LEUKOCYTE-ENDOTHELIAL CELL ADHESION IN TUMOR IMMUNITY

肿瘤免疫中的白细胞-内皮细胞粘附

• 批准号: 6475826
• 负责人: Sharon S Evans
• 金额: $ 20.75万
• 依托单位: ROSWELL PARK CANCER INSTITUTE CORP
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-12-13 至 2003-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6475826
• 关键词: T cell receptor; antineoplastics; biological signal transduction; cell adhesion; cytotoxic T lymphocyte; disease /disorder model; genetically modified animals; hyperthermia therapy; immunocytochemistry; integrins; interleukin 6; laboratory mouse; leukocytes; lymph nodes; monoclonal antibody; natural killer cells; neoplasm /cancer immunology; neoplastic cell; neoplastic process; pancreatic islet neoplasm; protein structure function; receptor expression; selectins; tissue /cell culture; vascular endothelium

This proposal addresses the central hypothesis that significant antitumor responses can be achieved through the use of fever- range hyperthermia to stimulate L-selectin and alpha4beta7 integrin-dependent recruitment of immune effector cells to malignant tissues and tumor-draining lymph nodes. The hypothesis is formulated on the basis of new information demonstrating that fever range, long duration whole body hyperthermia (WBH) stimulates expression of endothelial ligands for two leukocyte homing receptors, L-selectin and alpha4beta7 integrin, on tumor vessels in the RIP-Tag5 transgenic mouse model. This finding is correlated with increased lymphocyte infiltration into beta islet tumors. Notably, pancreatic tumors that develop as a result of transgene expression of the SV40 T antigen (Tag) in RIP-Tag5 mice are normally devoid of infiltrating lymphocytes. Three independent approaches are proposed to address the central hypothesis: (1) Strategies are designed to examine the direct role of L-selectin and alpha4beta7 integrin in targeting immune effector cells to pancreatic beta islet tumors in response to fever-range WBH in RIP-Tag5 single transgenic mice and in RIP- Tag5 double transgenic mice that have a high frequency of tumor- reactive cytotoxic T lymphocytes (CTL) as a result of coexpression of the B7.1 costimulatory molecule or a Tag-specific T cell receptor. The specific role of adhesion molecules in lymphocyte recruitment will be delineated by antibody blockade studies and using cell lines that restrictively bind to endothelium via L-selectin or alpha4beta7 integrin. (2) The molecular mechanisms underlying hyperthermia control of lymphocyte-endothelial adhesion will be investigated in cell lines using in vitro kinase assays and dominant negative approaches to examine the involvement of specific signal transduction pathways (i.e., MAPK, HSP90, JAK/STATs, Src kinases, and IL-6). (3) Studies are designed to determine if fever-range WBH, in combination with cytokines (IFN-alpha, IL-2), inhibits tumor progression in RIP-Tag transgenic mice by enhancing L- selectin and/or alpha4beta7 integrin-dependent accumulation of CTL in beta islet tumors. WBH effects on intratumoral localization of immune cells that produce Th1-cytokines (e.g., IFN-gamma) will also be examined since these cytokines are fundamental to the generation of cell-mediated tumor immunity. The proposed studies are expected to provide a framework for future evaluation of the efficacy of fever-range WBH as an adjuvant in the treatment of cancer in combination with immunotherapies designed to enhance the generation of tumor- specific CTL.

本研究提出了一个中心假设，即通过使用发热范围内的高温来刺激l -选择素和alpha4beta7整合素依赖的免疫效应细胞向恶性组织和肿瘤引流淋巴结募集，可以实现显著的抗肿瘤反应。这一假设是基于新的信息提出的，这些信息表明，在ip - tag5转基因小鼠模型中，发烧范围、长时间全身高温（WBH）可以刺激肿瘤血管上两种白细胞归巢受体（l -选择素和alpha4beta7整合素）的内皮配体表达。这一发现与胰岛肿瘤淋巴细胞浸润增加有关。值得注意的是，在RIP-Tag5小鼠中，由于SV40 T抗原（Tag）的转基因表达而产生的胰腺肿瘤通常没有浸润淋巴细胞。提出了三种独立的方法来解决中心假设：(1)在RIP-Tag5单转基因小鼠和RIP-Tag5双转基因小鼠中，由于B7.1共刺激分子或标签特异性T细胞受体的共同表达，具有高频率的肿瘤反应性细胞毒性T淋巴细胞（CTL），设计策略以检测l -选择素和alpha4beta7整合素在针对胰岛肿瘤的免疫效应细胞靶向中的直接作用。粘附分子在淋巴细胞募集中的具体作用将通过抗体阻断研究和使用通过l -选择素或alpha4beta7整合素限制性结合内皮的细胞系来描述。(2)高温控制淋巴细胞内皮粘附的分子机制将在细胞系中进行研究，使用体外激酶测定和显性阴性方法来检查特定信号转导途径（即MAPK， HSP90, JAK/STATs， Src激酶和IL-6）的参与。(3)研究旨在确定发热范围的WBH是否与细胞因子（ifn - α, IL-2）联合，通过增强胰岛肿瘤中L-选择素和/或alpha4beta7整合素依赖的CTL积累，抑制了riptag转基因小鼠的肿瘤进展。WBH对产生th1 -细胞因子（如ifn - γ）的免疫细胞瘤内定位的影响也将被研究，因为这些细胞因子是产生细胞介导的肿瘤免疫的基础。拟议的研究预计将为未来评估发热范围WBH作为辅助治疗癌症的疗效提供一个框架，该辅助治疗与旨在增强肿瘤特异性CTL生成的免疫疗法联合使用。