Fig. 1

AECOPD-related DEGs identified by differential expression analysis. A The number of DEGs between the stable COPD group and the control group, the AECOPD group and the control group, the AECOPD group and the stable COPD group, respectively. B The Volcano Plot of DEGs. Each point in the Volcano Plot represents a gene, the horizontal axis represents the − log₂ (fold change) of a gene expression in two groups. − log₁₀ (p value) as the ordinate represents the statistical significance of the change in gene expression. The yellow dots, green dots and purple dots represent up-regulated, down-regulated and non-differentially expressed genes, respectively. C According to the disease progression to screen DEGs. D The clustering heat maps of DEGs. The abscissa represents the three groups, the ordinate represents the DEGs and the clustering results of the genes. The color represents the gene expression level, the deeper the red color, the higher the gene expression level