IMMUNOTHERAPY OF PSORIASIS--MECHANISM OF DAB 389

寻常型银屑病是一种人类炎症性皮肤病，其特征是 组织内可见IL-2R+淋巴细胞和明显的表皮改变。 我们认为银屑病是一种主要由免疫调节的疾病，如 临床和病理疾病特征可通过治疗逆转 DAB389IL-2，一种只与细胞反应的新型融合毒素 表达高亲和力的IL-2R。我们的主要假设是牛皮癣 一种由表皮反应引起的自身免疫性疾病 角质形成细胞至IL-2R+组织浸润性白细胞，极有可能 CD8+CD25+TIA-1+细胞毒效应分子，我们已经在 大量出现在病变的表皮中。这项建议的具体目的 包括： 1.建立DAB389IL-2特异性杀伤T淋巴细胞的能力 从病变组织中携带IL-2受体并相关的变化 组织浸润性白细胞的定量和定性检测 银屑病病理的其他细胞特征的改变。 2.确定激活和功能状态的变化 DAB389IL-2治疗期间的皮肤白细胞。 3.测定DAB-IL-2治疗对小鼠的数量和功能的影响 可以从皮肤活检组织中克隆的IL-2反应性T细胞。 使用一系列有效的标志物来量化临床的程度 疾病，我们建议将治疗的改善与数字联系起来， 银屑病患者特异性白细胞亚群的功能及激活状态 组织。我们将使用敏感的免疫组织化学方法 冷冻机准备的组织切片，我们将评估功能 通过一种新技术激活与疾病相关的白细胞 使我们能够从牛皮癣组织中恢复存活的白细胞。我们会 确定DAB389IL-2是否耗尽效应CD8+淋巴细胞 银屑病组织，和/或该制剂是否作用于抗原提呈 树突状细胞或CD4+淋巴细胞。DAB389IL-2可能 改变炎性细胞因子和免疫调节细胞因子的产生 将通过克隆和分析疾病相关的T- 用有限稀释法检测治疗前后淋巴细胞的变化。 将银屑病作为一种模型自身免疫性疾病的研究是有利的 因为(1)牛皮癣是人类最常见的自身免疫性疾病， 影响2-3%的人口，(2)牛皮癣的疾病活动性 庸俗相对稳定，允许研究的相对较少 建立患者群体预后的意义，(3)临床 疾病活动是可见的，并可以通过有效的测量进行量化 和非侵入性成像，(4)病变和非病变组织容易 可用于对比实验室研究，(5)靶向上皮细胞 可以很容易地在体外培养以检测与效应器的相互作用 白细胞或免疫衍生细胞因子，以及(6)浓缩的，功能性的 组织浸润性白细胞群体可以直接获得 通过一种新的器官培养系统进行研究。

Psoriasis vulgaris is a human inflammatory skin disorder characterized by tissue infiltration with IL-2R+ lymphocytes and marked epidermal changes. We propose that psoriasis is a primary immune-mediated disorder, as clinical and pathological disease features can be reversed by treatment with DAB389IL-2, a novel fusion toxin which reacts only with cells expressing high affinity IL-2R. Our major hypothesis is that psoriasis is an autoimmune disease that is caused by a response of epidermal keratinocytes to lL-2R+ tissue infiltrating leukocytes, most probably CD8+CD25+TIA-1+ cytotoxic effectors, cells that we have identified in large numbers in diseased epidermis. The specific aims of this proposal are: 1. To establish the specific ability of DAB389IL-2 to delete T-lymphocytes bearing lL-2 receptors from diseased tissue and to correlate changes in tissue-infiltrating leukocytes with quantitative and qualitative alterations in other cellular features of psoriatic pathology. 2. To determine changes in the activational and functional state of cutaneous leukocytes during treatment with DAB389IL-2. 3. To determine the effect of DAB-lL-2 therapy on the number and function of lL-2 reactive T cells that can be cloned from skin biopsies. Using a series of validated markers to quantify the extent of clinical disease, we propose to relate therapeutic improvements to number, function, and activation state of specific leukocyte subsets in psoriatic tissue. We will employ sensitive immunohistochemical approaches on cryostat-prepared tissue sections, and we will assess functional activation of disease-related leukocytes through a new technique that allows us to recover viable leukocytes from psoriatic tissues. We will establish whether DAB389IL-2 depletes effector CD8+ lymphocytes from psoriatic tissues, and/or whether this agent acts on antigen presenting dendritic cells or CD4+ lymphocytes. The possibility that DAB389IL-2 alters production of inflammatory cytokines and immunoregulatory cytokines will be explored by cloning and analysis of disease-associated T- lymphocytes before and after therapy by limiting dilution approaches. The study of psoriasis as a model autoimmune disease is advantageous because (1) psoriasis is the most common human autoimmune disorder, affecting 2-3% of the population, (2) disease activity in psoriasis vulgaris is relatively stable, allowing for study of relatively small patient populations to establish significance of outcomes, (3) clinical disease activity is visible and can be quantified by validated measures and non-invasive imaging, (4) lesional and non-lesional tissue is readily available for comparative laboratory studies, (5) target epithelial cells can be readily cultured in vitro to examine interactions with effector leukocytes or immune-derived cytokines, and (6) enriched, functional populations of tissue-infiltrating leukocytes can be obtained for direct study by a novel organ culture system.