T CELL UNRESPONSIVENESS IN HUMAN TUMORS

确定宿主对人类肿瘤的免疫反应的研究集中在 这部分取决于肿瘤床内T细胞的特征。 图片 在功能反应方面是复杂的 这些细胞。 肿瘤浸润淋巴细胞（TIL）含有反应性T细胞， 显示正常效应子功能的细胞。 同样清楚的是， 来自多种肿瘤的TIL的显著部分在它们的免疫应答中是有缺陷的。 增殖反应 我们已经证明TIL来源于人类， RCC和B细胞淋巴瘤的增殖反应降低， 反映在IL 2 R α表面表达和mRNA表达的减少， 程度. 虽然TIL可以产生相当水平的IFN γ， 与PBL相比，它们还显示出产生IL 2的能力降低。 我们 一种假设是，虽然一部分TIL是有反应， 显示出范围相当有限的无反应状态。 其他 功能参数被认为是完整的，即使大多数TIL具有 增殖和产生IL 2的能力减弱。 目标1将决定 TIL的哪些亚群受影响最大。 细胞分选实验“将 确定增殖缺陷是否在T细胞中不均匀分布， 亚群（CD 4+和CD 8+细胞），如果缺陷与 肿瘤床中T细胞的活化。 目标2将确定 通过确定其他功能参数是否 在受影响的人群中完好无损。 纯化的TIL亚群将用于 记录TIL是否在其产生IL 2的能力方面存在缺陷。 缺陷是否限于IL 2将通过测试TIL来确定， 其他细胞因子如IL 4、TNF α和GM-CSF的产生。 实验还将确定TIL是否与PBL一样有能力产生 穿孔素和丝氨酸酯酶的mRNA。 额外的工作将定义 各种刺激途径在无反应性中的作用。 分析 IL-2 R和TCR刺激诱导的多种功能将有助于确定 这些受体受影响的程度。 实验将 还确定通过CD 28触发TIL是否正常，因为该途径 似乎与TCR诱导的不同。 目标3将确定是否 TIL的IL 2 R α表面表达和IL 2产生减少， 与转录的改变有关。 RT/PCR将用于定量 TIL和PBL的mRNA水平。 包括将研究，以确定是否 mRNA水平的降低是由于mRNA表达动力学的改变， 积累、转录速率或mRNA稳定性。 的目标 建议的工作是开始了解缺陷的范围， 确定受影响的子集以及哪些受体途径 在无反应的TIL中改变。 重要的是， 定量和定性的T细胞无反应性， 肿瘤 对这种无反应性的理解可能会提供逆转或 绕过这一缺陷，允许T细胞活化和细胞的发育 宿主对肿瘤的免疫反应。 了解T细胞无反应性 疾病状态，如癌症，将是重要的发展， 治疗策略。

Studies to define the host immune response to human tumor has concentrated in part on characterizing the T cells within the tumor bed. The picture that has immerged is complex with respect to the functional responsiveness of these cells. Tumor infiltrating lymphocytes (TIL) contain responsive T cells that display normal effector functions. It is also clear that a significant portion of TIL from a variety of tumors are defective in their proliferative response. We have demonstrated that TIL derived from human RCC and B cell lymphomas have a reduced proliferative response that is reflected by a decrease in the IL2Ralpha surface expression and mRNA levels. While TIL can produce comparable levels of IFNgamma when compared to PBL they also display a diminished capacity to produce IL2. Our hypothesis is that while a segment of TIL are responsive the majority display a state of unresponsiveness that is rather limited in scope. Other functional parameters are thought to be intact even though most TIL have a diminished ability to proliferate and produce IL2. Aim 1 will determine which subsets of TIL are most affected. Cell sorting experiments "will determine if the proliferative defect is unequally distributed among T cell subsets (CD4+ and CD8+ cells) and if the defect relates to the state of activation of T cells in the tumor bed. Aim 2 will define the extent of the unresponsiveness by determining if other functional parameters are intact in the affected populations. Purified TIL subsets will be used to document whether TIL are defective in their ability to produce IL2. Whether the defect is limited to IL2 will he determined by testing TIL for the production of other cytokines such as IL4, TNFalpha and GM-CSF. Experiments will also determine if TIL are as competent as PBL to produce mRNA for perforin and serine esterases. Additional work will define the role various stimulation routes play in the unresponsiveness. An analysis of multiple functions induced by IL2R and TCR stimulation will help define the extent to which each of these receptors are affected. Experiments will also determine if triggering TIL via CD28 is normal since this pathway appears to be distinct from that induced by TCR. Aim 3 will determine if the reduced IL2Ralpha surface expression and IL2 production of TIL is related to alterations in transcription. RT/PCR will be used to quantitate mRNA levels of TIL and PBL. Included will be studies that determine if the reduction in mRNA levels is due to changes in the kinetics of mRNA accumulation, rate of transcription or mRNA stability. The goal of the proposed work is to begin to understand how broad the defect is, and to identify the subsets affected as well as which receptor pathways are altered in the unresponsive TIL. It is important to characterize quantitatively and qualitatively the T cell unresponsiveness within the tumor. An understanding of this anergy may provide ways to reverse or bypass this defect allowing for T cell activation and the development of a potent host immune response to tumors. Understanding T cell anergy in disease states such as cancer will be important for the development of new treatment strategies.