IMMUNOPATHOGENESIS OF LYMPHATIC FILARIASIS

在拟议的研究中，我们将研究免疫机制， 局部接触丝虫抗原激活的T淋巴细胞， 负责启动局部淋巴损伤， 在感染吴策线虫的个体中观察到的病理表现 bancrofti。 受体对丝虫免疫病理学的贡献 在活化的T细胞表面和由 在内皮细胞表面上局部产生的细胞因子将被 评估。 由于没有班氏丝虫病的动物模型， 将对流行地区的受感染者进行研究。 通过比较和 感染个体与寄生虫诱导的淋巴病理的对比 到完全无症状但同样严重感染的微丝蚴病 个体，特异性免疫粘附受体的作用， 整合素和免疫球蛋白超家族介导的破坏性 W.将调查班氏感染。 具体的实验目的是：1）将受感染的个体分为2个阶段 用于体外免疫学测定的临床组， 炎症性浅表淋巴管的免疫组织学染色 免疫学结果的体内相关性; 2）通过细胞定量 ELISA检测患者PBMC培养上清中细胞因子的能力 诱导内皮细胞表面MHC分子和粘附受体的表达， 在体外模型系统中的细胞。 特定细胞因子的水平将是 与受体表达相关。 受体阻断剂的作用将 3）在体外粘附试验中，检查 患者T细胞上的受体介导对培养的内皮细胞的粘附 已经用重组细胞因子人工刺激的细胞， 诱导已知粘附受体最大表达;和4）检测 T细胞粘附于已通过预测定激活的内皮细胞 与患者细胞衍生的细胞因子上清液孵育，利用 内皮细胞和T细胞受体的最佳实验条件 具体目标2和3中分别定义的表达。 将检查mAb阻断细胞表面受体的作用。 粘附受体和配体，是潜在的目标， 用单克隆抗体、可溶性受体 类似物，或封闭肽将被确定，打开一个可能的新的 疾病控制的方法。 最重要的是， 体外模型系统将导致筛选定义的能力， 重组丝虫抗原，当它们变得可用时， 免疫致病潜力，导致抗- 病理学候选疫苗

In the proposed study we will examine the immunologic mechanisms by which T-lymphocytes activated by local contact with filarial antigen are responsible for initiating the local lymphatic damage that is the central pathological manifestation seen in individuals infected with Wuchereria bancrofti. The contributions to filarial immunopathology of receptors expressed on the surface of activated T-cells and of receptors induced by locally produced cytokines on the surface of endothelial cells will be assessed. Because there is no animal model of bancroftian filariasis, infected humans in an endemic area will be studied. By comparing and contrasting infected individuals with parasite induced lymphatic pathology to completely asymptomatic but equally heavily infected microfilaremic individuals, the role of specific immunologic adhesion receptors of the integrin and immunoglobulin superfamilies in mediating the destructive lymphatic pathology seen in W. bancrofti infections will be investigated. The specific experimental aims are: 1) to stage infected individuals into 2 clinical groups for in vitro immunological assays and to perform immunohistologic staining of inflamed superficial lymphatic vessels for in vivo correlation of the immunological findings; 2) to quantitate by a cell ELISA the ability of cytokines in patient derived PBMC culture supernatants to induce expression of MHC molecules and adhesion receptors on endothelial cells in an in vitro model system. Levels of specific cytokines will be correlated with receptor expression. The effect of receptor blockade will be assessed; 3) to examine, in an in vitro adhesion assay, the role of receptors on patient T-cells in mediating adherence to cultured endothelial cells that have been artificially stimulated with recombinant cytokines to induce maximal expression of known adhesion receptors; and 4) to examine T-cell adhesion to endothelial cells which have been activated by preassay incubation with patient cell derived cytokine supernatants, utilizing optimal experimental conditions for endothelial cell and T-cell receptor expression that had been defined separately in Specific Aims 2 and 3. Effects of mAb blockade of cell surface receptors will be examined. Adhesion receptors and ligands that are potential targets for immuno-therapeutic blockade with monoclonal antibodies, soluble receptor analogues, or blocking peptides will be identified, opening a possible new approach to disease control. Most importantly, further refinement of the in vitro model system will lead to the ability to screen defined recombinant filarial antigens, when they become available, for their immunopathogenic potential, leading to the identification of anti- pathology vaccine candidates.