T CELL UNRESPONSIVENESS IN HUMAN TUMORS

关于确定宿主对人类肿瘤的免疫反应的研究已经集中 在一定程度上取决于肿瘤床内T细胞的特征。这张照片 就功能反应性而言，已经被浸没的是复杂的 这些细胞。肿瘤浸润性淋巴细胞(TIL)含有反应性T细胞 显示正常效应器功能的细胞。同样明显的是，一个 来自各种肿瘤的TIL的很大一部分是有缺陷的 增殖反应。我们已经证明了TIL来源于人类 肾细胞癌和B细胞淋巴瘤的增殖反应减弱，即 反映为IL2Rpha表面表达和mRNA的减少 级别。而与TIL相比，TIL可以产生类似水平的IFNGamma 对于PBL，它们也表现出生产IL2的能力减弱。我们的 假设是，虽然TIL的一部分对大多数有反应 显示一种在范围上相当有限的无响应状态。其他 函数参数被认为是完整的，即使大多数TIL具有 增殖和产生白介素2的能力减弱。目标一号将决定 TIL的哪些子集受影响最大。细胞分选实验“将 确定增殖性缺陷在T细胞中的分布是否不均匀 亚群(CD4+和CD8+细胞)以及缺陷是否与 激活肿瘤床中的T细胞。目标2将定义 通过确定其他功能参数是否 在受影响的人群中完好无损。提纯的TIL亚集将用于 记录TIL生产IL2的能力是否有缺陷。 缺陷是否仅限于IL2将通过测试TIL来确定 其他细胞因子的产生，如IL4、TNFpha和GM-CSF。 实验还将确定TIL是否与PBL一样有能力生产 穿孔素和丝氨酸酯酶的mRNA。其他工作将定义 不同的刺激途径在无反应中起作用。一项分析 IL2R和TCR刺激所诱导的多种功能将有助于确定 这些受体中每一个都受到影响的程度。实验将会 还要确定通过CD28触发TIL是否正常，因为此途径 似乎与TCR诱导的不同。目标3将决定是否 TIL表面IL2Rα表达减少，IL2产生减少 与转录变化有关的。RT/PCR将用于定量检测 TIL和PBL的mRNA水平。将包括一些研究，以确定是否 信使核糖核酸水平的降低是由于信使核糖核酸动力学的改变 积累量、转录速率或mRNA的稳定性。的目标是 建议的工作是开始了解缺陷有多广泛，并 确定受影响的子集以及哪些受体途径 在无反应的TIL中更改。重要的是要刻画出 T细胞在数量和质量上的无反应 肿瘤。对这种无能的理解可能会提供逆转或 绕过这一缺陷，允许T细胞激活和发展成 强大的宿主对肿瘤的免疫反应。对T细胞无能的认识 癌症等疾病状态将对新的 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.