Immunologic targets in Myeloid Leukemia

描述（由申请人提供）：现在有明确的证据表明，免疫系统能够检测和反应由经历肿瘤转化的正常细胞产生的细胞应激信号以及由此产生的癌症。虽然这种反应的频率和幅度在个体之间变化很大，但临床前模型和临床研究都已经确定，癌症表型、其生物学行为和临床预后受到宿主免疫反应特征的深刻影响。细胞和体液免疫识别癌细胞上的广泛抗原靶标，其中许多被用作免疫疗法的候选物。然而，癌症是由异质细胞群组成的，基因表达模式和靶抗原的分布各不相同。这些表型差异叠加在癌细胞亚群自我更新和传播恶性肿瘤的能力的功能差异上。因此，几乎没有证据来指导这些抗原中的哪一种在靶向时最有可能赋予临床益处。我们试图在两种临床环境中使用无偏倚的抗原鉴定策略来解决这一局限性，其中存在免疫介导的临床效应的可测量证据;在1）慢性髓性白血病（CML）和2）急性髓性白血病（AML）的疫苗相关缓解诱导中。将根据以下标准对这些筛选中鉴定的抗原进行优先排序：1）免疫识别与临床应答的相关性，2）白血病干细胞（LSC）的表达，3）抗体和T细胞应答的检测，以及4）基因在白血病发生途径中发挥的生物学作用。将基于其靶向对白血病与正常造血的体内植入的影响来验证优先化抗原。这些发现将为癌症干细胞的基本成分提供重要的见解，有助于建立预测临床反应的免疫实验室相关性，并指导确定抗原疫苗或过继性T细胞治疗白血病的抗原靶点的选择。

DESCRIPTION (provided by applicant): There is now unequivocal evidence that the immune system is equipped to detect and react to cellular stress signals generated by normal cells undergoing neoplastic transformation and the cancers that arise from them. Although the frequency and magnitude of such responses vary considerably between individuals, both pre-clinical models and clinical studies have established that the cancer phenotype, its biological behavior, and clinical prognosis are profoundly influenced by the character of the host immune response. Cellular and humoral immunity recognize a wide range of antigenic targets on cancer cells, many of which are being pursued as candidates for immunotherapy. Yet cancers are comprised of heterogeneous cell populations, varying in patterns of gene expression and in the resulting distribution of target antigens. These phenotypic differences are superimposed upon functional differences in the capacity of subsets of cancer cells to self-renew and propagate the malignancy. Consequently, there is little evidence to guide which of these antigens when targeted are most likely to confer clinical benefit. We seek to address this limitation using an unbiased antigen identification strategy in two clinical settings where there is measurable evidence of an immune mediated clinical effect; in vaccine associated remission induction in 1) chronic myelogenous leukemia (CML) and 2) acute myelogenous leukemia (AML). Antigens identified in these screenings will be prioritized based on the following criteria: 1) correlation of immune recognition with clinical response, 2) expression by leukemic stem cells (LSCs), 3) detection of both antibody and T cell responses, and 4) the biological role played by the gene in pathways of leukemogenesis. Prioritized antigens will be validated based on the impact of their targeting on in vivo engraftment of leukemia versus normal hematopoiesis. These findings will provide significant insight into the essential components of cancer stem cells, help to establish immune laboratory correlates predictive of clinical responses, and guide the selection of antigenic targets for defined-antigen vaccine or adoptive T cell therapies for leukemia.