https://scholars.lib.ntu.edu.tw/handle/123456789/160488
Title: | CD8 T 細胞在對胞內菌保護性免疫反應的角色(2/3) | Authors: | 伍安怡 | Issue Date: | 2003 | Publisher: | 臺北市:國立臺灣大學醫學院免疫學研究所 | Abstract: | 許多新的資料顯示”外源性的”抗原可以在抗原呈獻細胞經由 MHC class I 的路徑呈獻給 CD8 T 細胞。因此CD8 T 細胞在對非病毒胞內寄生菌保護免疫 反應的角色有必要再探討。本實驗室的實驗結果顯示,除了 CD4 T 細胞外,CD8 T 細胞也參與對胞內菌Histoplasma 感染產生干擾素γ 的反應中。雖然 CD4 T 細胞的反應強度較CD8 T 細胞強,二種細胞反應之擴張與收縮的動力學則是相 同的模式。更進一步的研究結果則顯示,CD8 T 細胞在缺乏CD4 T 細胞存在的 情況下,對於抵抗Histoplasma 感染的保護性免疫反應非常重要。在 MHC class II 基因缺陷小鼠體內去除CD8 T 細胞,不但會破壞小鼠脾臟內黴菌量的維持使 之增加,還會造成小鼠在感染後五週 100% 死亡。另外,除了會分泌干擾素γ, CD8 T 細胞也具有細胞毒殺的功能,能夠毒殺Histoplasma 細胞均質液處理過 的骨髓衍生巨噬細胞。本實驗室的結果顯示,CD8 T 細胞利用產生干擾素γ 及 毒殺功能參與抵抗擴散性Histoplasma 感染的保護性免疫反應。雖然其反應較 CD4 T 細胞反應弱,但當缺乏CD4 T 細胞時,CD8 T 細胞則是非常重要的。 As new evidence showed that exogenous antigens can be presented via MHC class I pathway in professional antigen-presentation cells, the role of CD8 T cells in protective immunity against endosomal pathogen of the macrophages needs to be re-examined. Our data have shown that not only CD4 but also CD8 T cells were actively engaged in IFN γ production in response to intracellular Histoplasma infection. Although the magnitude of CD4 T cell response was greater than that of CD8 T cells, the kinetics of the expansion and contraction of both cell types followed the same pattern. Furthermore, CD8 T cells were of critical importance for the protective response against Histoplasma infection in the absence of CD4 T cells. Depletion of CD8 T cells in IIKO mice not only disrupted the maintenance of fungal load in spleens, but also caused 100% mortality after 5 weeks of infection. Moreover, as well as IFN γ production, CD8 T cells had cytotoxic activity that could lyse Histoplasma lysate-pulsed bone marrow-derived macrophages. Our results demonstrated that CD8 T cells participate in the protective immune response to disseminated infection with Histoplasma by IFN γ secretion and cytotoxicity. Although the response is minor as compared with CD4 T cells, CD8 T cells are important in the absence of CD4 T cells. |
URI: | http://ntur.lib.ntu.edu.tw//handle/246246/25359 | Other Identifiers: | 912320B002096 | Rights: | 國立臺灣大學醫學院免疫學研究所 |
Appears in Collections: | 免疫學研究所 |
File | Description | Size | Format | |
---|---|---|---|---|
912320B002096.pdf | 362.07 kB | Adobe PDF | View/Open |
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.