Department of Molecular Biotechnology, Helmholtz Centre for Infection Research, Brunswick, Germany.
PLoS One. 2011 Apr 11;6(4):e18543. doi: 10.1371/journal.pone.0018543.
The family of type I interferons (IFN), which consists of several IFN-α and one IFN-β, are produced not only after stimulation by viruses, but also after infection with non-viral pathogens. In the course of bacterial infections, these cytokines could be beneficial or detrimental. IFN-β is the primary member of type I IFN that initiates a cascade of IFN-α production. Here we addressed the question which cells are responsible for IFN-β expression after infection with the intracellular pathogen Listeria monocytogenes by using a genetic approach. By means of newly established reporter mice, maximum of IFN-β expression was observed at 24 hours post infection in spleen and, surprisingly, 48 hours post infection in colonized cervical and inguinal lymph nodes. Colonization of lymph nodes was independent of the type I IFN signaling, as well as bacterial dose and strain. Using cell specific reporter function and conditional deletions we could define cells expressing LysM as the major IFN-β producers, with cells formerly defined as Tip-DCs being the highest. Neutrophilic granulocytes, dendritic cells and plasmacytoid dendritic cells did not significantly contribute to type I IFN production.
I 型干扰素（IFN）家族由几种 IFN-α 和一种 IFN-β 组成，不仅在病毒刺激后产生，而且在非病毒病原体感染后也会产生。在细菌感染过程中，这些细胞因子可能有益也可能有害。IFN-β 是启动 IFN-α 产生级联反应的 I 型 IFN 的主要成员。在这里，我们通过遗传方法解决了感染细胞内病原体李斯特菌后哪些细胞负责 IFN-β 表达的问题。通过新建立的报告小鼠，在感染后 24 小时观察到脾脏中 IFN-β 的最大表达，令人惊讶的是，在感染后 48 小时在定植的颈淋巴结和腹股沟淋巴结中观察到 IFN-β 的最大表达。淋巴结的定植不依赖于 I 型 IFN 信号，也不依赖于细菌剂量和菌株。使用细胞特异性报告功能和条件性缺失，我们可以定义表达 LysM 的细胞为主要的 IFN-β 产生细胞，其中以前定义为 Tip-DC 的细胞表达最高。中性粒细胞、树突状细胞和浆细胞样树突状细胞对 I 型 IFN 产生没有显著贡献。
