支气管肺发育不良（BPD）是一种慢性肺部疾病，通常在早产儿中常见。它通常可以由数种病理过程引起，这些过程会危及长期的肺部发育，如炎症和免疫功能紊乱。本研究采用生物信息学方法鉴定差异表达的免疫相关基因（DEIRGs）。我们从基因表达聚合物（GEO）数据库下载了转录谱（GSE32472数据集），并进行了基因集富集分析（GSEA）。细胞类型通过估计RNA转录物的相对子集（CIBERSORT）、微环境细胞种群计数器（MCPcounter）和使用表达数据在恶性肿瘤组织中估计基质和免疫细胞（ESTIMATE）用于BPD的免疫细胞浸润景观分析。随后使用加权基因共表达网络分析（WGCNA）构建了一个加权共表达网络，以筛选候选的差异表达免疫相关基因（DEIRGs）。GSEA结果显示，免疫相关途径主要涉及BPD。在BPD和正常组之间观察到了10种显着不同的免疫细胞类型。共识模块中鉴定了228个DEGs，进一步鉴定了31个DEIRGs。集群差异化8α（CD8A）表达在BPD中下调，并通过GSE25286、GSE25293、GSE99633数据集和qRT-PCR验证了其表达。此外，CD8A表达与免疫细胞浸润，特别是T细胞CD8和中性粒细胞密切相关。BPD和正常组之间发现了不同的免疫细胞浸润景观。CD8A可以成为BPD的新型候选生物标志物，通过破坏免疫细胞的功能，在高氧相关的BPD的发生和进展中发挥重要作用。©2023 Du等。

Bronchopulmonary dysplasia (BPD) refers to a chronic lung disease which is commonly observed in preterm infants. It can usually be caused by several pathological processes that endanger the long-term lung development, such as inflammation and immune dysfunction.In this study, a bioinformatics approach was applied to identify the differentially expressed immune-related genes (DEIRGs). We downloaded the transcriptional profiles (GSE32472 dataset) from the Gene Expression Omnibus (GEO) database and performed gene set enrichment analysis (GSEA). Cell type Identification By Estimating Relative Subsets of RNA Transcripts (CIBERSORT), microenvironment cell populations counter (MCPcounter), and Estimation of STromal and Immune cells in Malignant Tumor tissues using Expression data (ESTIMATE) were used for the analysis of the immune cell infiltration landscape of BPD. A weighted co-expression network was subsequently constructed using weighted gene co-expression network analysis (WGCNA) to screen candidate differentially expressed immune related genes (DEIRGs).GSEA results indicated that immune-related pathways were mainly involved in BPD. Ten significantly different immune cell types were observed between BPD and normal groups. A total of 228 DEGs in the turquoise module were identified, and 31 DEIRGs were further identified. Cluster of the differentiation 8 alpha (CD8A) expression was down-regulated in BPD, and its expression was validated by the GSE25286, GSE25293, GSE99633 datasets and qRT-PCR. In addition, CD8A expression was closely associated with immune cells infiltration, especially T cells CD8 and neutrophil.A distinct immune cell infiltration landscape was found between BPD and normal group. CD8A can be a novel candidate biomarker for BPD, which plays an essential role in the onset and progress of hyperoxia-related BPD via the disruption of immune cell functions.© 2023 Du et al.