Figure 2: Peyer’s patches contain resident CD4⁺ T cells.

(a) Frequency of D-Red⁺ among all CD4⁺ (left) ), CD4⁺CD62L^hi (middle) and CD4⁺CD62L^lo (right) T cells 7 days after photoconversion of PPs (n=5 mice in three independent experiments, mean±s.d., one-way analysis of variance (ANOVA), Tukey’s post test, ***P<0.001; not significant (NS)). (b) Frequency of CD62L^hi and CD62L^lo cells among CD4⁺ (left) or CD4⁺D-Red⁺ (right) T cells 7 days after photoconversion of PPs from data in a (mean±s.d.). (c) Frequency of FITC⁺ among all CD4⁺ (left), CD4⁺CD62L^hi (middle) and CD4⁺CD62L^lo (right) T cells 7 days after FITC injection into PPs (n=8 mice in two independent experiments, mean±s.d., one-way ANOVA, Tukey’s post test, **P<0.01; ***P<0.001; not significant (NS)). (d) Frequency of CD62L^hi and CD62L^lo cells among CD4⁺ (left) or CD4⁺D-Red⁺ (right) T cells 7 days after FITC injection into PPs from data in c (mean±s.d.). (e) Frequency of D-Red⁺ (red bars) and D-Red⁻ (grey bars) among CD4⁺ T cells in PP_conv 7, 14 and 28 days after (n=3 mice per time-point in two independent experiments, mean±s.d.) (f) CD62L expression on CD4⁺ T cells 7 days after FITC injection into PPs (representative of three independent experiments, n=18 mice, mean±s.d.).