Fig. 4

Changes in the Ki67 expression of recent thymic emigrant (RTE), mature naive (MN), CD31⁺, and CD31⁻ memory regulatory T cells (Tregs)/responder T cells (Tresps) with age in healthy volunteers (n = 94) and SLE patients (n = 78). The percentages of Ki67⁺ cells within RTE Tregs/Tresps, MN Tregs/Tresps, CD31⁺ memory Tregs/Tresps, and CD31⁻ memory Tregs/Tresps were determined in both healthy volunteers (black diamonds) and SLE patients (red diamonds) (a and b). The figures present the regression lines concerning the changes of Ki67 expression of the individual Treg/Tresp subsets with age. Significant changes with age are marked by black p values (healthy volunteers) or red p values (SLE patients). The age-independent significantly decreased (red downward arrow) percentage of Ki67⁺ cells within CD31⁺ memory Tregs and CD31⁻ memory Tregs (marked by red p* values) suggests an increased differentiation of the RTE Tregs via CD31⁺ memory Tregs into CD31⁻ memory Tregs in SLE patients (bold arrows), which is strongly suppressed by the immunosuppressive therapy (a and c). The age-independent significantly increased (red upward arrow) percentage of Ki67⁺ cells within all Tresp subsets (marked by red p* values) suggests an increased differentiation of the RTE Tresps via both MN and CD31⁺ memory Tresps into CD31⁻ memory Tresps in SLE patients (bold arrows) which is not completely suppressed by the immunosuppressive therapy (b and d)