Profiles of immune status and related pathways in sepsis: evidencebased on GEO and bioinformatics

Sepsis,characterized as life-threatening sequential organ failure,is caused by a dysregulated host immune response to a pathogen.Conventional practice for sepsis is to control the inflammation source and administer highgrade antibiotics.However,the mortality rate of sepsis varies from 25–30%and can reach 50%if a septic shock occurs.In our current study,we used bioinformatics technology to detect immune status profiles in sepsis at the genomic level.We downloaded and analyzed gene expression profiles of GSE28750 from the Gene Expression Omnibus(GEO)database to determine differential gene expression and immune status between sepsis and normal samples.Next,we used the CIBERSORT method to quantify the proportions of immune cells in the sepsis samples.Then we explored the differentially expressed genes(DEGs)related to sepsis.Furthermore,gene ontology(GO)function and the Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis were used to present potential signaling pathways in sepsis.We found that in the sepsis samples,the CD8+T cell fraction was consistently lower,based on the CIBERSORT method,whereas the neutrophil fraction was significantly higher in the sepsis samples.The GO function and KEGG pathway enrichment analysis identified 1573 DEGs that were significantly associated with neutrophil activation,neutrophil degranulation,neutrophil activation involved in the immune response,neutrophil-mediated immunity,and T cell activation in the biological processes group.In our study,we provided a first glance of associations between immune status and sepsis.Furthermore,our data regarding the reciprocal interaction between immune cells(neutrophils and CD8+T cells)could improve our understanding of immune status profiles in sepsis.However,additional investigations should be performed to verify their clinical value.