Effects of Chlamydia trachomatis infection on the expression of natural killer (NK) cell ligands and susceptibility to NK cell lysis
Effects of Chlamydia trachomatis infection on the expression of natural killer (NK) cell ligands and susceptibility to NK cell lysis
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DOI：
10.1111/j.1365-2249.2004.02596.x
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发表时间：
2004-10-01
影响因子：
4.6
通讯作者：
Gaston, JSH
中科院分区：
文献类型：
--
作者：
Hook, CE;Telyatnikova, N;Gaston, JSH
自然杀伤（NK）细胞是对感染（包括细胞内细菌感染）的即时免疫应答的重要组成部分。我们已经研究了识别沙眼衣原体（CT）的NK细胞，并表明，这些细胞被激活产生干扰素（IFN）-γ时，外周血单核细胞（PBMC）与CT生物体刺激。此外，用CT感染上皮细胞系使它们易于被人NK细胞裂解。感染后18-24小时观察到易感性，并需要由感染的衣原体蛋白质合成，但不是由宿主细胞;热或UV灭活的衣原体不诱导NK细胞裂解的易感性。CT感染也显示出减少经典和非经典主要组织相容性复合体（MHC）分子在感染细胞上的表达，从而当与激活信号结合时允许NK细胞识别。一个候选的激活信号是云母/B，其显示在上皮细胞上组成型表达。
Natural killer (NK) cells are an important component of the immediate immune response to infections, including infection by intracellular bacteria. We have investigated recognition of Chlamydia trachomatis (CT) by NK cells and show that these cells are activated to produce interferon (IFN)-gamma when peripheral blood mononuclear cells (PBMC) are stimulated with CT organisms. Furthermore, infection of epithelial cell lines with CT renders them susceptible to lysis by human NK cells. Susceptibility was observed 18-24 h following infection and required protein synthesis by the infecting chlamydiae, but not by the host cell; heat or UV inactivated chlamydiae did not induce susceptibility to NK cell lysis. CT infection was also shown to decrease the expression of classical and non-classical major histocompatibility complex (MHC) molecules on infected cells, thus allowing recognition by NK cells when combined with an activating signal. A candidate activating signal is MICA/B, which was shown to be expressed constitutively on epithelial cells.