基于呼吸系统健康效应的室内空气微生物研究现状与展望

Research status and prospects of indoor airborne microbiome based on respiratory health effects

室内空气微生物是人体呼吸系统疾病的重要诱因,明确室内空气微生物与呼吸系统健康效应关系对建立室内健康微生物环境标准具有积极意义.近十多年,环境和人类呼吸道健康相关的微生物学深入研究已使人们对微生物的看法从纯粹致病性、传染性的负面作用逐渐转变为潜在保护性、预防性的正面作用.然而,目前室内空气微生物与呼吸系统的量化作用机制尚未建立,现行的公共卫生政策和室内空气微生物控制标准仍倾向于使室内保持尽可能低的微生物浓度,以防止致病菌传播和人群感染.本文总结了室内空气微生物与呼吸系统健康效应的相关研究,指出了基于呼吸道健康效应的室内空气微生物定量表征的关键理论欠缺和技术瓶颈,并以此为依据,提出了基于采样工具、统计学工具以及实验工具优化的研究展望,为未来量化呼吸系统健康效应与室内空气微生物作用的关系、室内空气微生物的表征提供借鉴.

Indoor environment is an important repository of microbiome.Environmental microbiome can influence immune protection through changing the commensal flora of the respiratory tract.The interaction between environment airborne microbiome and human microbiome contributes to human microbial diversity,provides immunomodulatory effects,and thus reduces the risk of respiratory diseases.Lack of immune modulation acquired through microbial exposure may lead to risk of chronic respiratory diseases.Clinical parameters,such as susceptibility,progression,and severity of respiratory disease,are associated with microbial changes.Chronic obstructive pulmonary disease,cystic fibrosis,asthma,and lung cancers are associated with airway microbial dysbiosis.The changes of microbiome during the disease period are mainly characterized by a decrease in overall bacterial diversity,a decrease in the number of commensal bacteria,and an increase in the number of potential pathogenic bacteria.Based on the perception that pathogenic or conditional pathogenic microbiome is responsible for the infection and transmission of respiratory and non-respiratory diseases,public health policies have long favored keeping indoors at lower concentrations of microbiome or even absolutely sterile.However,in the past decade,an in-depth understanding of the microbiology of the environment and human health has shifted researchers’view of indoor microbiome from a purely pathogenic and infectious negative role to a potentially protective,preventive positive role.Facing with the dual health effects of indoor airborne microbiome,the ideal control strategy should be to increase the microbial diversity and the proportion of beneficial microbiome,while reducing the concentration of pathogenic microbiome for regions,seasons,and sensitive populations.However,there is still no paradigm shift in built environment microbiology due to technical bottlenecks that prevent researchers from establishing a causal relationship between indoor microbiome and health effects.Currently,the types and properties of indoor airborne microbiome are yet to be fully screened and understood.The characteristics of indoor microbiome when they exert health effects are yet to quantify,including microbial metabolization and reproduction in the respiratory tract,corresponding protective effects,and dose-response effects and individual variation in health effects.The answer to the question“What is a healthy indoor air microbial environment”,that is,the characterization of indoor airborne microbiome based on respiratory health effects,is hindered by respiratory microbial sampling,in-depth analysis of microbial data,and the accuracy of in vitro experiments.Subsequent research needs to focus on the development of the following techniques:Microbial sampling tools with low invasiveness,high efficiency and low cost;statistical tools with complex source identification,interference factor quantification and causal relationship judgment functions;and experimental tools capable of simulating real,complex respiratory environments and revealing molecular mechanisms of action in vivo.“What is a healthy indoor air microbial environment”will gradually become clear as these questions are resolved.A clear and quantitative mechanism will serve as a scientific basis to guide the improvement of indoor microbial control standards and the rational use of practical interventions.