Fig. 3

Proteomic analysis of differentially expressed EV proteins in septic patients compared to HC individuals. (A) A volcano plot for the plasma EV proteins from 15 septic patients and 10 HC individuals. The x-axis represents the fold-change of septic patients/HC individuals in the Z score scale (a standardized measure that indicates how far a data point is away from the mean of a distribution. Z score of 1 presents 1 standard deviation). The y-axis represents the P value of statistical analysis in -Log₁₀ scale. The curved lines indicate the boundary for a q-value of 0.05. Proteins with q < 0.05 are differentially expressed in septic patients, and representative proteins among them are highlighted in red. (B) Principal Component Analysis (PCA) for the 522 differentially expressed EV proteins between septic (n = 15) and HC individuals (n = 10). (C) The enriched pathways in the KEGG Pathway analysis¹⁸ were displayed using the GO plot package. The GO plot shows the up/down-regulation of differentially expressed proteins in sepsis, displaying the –Log₁₀ (P value) and z-score values for each pathway. The red circles represent upregulated proteins in each pathway, while the blue circles represent downregulated proteins. The size of the trapezoids in the inner circle of the GO circle reflects the –Log₁₀ (P value) of the enriched pathway. The color of the trapezoids corresponds to the z-score. The z-score in the package is calculated as follows: z-score = (the number of upregulated proteins – the number of downregulated proteins)/square root (the number of proteins). (D) GO analysis of Cellular Components (GO-CC) describes where the differentially expressed EV proteins originate from. GO-CC enrichment analysis selected the top 11 as representative lists based on –Log₁₀ (P value). The count represents the number of enriched proteins in GO terms. The % represents the proportion of genes in the input list associated with the specific GO term.