Department of Microbiology & Immunology, University of Michigan Medical School, Ann Arbor, MI 48109, USA.
Microb Pathog. 2010 Jul-Aug;49(1-2):38-46. doi: 10.1016/j.micpath.2010.02.004. Epub 2010 Feb 25.
Inhalational anthrax is established after inhaled Bacillus anthracis spores are transported to the lung associated lymph nodes. Dendritic cells (CD11c+ cells) located in the lungs are phagocytes that maintain many capabilities consistent with transport. This study investigates the role of dendritic cells as conduits of spores from the lung to the draining lymph nodes. The intratracheally spore-challenged mouse model of inhalational anthrax was utilized to investigate in vivo activities of CD11c+ cells. FITC labeled spores were delivered to the lungs of mice. Subsequently lung associated lymph nodes were isolated after infection and CD11c+ cells were found in association with the labeled spores. Further investigation of CD11c+ cells in early anthrax events was facilitated by use of the CD11c-diphtheria toxin (DT) receptor-green fluorescent protein transgenic mice in which CD11c+ cells can be transiently depleted by treatment with DT. We found that the presence of CD11c+ cells was necessary for efficient traffic of the spore to lung associated lymph nodes at early times after infection. Cultured dendritic cells were used to determine that these cells are capable of B. anthracis spore phagocytosis, and support germination and outgrowth. This data demonstrates that CD11c+ cells are likely carriers of B. anthracis spores from the point of inhalation in the lung to the lung associated lymph nodes. The cultured dendritic cell allows for spore germination and outgrowth supporting the concept that the CD11c+ cell responsible for this function can be a dendritic cell.
吸入性炭疽是在吸入炭疽芽孢杆菌孢子后被运送到肺部相关淋巴结而建立的。位于肺部的树突状细胞(CD11c+细胞)是吞噬细胞,具有许多与运输一致的功能。本研究调查了树突状细胞作为孢子从肺部运送到引流淋巴结的通道的作用。利用吸入性炭疽的气管内孢子挑战小鼠模型来研究 CD11c+细胞的体内活性。将 FITC 标记的孢子递送到小鼠肺部。随后,在感染后分离肺部相关淋巴结,并发现 CD11c+细胞与标记的孢子有关。通过使用 CD11c-白喉毒素(DT)受体-绿色荧光蛋白转基因小鼠进一步研究早期炭疽事件中的 CD11c+细胞,其中可以通过 DT 处理暂时耗尽 CD11c+细胞。我们发现,在感染后早期,CD11c+细胞的存在对于孢子向肺部相关淋巴结的有效运输是必要的。培养的树突状细胞用于确定这些细胞能够吞噬炭疽芽孢杆菌孢子,并支持孢子萌发和生长。这些数据表明,CD11c+细胞可能是炭疽芽孢杆菌孢子从肺部吸入点到肺部相关淋巴结的携带者。培养的树突状细胞允许孢子萌发和生长,支持负责此功能的 CD11c+细胞可以是树突状细胞的概念。