(CRCL) vaccine for Chronic Myelogenous Leukemia

描述(申请人提供)：我们的实验室已经开发出一种全新的方法来生产抗癌疫苗。利用自由溶液等电聚焦(FS-IEF)技术，我们可以有效地从肿瘤裂解物中富集多个伴侣复合体。已有文献证明，用这些富含伴侣的细胞裂解物(CRCL)免疫比用纯化的单个伴侣(热休克蛋白，HSP)免疫更有效。CRCL的抗原性可以通过将其装载到树突状细胞(DC)上而进一步增强，从而即使在先前存在疾病的情况下也能保护小鼠免受肿瘤的侵袭。除了携带抗原的能力外，CRCL对DC也有很强的免疫刺激作用。作为佐剂，CRCL提供了危险信号，增强了药物治疗后白血病细胞凋亡的免疫原性。慢性粒细胞白血病(CML)是研究CRCL伴随多肽的抗原特异性免疫反应的有效模型。它在白血病中是独一无二的，因为bcr-abl癌基因本身就是一种肿瘤抗原。此外，CML细胞还表达其他潜在的靶抗原，如蛋白水解酶-3和Wilms肿瘤蛋白(WT1)。这项提议的目标是产生足够强大的临床前数据，将CRCL疫苗推向临床环境。为进一步了解CRCL疫苗的作用机制，本实验室拟继续对12B1小鼠CML模型进行研究。同时，体外研究将检查人类慢性粒细胞白血病来源的CRCL对人类细胞的影响，以确定其有效性和安全性。提出了以下具体目标。1)鉴定12B1小鼠白血病CRCL疫苗多肽抗原库。2)研究CRCL疫苗/佐剂联合酪氨酸激酶抑制剂STI-571对小鼠12B1 bcr-abl+细胞的体内协同作用。3)人慢性粒细胞白血病来源的慢性粒细胞白血病的生化特性。4)评价人慢性粒细胞白血病来源的CRCL对人DC的作用，并检测CRCL致敏的DC产生白血病特异性CTL的能力。这些目标的成功实现可能导致CRCL作为一种有效的疫苗用于治疗慢性粒细胞白血病，这种疾病的免疫治疗已经显示出希望。

DESCRIPTION (provided by applicant): Our laboratory has developed a completely new approach to generating an anticancer vaccine. Using a free solution isoelectric focusing (FS-IEF) technique we can efficiently enrich for multiple chaperone complexes from tumor lysates. It has been documented that vaccination with these chaperone rich cell lysates (CRCL) is more effective than immunization with purified individual chaperones (heat shock proteins, HSPs). The antigenicity of CRCL can be augmented further by loading them onto dendritic cells (DCs) resulting in protection against murine tumors even in the setting of pre-existing disease. In addition to their antigen carrying capacities, CRCL have potent immunostimulatory effects on DCs. As adjuvants CRCL provide danger signals enhancing the immunogenicity of leukemia cells undergoing apoptosis following drug treatment. Chronic Myelogenous Leukemia (CML) is a useful model for the study of antigen specific immune responses to peptides chaperoned by CRCL. It is unique among leukemias in that the bcr-abl oncogene itself is a tumor antigen. Moreover, CML cells express other potential target antigens such as Proteinase-3 and Wilms' tumor protein (WT1). The goal of this proposal is to generate sufficiently strong pre-clinical data to move CRCL vaccines into the clinical setting. Our laboratory intends to continue studies in the 12B1 murine CML model in order to understand further the mechanisms of action of CRCL vaccines. In parallel, in vitro studies will examine the effects of human CML-derived CRCL on human cells in order to establish efficacy and safety. The following specific aims are proposed. 1) Characterize the peptide antigen repertoire of CRCL vaccine derived from 12B1 murine leukemia. 2) Study the in vivo synergistic effects of combining CRCL vaccine/adjuvant with STI-571, a tyrosine kinase inhibitor that induces apoptosis in murine 12B1 bcr-abl+ cells. 3) Biochemically characterize human CML-derived CRCL. 4) Evaluate the effects of human CML-derived CRCL on human DCs and examine the potential of CRCL-pulsed DCs to generate leukemia specific CTLs. The successful completion of these aims may result in the use of CRCL as an effective vaccine against CML, a disease in which immunotherapy has already shown promise.