）的肿瘤细胞系。 此外，与用不相关的人工T细胞受体（Pz 1）转导的T细胞处理的小鼠相比，用19 z1修饰的人T细胞处理携带已建立的系统性hCD 19 + Raji肿瘤细胞的SCID-米色小鼠导致肿瘤进展时间和总存活率以剂量依赖性方式增加。 然而，对这些数据的解释受到T细胞和肿瘤细胞对SCID-米色小鼠的异种性质以及宿主免疫受损状态的限制。 因此，该提议的总体目标是使用同基因免疫活性小鼠模型更好地定义19 z1转导的T细胞的活性。 为此，本提案的具体目标#1将在免疫活性hCD 19转基因小鼠中建立同源EL 4（hCD 19）肿瘤细胞的肿瘤模型，并确定19 z1+鼠T细胞是否能够根除该模型中的疾病。 为了检验T辅助细胞在过继性T细胞治疗中发挥重要作用的假设，目标#2将定义转导的CD 4 + T细胞在转导的CD 8 + T细胞的细胞毒活性、归巢和增殖中的作用。 具体目标#3将检验治愈小鼠中的次级淋巴组织和骨髓将维持转导T细胞的持久群体的假设。 将通过用EL 4（hCD 19）肿瘤细胞再激发治愈的小鼠来分析这些T细胞的功能状态。 从这些研究中获得的数据将用于合理开发B细胞恶性肿瘤人类受试者的未来临床试验。

DESCRIPTION (provided by applicant): CD19 is selectively expressed on most B cell malignancies and normal B cells but not on blood stem cells and is therefore an attractive target for cancer immunotherapy. A retroviral vector encoding a CD19 specific single chain fragment (scFv) antibody fused to a TCR zeta chain has been developed. T cells transduced to express this artificial T cell receptor (termed 19z1) specifically lyse human CD19 (hCD19) expressing tumor cell lines in vitro. Furthermore, treatment of SCID-Beige mice bearing established systemic hCD19+ Raji tumor cells with 19z1 modified human T cells results in an increased time to tumor progression and overall survival in a dose dependent manner when compared to mice treated with T cells transduced with an irrelevant artificial T cell receptor (Pz1). However, interpretation of this data is limited by the xenogeneic nature of the T cells and tumor cells to the SCID-Beige mouse, as well as the immune-compromised state of the host. Therefore, the overall objective of this proposal is to better define the activity of the 19z1 transduced T cells using a syngeneic immune competent mouse model. To this end, specific aim #1 of this proposal will establish a tumor model of syngeneic EL4(hCD19) tumor cells in an immune competent hCD19 transgenic mouse and establish whether 19z1+ murine T cells are able to eradicate disease in this model. To test the hypothesis that T helper cells play an important role in adoptive T cell therapy, aim #2 will define the role of transduced CD4+ T cells in the cytotoxic activity, homing and proliferation of transduced CD8+ T cells. Specific aim #3 will test the hypothesis that secondary lymphoid tissues and bone marrow in cured mice will maintain a persistent population of transduced T cells. The functional status of these T cells will be analyzed by rechallenge of cured mice with EL4(hCD19) tumor cells. The data derived from these studies will be applied to the rational development of future clinical trials in human subjects with B cell malignancies.