Study For Functional Features of The Dendritic cell

树突状细胞属于造血细胞的髓系系，是T细胞激活中最有效的免疫应答起始细胞。该项目的目的是进一步阐明树突状细胞在体内和体外与细胞发育成熟有关的功能作用。1) NLDC-145 mAb可识别在小鼠树突状细胞和胸腺上皮细胞（DEC-205）上高水平表达的205 kDa的完整膜蛋白。我们通过细胞荧光和组织学方法以及该分子的潜在功能重新检查了细胞特异性。DEC-205也可以在许多其他的白细胞亚群上检测到，特别是B细胞。尽管我们无法在体外和体内抑制树突状细胞诱导的同种异体反应性，但DEC-205可以通过包被凹坑和囊泡迅速内化，并被递送到类似MIIC的多泡内体腔室。兔抗dec -205 IgG对兔IgG特异性T细胞杂交瘤的杀伤效率是正常兔IgG的100倍。考虑到DEC-205是一个具有10个c型凝集素结构域的受体，该分子可能是一种新的内吞受体，从细胞外空间捕获糖蛋白抗原到专门的抗原加工室。2)年龄相关的免疫功能障碍可归因于SAMP1小鼠树突状细胞和B细胞刺激t细胞活性的降低。这种变化主要是由于II类和CD54的表达减少，而不是CD80和CD86.3) HIV-1启动子有两个关键的转录控制：NF-kB位点和Sp1位点。因此，我们在人类和小鼠的不同细胞类型中寻找NF-kB和Sp1因子，使用许多生化和电迁移转移测定。树突状细胞高水平表达所有已知的NF-kB，但Sp1缺乏。静止T细胞缺乏活性NF-kB，但表达Spl。通过诱导异源树突状t细胞合胞体，HIV聚集了高水平的病毒启动子必需因子。这种现象会导致HIV-1在没有表面免疫刺激的情况下慢性复制。少

Dendritic cells belong to the myeloid linearge of hematopoietic cells and are the most potent in T cell activation for in the initiation of immune responses. The aim of this project is futher clarification of the functional role of dendritic cells in vivo and in vitro in relation to the cellular development and maturation.1) The NLDC-145 mAb recognizes a 205 kDa integral membrane protein which is expressed at high levels on murine dendritic cells and thymic epithelial cells (DEC-205). We reexamined cell specificity by mean of cytofluorographic and histological approaches and potential function of this molecule. DEC-205 can also be detected on many other subsets of leukocytes, particularly B cells. Although we have been unable to inhibit the alloreactivity that is induced by dendritic cells in vitro and in vivo, DEC-205 is shown to be rapidly internalized via coated pits and vesicles, and delivered to a multivesicular endosomal compartment resembling MIIC.A rabbit anti-DEC-205 IgG is pr … More esented by DCs to rabbit IgG-specific T cell hybridomas 100 times more efficiently than normal rabbit IgG.Considering that DEC-205 is a receptor with 10 C-type lectin domains, this molecule may be a novel endocytic receptor to capture glycoprotein antigens from extracellular space to specialized antigen processing compartment.2) Age-related immunological dysfunction is demonstrated to be ascribable to the decreased T-cell stimulating activity of dendritic cells and B cells in SAMP1 mice. This change is primarily due to the reduced expression of class II and CD54, but not CD80 and CD86.3) The HIV-1 promoter has two key transcriptional controls : NF-kB sites and Sp1 sites. Therefore, we looked for NF-kB and Sp1 factors in different cell types from human and mouse, using many biochemical and electromobility shift assays. Dendritic cells expressed high levels of all known NF-kB,but Sp1 was lacking. Quiescent T cells lacked active NF-kB but expressed Spl.By inducing heterologous dendritic-T cell syncytia, HIV brought together high levels of the essential factors for the viral promoter. This phenomenon would lead to chronic replication of HIV-1 without ostensible immune stimulation. Less