Cai Yuhang, Fan Yuchen, Chen Ao, Wang Xiaohua, Wang Lulin, Chen Jiaqi, Wang Zhang, Li Jia, Yi Xinzhu, Ju Chunrong
State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guang Dong, China.
Institute of Ecological Sciences, School of Life Sciences, South China Normal University, Guangzhou, Guang Dong, China.
Respir Res. 2025 Apr 25;26(1):160. doi: 10.1186/s12931-025-03235-4.
The composition and characteristics of airway microbiota offer critical insights for clinical decision-making. Current research on chronic lung diseases shows differences in the composition and characteristics of upper and lower respiratory tract microbiota compared with healthy individuals. However, the temporal changes of these microbial communities in lung transplant recipients remain poorly characterized.
This is a longitudinal prospective study. Respiratory specimens were collected regularly from lung transplant recipients for testing and analysis. A total of 150 bronchoalveolar lavage fluid (BALF) samples, 150 throat swab samples, 51 sputum samples, and 36 lung tissue samples were collected from the recipients, at 7 days, 14 days, 1 month, 2 months, 3 months, and 6 months post-transplant for 16S rRNA gene sequencing and analysis.
Our study showed that there were significant differences in α-diversity and β-diversity among lung tissue, throat swab, and sputum samples, although α-diversity did not show a significant difference between lung tissue and BALF. Most amplicon sequence variants (ASVs) belonged to the families Enterobacteriaceae, Pseudomonadaceae, and Stenotrophomonas in BALF, while most ASVs belonged to the genera Streptococcus, Pseudomonadaceae, and Stenotrophomonas in sputum samples. Regarding dynamic changes, Corynebacterium and Staphylococcus were more prevalent in the early post-operative period but gradually decreased by 7 days post-operatively, while the common microbiota found in healthy populations based on literature became the most abundant ASVs at 6 months post-operatively in our study participants. Pseudomonadaceae and Stenotrophomonas contributed to the similarity in the composition of upper and lower respiratory microbiota.
This study demonstrates that lung transplant recipients exhibit unique characteristics in their upper and lower respiratory tract microbiota, which are distinct ecological profiles, and both undergo significant changes within 6 months post-operatively. The similarity between upper and lower respiratory tract microbiota is associated with microbial diversity and taxonomic dominance.
The clinical trial was registered at Chinese Clinical Trial Registry (ChiCTR2200056908) in February 2022.
气道微生物群的组成和特征为临床决策提供了关键见解。目前关于慢性肺部疾病的研究表明，与健康个体相比，上、下呼吸道微生物群的组成和特征存在差异。然而，肺移植受者中这些微生物群落的时间变化仍未得到充分描述。
这是一项纵向前瞻性研究。定期从肺移植受者中采集呼吸道标本进行检测和分析。在移植后7天、14天、1个月、2个月、3个月和6个月，从受者中总共采集了150份支气管肺泡灌洗液（BALF）样本、150份咽拭子样本、51份痰液样本和36份肺组织样本，用于16S rRNA基因测序和分析。
我们的研究表明，肺组织、咽拭子和痰液样本之间的α多样性和β多样性存在显著差异，尽管肺组织和BALF之间的α多样性没有显著差异。BALF中大多数扩增子序列变体（ASV）属于肠杆菌科、假单胞菌科和嗜麦芽窄食单胞菌科，而痰液样本中大多数ASV属于链球菌属、假单胞菌科和嗜麦芽窄食单胞菌属。关于动态变化，棒状杆菌属和葡萄球菌属在术后早期更为普遍，但在术后7天时逐渐减少，而根据文献，健康人群中常见的微生物群在我们的研究参与者术后6个月时成为最丰富的ASV。假单胞菌科和嗜麦芽窄食单胞菌属导致了上、下呼吸道微生物群组成的相似性。
本研究表明，肺移植受者的上、下呼吸道微生物群具有独特的特征，这是不同的生态特征，并且在术后6个月内均发生显著变化。上、下呼吸道微生物群之间的相似性与微生物多样性和分类优势有关。
该临床试验于2022年2月在中国临床试验注册中心（ChiCTR2200056908）注册。
