Chlorovirus ATCV-1 is part of the human oropharyngeal virome and is associated with changes in cognitive functions in humans and mice

Human mucosal surfaces contain a wide range of microorganisms. The biological effects of these organisms are largely unknown. Large-scale metagenomic sequencing is emerging as a method to identify novel microbes. Unexpectedly, we identified DNA sequences homologous to virus ATCV-1, an algal virus not previously known to infect humans, in oropharyngeal samples obtained from healthy adults. The presence of ATCV-1 was associated with a modest but measurable decrease in cognitive functioning. A relationship between ATCV-1 and cognitive functioning was confirmed in a mouse model, which also indicated that exposure to ATCV-1 resulted in changes in gene expression within the brain. Our study indicates that viruses in the environment not thought to infect humans can have biological effects. Mice that had been successfully infected with ATCV-1, n=16, were compared with matched but un-infected mice, n=7.

人类黏膜表面定植着种类丰富的微生物群落，此类微生物的生物学效应迄今仍未被充分揭示。大规模宏基因组测序（metagenomic sequencing）正逐渐成为识别新型微生物的重要研究手段。令人意外的是，我们在健康成年人的口咽样本中，检测到了与藻类病毒ATCV-1同源的DNA序列——该病毒此前从未被认为可感染人类。ATCV-1的检出与认知功能出现小幅但可量化的下降存在相关性。这一ATCV-1与认知功能的关联在小鼠模型中得到了验证，同时该模型还显示，暴露于ATCV-1可导致小鼠脑内基因表达发生改变。本研究表明，此前被认为不会感染人类的环境病毒，同样可产生生物学效应。本次实验将16只成功感染ATCV-1的小鼠（n=16）与7只匹配对照但未感染的小鼠（n=7）进行了对比分析。