Comparative Analysis of Host Responses Between Sepsis and COVID-19: A Prospective Observational Study of Whole Blood Transcriptome (RNA-Seq)

This prospective observational study conducted at Osaka University Graduate School of Medicine aimed to compare host responses in sepsis and COVID-19 patients by analyzing mRNA and miRNA profiles. They included 22 sepsis patients, 35 COVID-19 patients, and 15 healthy subjects. Sepsis was diagnosed using Sepsis-3 criteria, while COVID-19 was confirmed through SARS-CoV-2 RT-PCR testing and chest CT scans for pneumonia assessment. For RNA sequencing, 14,500 mRNAs, 1121 miRNAs, and 2556 miRNA-targeted mRNAs were available for analysis in sepsis patients. Numbers of genes showing upregulated:downregulated gene expression (false discovery rate <0.05, |log2 fold change| >1.5) were 256:2887 for mRNA, 53:5 for miRNA, and 49:2507 for miRNA-targeted mRNA. Similarly, in COVID-19 patients, 14,500 mRNAs, 1121 miRNAs, and 327 miRNA-targeted mRNAs were analyzed, with numbers of genes exhibiting upregulated:downregulated gene expression of 672:1147 for mRNA, 3:4 for miRNA, and 165:162 for miRNA-targeted mRNA. Sepsis patients had a greater number of upregulated and downregulated genes and pathways compared to COVID-19 patients, indicating a dynamic change in gene expression and pathway activation in sepsis. We performed the single RNA-seq analysis using whole blood from 22 sepsis patients and 35 COVID-19 patients admitted to our department, as well as 15 healthy subjects.