■脓毒症是一种危及生命的疾病,死亡率很高。已经出现了一些研究,利用单细胞RNA测序(scRNA-seq)来分析脓毒症中单细胞分辨率的基因表达。但是尚未对血液抗原呈递细胞进行全面的高分辨率分析。
■所有公开的人类scRNA-seq数据均从单细胞门户数据库下载。手动整理数据集后,我们提取了所有的抗原呈递细胞,包括树突状细胞(DC)和单核细胞,用于鉴定细胞亚群及其基因谱分析和脓毒症患者与健康对照之间的细胞间相互作用。最后,我们通过对大量RNA测序(RNA-seq)数据和流式细胞术进行去卷积分析,进一步验证了研究结果.
■在传统的DC人群中,我们发现了以低主要组织相容性复合物II类表达为特征的新型无能DC亚型。值得注意的是,这些无能DC亚型在脓毒症患者中显示显著增加.此外,我们发现以前报道的免疫抑制单核细胞亚型,Mono1表现出与这些无能DC相似的基因表达谱。通过使用大量RNA-seq和流式细胞术进行验证,证实了我们研究结果的一致性。确保准确识别细胞亚型和基因表达模式。
■这项研究代表了人类败血症中抗原呈递细胞的第一个全面的单细胞分析,揭示新的疾病相关无能DC亚型。这些发现为细菌性脓毒症免疫失调的细胞机制提供了新的见解。
Sepsis is a life-threatening condition with high mortality. A few studies have emerged utilizing single-cell RNA sequencing (scRNA-seq) to analyze gene expression at the single-cell resolution in sepsis, but a comprehensive high-resolution analysis of blood antigen-presenting cells has not been conducted.
All published human scRNA-seq data were downloaded from the single cell portal database. After manually curating the dataset, we extracted all antigen-presenting cells, including dendritic cells (DCs) and monocytes, for identification of cell subpopulations and their gene profiling and intercellular interactions between septic patients and healthy controls. Finally, we further validated the findings by performing deconvolution analysis on bulk RNA sequencing (RNA-seq) data and flow cytometry.
Within the traditional DC populations, we discovered novel anergic DC subtypes characterized by low major histocompatibility complex class II expression. Notably, these anergic DC subtypes showed a significant increase in septic patients. Additionally, we found that a previously reported immunosuppressive monocyte subtype, Mono1, exhibited a similar gene expression profile to these anergic DCs. The consistency of our findings was confirmed through validation using bulk RNA-seq and flow cytometry, ensuring accurate identification of cell subtypes and gene expression patterns.
This study represents the first comprehensive single-cell analysis of antigen-presenting cells in human sepsis, revealing novel disease-associated anergic DC subtypes. These findings provide new insights into the cellular mechanisms of immune dysregulation in bacterial sepsis.