Department of Occupational and Environmental Health, School of Public Health, Sun Yat-sen University, Guangzhou, PR China; Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, Guangdong 510642, PR China.
Occupational and Environmental Medicine, Dept. of Medical Science, University Hospital, Uppsala University, 75237 Uppsala, Sweden.
Environ Int. 2020 May;138:105664. doi: 10.1016/j.envint.2020.105664. Epub 2020 Mar 19.
Indoor microbial diversity and composition are suggested to affect the prevalence and severity of asthma by previous home microbiome studies, but no microbiome-health association study has been conducted in a school environment, especially in tropical countries. In this study, we collected floor dust and environmental characteristics from 21 classrooms, and health data related to asthma symptoms from 309 students, in junior high schools in Johor Bahru, Malaysia. The bacterial and fungal composition was characterized by sequencing 16s rRNA gene and internal transcribed spacer (ITS) region, and the absolute microbial concentration was quantified by qPCR. In total, 326 bacterial and 255 fungal genera were characterized. Five bacterial (Sphingobium, Rhodomicrobium, Shimwellia, Solirubrobacter, Pleurocapsa) and two fungal (Torulaspora and Leptosphaeriaceae) taxa were protective for asthma severity. Two bacterial taxa, Izhakiella and Robinsoniella, were positively associated with asthma severity. Several protective bacterial taxa including Rhodomicrobium, Shimwellia and Sphingobium have been reported as protective microbes in previous studies, whereas other taxa were first time reported. Environmental characteristics, such as age of building, size of textile curtain per room volume, occurrence of cockroaches, concentration of house dust mite allergens transferred from homes by the occupants, were involved in shaping the overall microbial community but not asthma-associated taxa; whereas visible dampness and mold, which did not change the overall microbial community for floor dust, was negatively associated with the concentration of protective bacteria Rhodomicrobium (β = -2.86, p = 0.021) of asthma. The result indicates complex interactions between microbes, environmental characteristics and asthma symptoms. Overall, this is the first indoor microbiome study to characterize the asthma-associated microbes and their environmental determinant in the tropical area, promoting the understanding of microbial exposure and respiratory health in this region.
室内微生物多样性和组成被先前的家庭微生物组研究表明会影响哮喘的患病率和严重程度，但在学校环境中，特别是在热带国家，尚未进行微生物组与健康的关联研究。在这项研究中，我们从马来西亚柔佛州的初中收集了 21 间教室的地板灰尘和环境特征，以及 309 名学生与哮喘症状相关的健康数据。通过测序 16s rRNA 基因和内部转录间隔区（ITS）区域，对细菌和真菌组成进行了特征描述，并通过 qPCR 定量了绝对微生物浓度。总共鉴定出 326 种细菌和 255 种真菌属。有 5 种细菌（Sphingobium、Rhodomicrobium、Shimwellia、Solirubrobacter、Pleurocapsa）和 2 种真菌（Torulaspora 和 Leptosphaeriaceae）类群对哮喘严重程度具有保护作用。两种细菌类群 Izhakiella 和 Robinsoniella 与哮喘严重程度呈正相关。以前的研究已经报道了一些保护性细菌类群，如 Rhodomicrobium、Shimwellia 和 Sphingobium 等对哮喘具有保护作用，而其他类群则是首次报道。环境特征，如建筑物的年龄、每间房的纺织品窗帘面积、蟑螂的出现、居住者从家中带入的尘螨过敏原浓度，参与塑造了整体微生物群落，但与哮喘相关的类群无关；而不会改变地板灰尘整体微生物群落的可见潮湿和霉菌，与保护性细菌 Rhodomicrobium 的浓度呈负相关（β = -2.86，p = 0.021）。结果表明微生物、环境特征和哮喘症状之间存在复杂的相互作用。总的来说，这是首次在热带地区对室内微生物组进行哮喘相关微生物及其环境决定因素的特征描述，促进了对该地区微生物暴露和呼吸道健康的理解。
