通过自然发生的产生TNF/iNOS的树突细胞调节IgA的产生
Hiroyuki Tezuka1, Yukiko Abe, Makoto Iwata
1Department of Immunology, Akita University Graduate School of Medicine, Akita 010-8543, Japan.
Nature
|August 24, 2007
概括
诱导性氧化合成酶 (iNOS) 对于肠道IgA产生至关重要. 这种酶调节免疫细胞中的IgA类切换重组,解释了为什么肠道比其他组织产生更多的IgA.
科学领域:
- 免疫学 免疫学 免疫学
- 微生物学 微生物学
- 细胞生物学 细胞生物学
背景情况:
- 免疫球蛋白-A (IgA) 对粘膜免疫对病原体至关重要.
- 与其他淋巴细胞器官相比,粘膜相关淋巴细胞组织 (MALT) 的IgA产生存在显著偏差.
研究的目的:
- 调查在MALT中偏好的IgA合成背后的分子机制.
- 确定可诱导氧化合成酶 (iNOS) 在IgA类交换重组 (CSR) 中的作用.
主要方法:
- 使用iNOS-缺乏 (iNOS-/-) 的小鼠来研究IgA CSR.
- 分析了T细胞依赖性和T细胞独立性IgA CSR通路.
- 研究了MALT树突细胞的作用,以及它们通过类似收费的受体与共生细菌的相互作用.
主要成果:
- 在INOS-/-小鼠中,IgA CSR受损.
- iNOS通过转化生长因子-β受体 (T细胞依赖) 和通过产生增殖诱导配体 (APRIL) 和B细胞激活因子 (BAFF) (T细胞独立) 来调节IgA CSR.
- 在识别共生细菌时,iNOS在MALT树突细胞中得到表达,这些细胞可以在iNOS-/-小鼠中挽救IgA的产生.
结论:
- 在MALT树突细胞中的iNOS对于肠道中偏向的IgA产生至关重要.
- 在MALT中产生TNF-alpha/iNOS的树突细胞子集在通过IgA生产来维持肠道平衡中起着至关重要的作用.
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