Fig. 4: High PD-1 expression and dysfunction of liver T cells in a mouse model of E. multilocularis infection.

a Histopathological alterations in the livers of mice infected with PSC inocula during the course of infection. H&E staining of liver sections. The original magnification was at 40 ×; the scale bars indicate 500 μm. b Representative flow cytometry plots and percentages of CD4⁺ T cells expressing PD-1 [phycoerythrin-labelled (PE)] in the livers of uninfected (2 weeks, n = 5; 12 weeks, n = 6; 24 weeks, n = 6) or infected mice (2 weeks, n = 6; 12 weeks, n = 7; 24 weeks, n = 6) during the course of infection (6–7 mice). c Representative flow cytometry plots and percentages of CD8⁺ T cells expressing PD-1 in the livers of uninfected (2 weeks, n = 5; 12 weeks, n = 6; 24 weeks, n = 6) or infected mice (2 weeks, n = 6; 12 weeks, n = 7; 24 weeks, n = 6) during the course of infection. d MFI of CD4⁺ T cells or CD8⁺ T cells expressing PD-1 in the livers of uninfected (n = 6) or infected mice (n = 6) at week 24 post-infection. e, f, g Percentages of CD44⁺ (n = 4), CD69⁺ (n = 4) or Ki67⁺ cells (n = 6) among CD4⁺ T cells or CD8⁺ T cells that do or do not express PD-1 (Brilliant Violet 421^TM) in the livers of mice at week 24 post-infection. h, i Representative flow cytometry plot and percentage of granzyme B, CD107α, IFN-γ and TNF-α production in CD4⁺ T cells or CD8⁺ T cells that do or do not express PD-1 in the livers of mice at week 24 post-infection (n = 6). PSCs: protoscoleces; pv: parasitic vesicle. b–d Data were analysed using two-tailed unpaired Student’s t tests. e–i Data were analysed using a two-tailed paired Student’s t tests. All data are presented as the mean ± SD from each of at least two independent experiments. n.s., P > 0.05. Source data are provided as a Source Data file.