稳态下肺新型调节性树突状细胞亚群的初步鉴定

Identification of novel regulatory dendritic cell subsets in the lung at steady state

目的初步鉴定肺新型调节性树突状细胞(dendritic cell,DC)亚群的表型特征及功能特性。方法通过单细胞转录组测序(single-cell RNA sequence,scRNA-seq)及生物信息学分析技术解析肺DC各亚群的基因表达特征;利用流式细胞术进一步分析肺新型调节性DC亚群的表型特征;此外,结合体外细胞共培养体系和流式细胞术探究肺新型调节性DC亚群的功能特性。结果单细胞数据分析显示,在稳态条件下肺组织中存在一群独立且不同于经典DC1(conventional DC1,cDC1)、经典DC2(conventional DC2,cDC2)和浆样DC(plasmacytoid DC,pDC),并特异性高表达Ccr7、Cd80等成熟DC特征基因以及Cd274等负向调控基因的肺新型调节性DC亚群(regulatory DC,DCreg);流式分析数据进一步验证了DCreg在肺组织中的存在,并具有显著性高表达共刺激分子CD80、CD86的表型特征;体外细胞共培养实验结果表明,肺DCreg可促进Treg产生。结论在稳态条件下,初步发现一群独立且不同于c DC1、c DC2和pDC,并可体外促进Treg产生的肺新型调节性DC亚群。

Objective:To identify a novel regulatory dendritic cell(DC)subsets in the lung at steady state.Methods:The gene expression characteristics of each subset of lung DCs were analyzed by single-cell RNA sequence(scRNA-seq)and bioinformatics analysis techniques;the phenotypic profile of novel regulatory DC subsets in the lung were further analyzed by flow cytometry;in addition,the functional characteristics of novel regulatory DC subsets in the lung were explored in combination with in vitro cell co-culture system and flow cytometry.Results:Single cell data showed that there was a population of DC subsets transcriptionally distinct from cDC1,cDC2 and pDCs in lung tissues under steady-state.As this DC subset highly expressed mature DC signature genes,such as Ccr7 and Cd80 as well as negative regulatory genes,such as Cd274,we named them regulatory DCs(DCreg).Flow analysis data further confirmed the existence of DCreg in lung tissues,which highly expressed costimulatory molecules CD80 and CD86;in vitro cell co-culture experiments showed that functionally lung DCreg could promote Treg production.Conclusion:Preliminary discovery shows a novel lung regulatory DC subset in the lung that is independent and distinct from cDC1,cDC2,and pDC,and can promote Treg production in vitro.