Ring R H, Lyons J M
Division of Neurosciences, Beckman Research Institute at the City of Hope, Duarte, California 91010, USA.
J Clin Microbiol. 2000 Jul;38(7):2591-4. doi: 10.1128/JCM.38.7.2591-2594.2000.
Epidemiological studies have yet to identify a single cause for the most common late-onset form of Alzheimer's disease. The common respiratory pathogen Chlamydia pneumoniae recently has been implicated as a risk factor for this form of Alzheimer's disease. Were this true, there would be a dramatic shift in current paradigms of Alzheimer's disease research and treatment. In the absence of published confirmation, we obtained postmortem brain tissue from late-onset Alzheimer's disease patients (n = 15) and representative controls (n = 5) and extracted DNA from up to six separate brain regions in each instance, including those areas particularly relevant to Alzheimer's disease neuropathology. Each sample of DNA (n = 101) was assayed five times or more for the presence of C. pneumoniae DNA using a nested-PCR protocol targeting a species-specific gene sequence coding for the major outer membrane protein of this organism. We were unable unequivocally to detect C. pneumoniae in any of the 101 samples tested by PCR and failed to culture the organism from tissue samples. We conclude that C. pneumoniae is neither strongly nor uniquely associated with the neuropathology seen in late-onset Alzheimer's disease.
流行病学研究尚未确定最常见的晚发型阿尔茨海默病的单一病因。常见呼吸道病原体肺炎衣原体最近被认为是这种形式的阿尔茨海默病的一个风险因素。如果这是真的，阿尔茨海默病研究和治疗的当前范式将会发生巨大转变。在缺乏已发表的确证的情况下，我们从晚发型阿尔茨海默病患者（n = 15）和代表性对照者（n = 5）获取了尸检脑组织，并在每种情况下从多达六个不同的脑区提取DNA，包括那些与阿尔茨海默病神经病理学特别相关的区域。使用针对编码该生物体主要外膜蛋白的物种特异性基因序列的巢式PCR方案，对每个DNA样本（n = 101）进行了五次或更多次检测，以确定是否存在肺炎衣原体DNA。我们无法通过PCR在测试的101个样本中的任何一个中明确检测到肺炎衣原体，并且未能从组织样本中培养出该生物体。我们得出结论，肺炎衣原体与晚发型阿尔茨海默病中所见的神经病理学既没有强烈关联也没有独特关联。
