Table 1.

Characteristics of sepsis patients and healthy controls

Figure 1.

The transcriptional profiles of neutrophils from patients with sepsis differed from those of healthy controls. A: the protocol of isolation of neutrophils from healthy controls (n=3) and patients with sepsis (n=3); B: the top-200 genes with differential expression (fold change greater than two-fold) in neutrophils from patients with sepsis compared with those in healthy controls were selected for heat map analyses; each column depicts one sample; C: enrichment analyses of differentially expressed genes were performed (using the Gene Ontology database) to evaluate enriched biological processes between neutrophils from patients with sepsis and healthy controls; enrichment of regulation of negative regulation of T cell activation-related biological processes was included.

Figure 2.

Differentially expressed genes (DEGs) analysis and gene set enrichment analysis (GSEA) of neutrophils. A: heat map of negative regulation of T cell activation-related genes with differential expression in neutrophils from patients with sepsis compared with those from healthy controls; B: GSEA revealed an increase in negative regulation of T cell activation processes in neutrophils from patients with sepsis compared with that in healthy controls. NES: normalized enrichment score; FDR: false discovery rate.

Figure 3.

Neutrophils expression of arginase-1 in patients with sepsis. A-D: ARG1, IL-10, PAG1, and RUNX1 expression in neutrophils from patients with sepsis and healthy controls, as assessed by qRT-PCR. Data were representative of six experiments; E: representative histograms (left) and percentage statistics (right) calculated for the expression of arginase-1 in neutrophils of patients with sepsis (red; n = 6) and healthy controls (blue; n = 6). Data were analyzed by two-tailed unpaired Student’s t-test; data were presented as mean ± standard deviation.

Figure 4.

Inhibition of arginase-1 signaling elevates the percentage of polyfunctional effector CD8+ T cells. A: representative histograms showing the analysis of arginase-1 expression in neutrophils of two patients with sepsis after being treated with arginase inhibitor 1; B: the protocol of the isolation of CD8+ T cells from patients with sepsis and healthy controls; and CD14-CD15+CD16+ neutrophils from patients with sepsis. Purified CD8+ T cells from healthy controls were cocultured with neutrophils (ratio = 3:1), treated with or without arginase inhibitor 1 (10 μmol/L); C and D: PBMCs of septic patients (red), or CD8+ T cells purified from healthy controls and cocultured with neutrophils, and treated with (blue) or without (purple) arginase inhibitor 1 (10 μmol/L) overnight, or PBMCs of healthy controls (black), were stimulated with PMA for 4 h. CD8+ T cells were gated for analysis. Representative flow cytometry plots (C) and pool data (D) of the proportion of IFN-γ and granzyme B coexpression, IFN-γ and TNF-α coexpression, IFN-γ and CD107a coexpression, as well as CD107a and granzyme B coexpression by CD8+ T cells. n 6. For (D), data were analyzed by one-way ANOVA with Tukey’s multiple comparisons test; Data are presented as mean ± standard deviation.