Elucidation of Pathoptysiological Roles of Immune Chemokines

免疫趋化因子病理学作用的阐明

基本信息

批准号：
11470091
负责人：
YOSHIE Osamu
金额：
$ 8万
依托单位：
Kinki University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2001
项目状态：
已结题

项目摘要

The aim of the project has been to elucidate the pathophysiological roles of the immune chemokines, which are mainly directed to lymphocytes and dendritic cells. The main accomplishments of this year are as follows. (1) We showed that the proinflammatory cytokines such as IL-1 and TNFα potently induced normal human epidermal keratinocytes to express LARC/CCL20, the chemokine known to selectively attracts immature dendritic cells and α4β7-positive memory/effector T cells vua CCR6. We also showed that the lesional skin of atopic dermatitis (AD) often contained epidermal keratinocytes producing LARC and extensive accumulation of CCR6+ cells beneath the epidermal layer. Furthermore, we showed that plasma samples from AD patients often contained elevated levels of LARC. Collectively, these results support an important pathologenic role of LARC in AD. (2) We showed that expression of LARC was potently induced in mucosal epithelial cells by proinflammatory cytokines such as IL-1 and TNFα. Fur … More thermore, we analysed the activation mechanism of the LARC promoter by these cytokines and showed that an NF-kB site from -96 to -87bp from the transcriptional initiation site was essential for the induction of the LARC promoter. (3) We showed that TARC/CCL17 and MDC/CCL22, both known to attract Th2-type memory/effector T cells and skin-seeking CLA+ memory/effector T cells via CCR4, were significantly evevated in the plasma of AD patients. Furthermore, we found that platelets contained TARC and its contents were dramatically elevated in platelets from AD patients. We further showed that IFN-γinduced normal human epidermal keratinocytes to express TARC and MDC. Collectively, TARC and MDC may play important roles in the pathogenesis of AD. Furthermore, IFN-γ, which is also known to be apotent inducer of Th1-attracting chemokines, may be a critical factor in AD pathogenesis by inducing a set of chemokines attracting both Th1 and Th2 cells. (4) We showed that a large fraction of mature dendritic cells produced MDC and were clustered with CCR4-expressing T cesss in chronically inflamed skin infected with Candida albicans as well as in lymph node. Thus, MDC may play an important role in DC-T cell interactions. (5) We showed that in an asthmatic model in mice induced by priming with and subsequent inhalating of ovalbumin, the treatment with anti-mTARC monoclonal antibody efficiently blocked lung infiltrating of lymphocytes and eosinophils and elevation of methacholine-induced airway resistance. Thus, TARC is likely to play an important role in asthma. (6) We showed that in patients with multiple sclerosis (MS), the frequencies of lymphocytes expressing CCR5 or CXCR3 was increased in the cerebrospinal fluid during exacerbation, while the frequencies of CCR5-expressinglymphocytes were decreased after remission. These results support the Th1-biased immune responses in the pathogenesis of MS. (7) We generated monoclonal antibodies to mouse chemokines such as MDC, LARC and SLC/CCL21 in Armenisan hamsters but could not get antibodies with neutralizing activities. (8) We have repeatedly backcrossed TARC-knockout mice and αE integrin-knockout mice into BALB/c and C57BL/6 mice and developed the syngeneic strains. Less

该项目的目的是阐明免疫趋化因子的病理生理作用，主要针对淋巴细胞和树突状细胞。今年的主要成就如下：（1）我们证明了促炎细胞因子，例如IL-。 1 和 TNFα 有效诱导正常人表皮角质形成细胞表达 LARC/CCL20，该趋化因子已知可选择性吸引未成熟的树突状细胞并α4β7 阳性记忆/效应 T 细胞 vua CCR6 我们还表明，特应性皮炎 (AD) 的病变皮肤通常含有产生 LARC 的表皮角蛋白细胞，并且在表皮层下大量积聚 CCR6+ 细胞。 AD 患者的 LARC 水平通常升高。总的来说，这些结果支持 LARC 在 AD 中的重要致病作用 (2) 我们表明 LARC 的表达在 AD 中被有效诱导。此外，我们分析了这些细胞因子对 LARC 启动子的激活机制，并发现从转录起始位点起 -96 至 -87bp 的 NF-kB 位点。 (3) 我们发现 TARC/CCL17 和 MDC/CCL22 都已知能吸引 Th2 型记忆/效应子。 AD患者血浆中的T细胞和通过CCR4寻找皮肤的CLA+记忆/效应T细胞显着升高。此外，我们发现AD患者的血小板中含有TARC，并且其含量显着升高。 -γ诱导正常人表皮角蛋白表达TARC和MDC，此外，TARC和MDC可能在AD的发病机制中发挥重要作用。 (4)我们发现，在感染白色念珠菌的慢性发炎皮肤以及淋巴结中，大部分成熟树突状细胞产生MDC，并与表达CCR4的T细胞聚集在一起，因此，MDC可能在DC-中发挥重要作用。 T 细胞相互作用。 (5) 我们发现，在通过启动并随后吸入卵清蛋白诱导的小鼠哮喘模型中，用抗 mTARC 单克隆抗体治疗可有效阻止淋巴细胞和嗜酸性粒细胞的肺部浸润以及醋甲胆碱诱导的气道阻力的升高。 (6) 我们发现，在多发性硬化症 (MS) 患者中，表达 CCR5 或 CXCR3 的淋巴细胞的频率较低。恶化期间脑脊液中表达 CCR5 的淋巴细胞的频率增加，而缓解后这些结果支持 MS 发病机制中的 Th1 偏向免疫反应 (7) 我们生成了针对小鼠趋化因子（如 MDC、LARC）的单克隆抗体。和亚美尼亚仓鼠中的SLC/CCL21，但无法获得具有中和活性的抗体（8）我们多次回交TARC敲除。将小鼠和 αE 整合素敲除小鼠转化为 BALB/c 和 C57BL/6 小鼠，并开发出同系品系 Less。