Fig. 6
Gating Strategy for identifying terminal ileum intraepithelial T lymphocytes (IEL)-CD4+ tissue-resident T memory cell subsets (TRM) and impact of oral Ty21a-immunization on IEL CD4+ TRM subsets frequencies. Terminal ileum intraepithelial lymphocytes (IEL) were isolated and IEL CD4+ TRM studied in Ty21a vaccinated, and unvaccinated individuals using a combination of CD69 and CD103 markers. a Representative gating strategies for a Ty21a vaccinated and an unvaccinated participant are shown. b The frequencies of terminal ileum IEL CD4+ T and CD8+ T cells were determined and compared between TI IEL obtained from Ty21a-vaccinated (n = 17; red symbols) and unvaccinated volunteers (n = 17; black symbols). c The frequencies of terminal ileum IEL CD4+CD103+ and CD4+CD103− TRM cells were determined and compared between TI IEL obtained from Ty21a-vaccinated (n = 17; red symbols) and unvaccinated volunteers (n = 17; black symbols). Significant differences are shown (*p < 0.05; **p < 0.005; ***p < 0.0005). Horizontal bars represent median values