Fig. 1

CD4CD8αα IELs predominantly exhibit enhanced cytotoxicity in septic mice. IELs were isolated from small intestines harvested from WT mice 4 h after sham or CLP surgery. (A) Representative gating strategy of flow cytometry plots for detecting live CD4CD8αα cells in IELs. (B) Percentage and (C) absolute number of CD4CD8αα IELs isolated from sham and CLP mice. Experiments were performed 3 times, and all data were used for analysis. Data represent the mean ± SEM (n = 5/group). The groups were compared by Student’s t-test. (D) Unsupervised clusterization of live TCRβ⁺CD4⁺ cells from the flow cytometry dataset of IELs in sham and sepsis mice was conducted using the t-distributed stochastic neighbor embedding (t-SNE) algorithm (each group is n = 15,000 from 6 mice). Heatmap density plots of CD8α, CD8β, GrB, and Prf were generated according to the median fluorescence intensity (MFI). Areas surrounded by dashed lines in CD4CD8αα population denote where GrB and Prf are highly expressed, and their intensities and cell numbers are increased after sepsis. CD4CD8αα IELs were isolated by FACS to determine the mRNA levels of (E) GrB and (F) Prf. Experiments were performed 2 times, and all data were used for analysis. Data represent the mean ± SEM (n = 4/group). The groups were compared by Student’s t-test. *p < 0.05 vs. sham