Abstract：
Although the link between microbial infections and Alzheimer\'s disease (AD) has been demonstrated in multiple studies, the involvement of pathogens in the development of AD remains unclear. Here, we investigated the frequency of the 10 most commonly cited viral (HSV-1, EBV, HHV-6, HHV-7, and CMV) and bacterial (Chlamydia pneumoniae, Helicobacter pylori, Borrelia burgdorferi, Porphyromonas gingivalis, and Treponema spp.) pathogens in serum, cerebrospinal fluid (CSF) and brain tissues of AD patients. We have used an in-house multiplex PCR kit for simultaneous detection of five bacterial and five viral pathogens in serum and CSF samples from 50 AD patients and 53 healthy controls (CTRL). We observed a significantly higher frequency rate of AD patients who tested positive for Treponema spp. compared to controls (AD: 62.2 %; CTRL: 30.3 %; p-value = 0.007). Furthermore, we confirmed a significantly higher occurrence of cases with two or more simultaneous infections in AD patients compared to controls (AD: 24 %; CTRL 7.5 %; p-value = 0.029). The studied pathogens were detected with comparable frequency in serum and CSF. In contrast, Borrelia burgdorferi, human herpesvirus 7, and human cytomegalovirus were not detected in any of the studied samples. This study provides further evidence of the association between microbial infections and AD and shows that paralleled analysis of multiple sample specimens provides complementary information and is advisable for future studies.
摘要：
尽管微生物感染与阿尔茨海默病（AD）之间的联系已在多项研究中得到证实，病原体是否参与AD的发展尚不清楚。这里,我们调查了10种最常引用的病毒(HSV-1，EBV，HHV-6，HHV-7和CMV）和细菌（肺炎衣原体，幽门螺杆菌,伯氏疏螺旋体,牙龈卟啉单胞菌,和密螺旋体属。)血清中的病原体，AD患者的脑脊液（CSF）和脑组织。我们已使用内部多重PCR试剂盒同时检测来自50名AD患者和53名健康对照（CTRL）的血清和CSF样品中的5种细菌和5种病毒病原体。我们观察到密螺旋体检测呈阳性的AD患者的频率明显更高。与对照组相比（AD：62.2%；CTRL：30.3%；p值=0.007）。此外，我们证实,与对照组相比,AD患者同时发生两种或两种以上感染的病例明显较高(AD:24%;CTRL7.5%;p值=0.029).所研究的病原体在血清和CSF中的检测频率相当。相比之下,伯氏疏螺旋体,在任何研究样品中均未检测到人疱疹病毒7型和人巨细胞病毒。这项研究提供了微生物感染与AD之间关联的进一步证据，并表明对多个样本标本的平行分析提供了补充信息，并建议用于未来的研究。
