Wolf Katerina, Fischer Elizabeth, Hackstadt Ted
Host-Parasite Interactions Section, Laboratory of Intracellular Parasites, NIAID, NIH, Rocky Mountain Laboratories, Hamilton, MT 59840, USA.
Infect Immun. 2005 Aug;73(8):4560-70. doi: 10.1128/IAI.73.8.4560-4570.2005.
Chlamydia pneumoniae is a common human respiratory pathogen that has been associated with a variety of chronic diseases, including atherosclerosis. The role of this organism in the pathogenesis of atherosclerosis remains unknown. A key question is how C. pneumoniae is transferred from the site of primary infection to a developing atherosclerotic plaque. It has been suggested that circulating monocytes could be vehicles for dissemination of C. pneumoniae since the organism has been detected in peripheral blood monocytic cells (PBMCs). In this study we focused on survival of C. pneumoniae within PBMCs isolated from the blood of healthy human donors. We found that C. pneumoniae does not grow and multiply in cultured primary monocytes. In C. pneumoniae-infected monocyte-derived macrophages, growth of the organism was very limited, and the majority of the bacteria were eradicated. We also found that the destruction of C. pneumoniae within infected macrophages resulted in a gradual diminution of chlamydial antigens, although some of these antigens could be detected for days after the initial infection. The detected antigens present in infected monocytes and monocyte-derived macrophages represented neither chlamydial inclusions nor intact organisms. The use of {N-[7-(4-nitrobenzo-2-oxa-1,3-diazole)]}-6-aminocaproyl-d-erythro-sphingosine as a vital stain for chlamydiae proved to be a sensitive method for identifying rare C. pneumoniae inclusions and was useful in the detection of even aberrant developmental forms.
肺炎衣原体是一种常见的人类呼吸道病原体，与包括动脉粥样硬化在内的多种慢性疾病有关。这种微生物在动脉粥样硬化发病机制中的作用尚不清楚。一个关键问题是肺炎衣原体如何从原发性感染部位转移到正在形成的动脉粥样硬化斑块中。有人提出循环单核细胞可能是肺炎衣原体传播的载体，因为在外周血单核细胞（PBMCs）中已检测到该微生物。在本研究中，我们重点关注从健康人类供体血液中分离出的PBMCs内肺炎衣原体的存活情况。我们发现肺炎衣原体在培养的原代单核细胞中不生长和繁殖。在感染肺炎衣原体的单核细胞衍生巨噬细胞中，该微生物的生长非常有限，并且大多数细菌被清除。我们还发现，感染巨噬细胞内肺炎衣原体的破坏导致衣原体抗原逐渐减少，尽管在初次感染后的数天内仍可检测到一些这些抗原。在感染的单核细胞和单核细胞衍生巨噬细胞中检测到的抗原既不代表衣原体包涵体也不代表完整的生物体。使用{N-[7-(4-硝基苯并-2-恶唑-1,3-二氮杂环戊二烯)]}-6-氨基己酰基-d-赤藓糖神经鞘氨醇作为衣原体的活体染色剂，被证明是鉴定罕见肺炎衣原体包涵体的灵敏方法，并且在检测甚至异常发育形式方面也很有用。
