MECHANISMS OF LYMPHOCYTE MEDIATED AIRWAY HYPERREACTIVITY

哮喘在美国影响着数以百万计的人，它 发病率和死亡率都在增加。尽管有证据支持一个角色 对于T细胞介导的气道炎症在其发病机制中的确切作用 淋巴细胞发挥作用还不是很清楚。首席调查员(P.I.) 已经开发出一种哮喘小鼠模型，在这种模型中，致敏和挑战 小鼠发展到晚期，呼吸道阻力增加近100倍 增加呼吸道高反应性(AHR)，这可以通过 通过一种新的淋巴细胞种群转移到幼鼠身上 CD3的表面表达，但表达Thy 1和Thy 1的表面决定簇 CD45RA。P&gT；I&gT；假设：(1)AHR与炎症 哮喘的特征是由这部小说《Thy 1》引发的 +CD45RA+淋巴细胞群；(2)这些细胞诱导哮喘 通过产生细胞因子或招募和/或激活他人来提高素质 呼吸道效应细胞：以及(3)这些细胞启动哮喘 素质，部分是通过改变肺内皮细胞的表型 和/或平滑肌细胞。具体目标是： 一、表征CD3-。Thy 1+和CD45 RA+转移性淋巴细胞 人口(S)。私家侦探将：(A)确定收养转移是否 由同时表达Thy-1和Thy-1的单个CD3细胞群介导 CD45A：，(B)分离、永生化和鉴定稳定克隆(S) (C)表征CD45异构体表面 克隆的转移性淋巴细胞群的表达；(D)测定 CD-3转移性淋巴细胞抗原特异性的机制 人口。(E)确定该淋巴细胞的细胞因子特征 人口。将特别注意确定它是否 产生细胞因子，使T细胞分化为Th2表型。 II.描述渗入呼吸道的白细胞的特征 这些动物。将使用免疫组织化学和原位杂交技术 大鼠呼吸道细胞的免疫分型及细胞因子谱特征 这些动物。 III.描述调节呼吸道的效应细胞群 此模型中的效果。私家侦探将分析领养的影响 转移到免疫缺陷小鼠品系和受体正常小鼠 在体内耗尽某些潜在的效应细胞群之后。 建立体外共培养模型，以评估这些因素的影响 转移淋巴细胞对血管内皮细胞的激活和平滑 肌肉。 对这一独特模型的分析总结了许多小鼠的 人类哮喘的特征将使我们能够准确地定义淋巴细胞 人群(S)负责诱发哮喘的素质和 开始描述它们调节其影响的机制。

Asthma affects millions of individuals in the United States, and its morbidity and mortality are increasing. Although evidence supports a role for T-cell mediated airway inflammation in its pathogenesis, the exact role that lymphocytes play is not understood. The Principle Investigator (P.I.) has developed a murine model of asthma in which sensitized and challenged mice develop late phase increases in airways resistance and nearly 100 fold increases in airway hyperreactivity (AHR), which can be adoptively transferred to naive mice by a novel population of lymphocytes that lack surface expression of CD3, but express surface determinants for Thy 1 and CD45RA. The P>I> hypothesizes that; (1) AHR and inflammation characteristic of asthma is initiated by this novel Thy 1 +CD45RA+lymphocyte population; (2) that these cells induce the asthmatic diathesis by producing cytokines or recruiting and/or activating other airway effector cells: and (3) that these cells initiate the asthmatic diathesis, in part by altering the phenotype of lung endothelial cells and/or smooth muscle cells. The specific aims are to; I. Characterize the CD3-. Thy 1+ and CD45 RA+ transferring lymphocyte population(s). The P.I. will: (A) Determine if adoptive transfer is mediated by a single population of CD3- cells expressing both Thy 1 and CD45A:, (B) Isolate, immortalize an characterize a stable clone(s) that mediates this adoptive transfer; (C) Characterize the CD45 isoform surface expression of the cloned transferring lymphocyte population; (D) Determine the mechanism of antigen specificity of this CD-3 transferring lymphocyte population. (E) Characterize the cytokine profile of this lymphocyte population. Particular attention will be devoted to determining if it produces cytokines which differentiate T cells to Th2 phenotype. II. Characterize the leukocyte populations infiltrating the airways of these animals. Immunohistochemistry and in situ hybridization will be used to immunotype and characterize the cytokine profile of the airway cells in these animals. III. Characterize the effector cell populations that mediate the airways effects in this model. The P.I. will analyze the effect of adoptive transfer to immunodeficient mouse strains and to recipient normal mice after in vivo depletion of certain potential effector cell populations. IV. Establish in vitro co-culture models to evaluate the effects of these transferring lymphocytes on the activation of endothelium and smooth muscle. Analysis of this unique model which recapitulates in mice many of the features of human asthma will allow us to precisely define the lymphocyte population(s) responsible for the induction of the asthmatic diathesis and begin to characterize the mechanisms by which they mediate their effects.