Fig. 8

Suppressive activity of naive CD45RA⁺ regulatory T cells (Tregs) and CD45RA⁻ memory Tregs obtained from healthy volunteers (n = 40) and systemic lupus erythematosus (SLE) patients (n = 37). Total CD4⁺CD127^low+/–CD25⁺ Tregs were isolated by magnetic-activated cell sorting (MACS), stained with anti-CD45RA and CD45RO monoclonal antibodies and sorted into CD45RA⁻ memory Tregs (P1) and naive CD45RA⁺ Tregs (P2) (a). The suppressive activity of both Treg subsets was estimated with autologous Tresp for healthy volunteers (black diamonds) and SLE patients (red diamonds). The figure shows the individual and median values of the maximum suppressive activity (Treg/Tresp = 1/2) and of the ratio of Treg to Tresp up to which the purified CD45RA⁺ and CD45RA⁻ Treg subsets could be diluted to achieve a minimum suppressive activity of at least 15% (b and c). In healthy volunteers, the suppressive activity of both Treg subsets increased significantly with age. However, this could not be sustained for SLE patients (b and c). Furthermore, the suppressive activity of both Treg subsets obtained from healthy volunteers (n = 14) and SLE patients (n = 14) was tested with nonautologous Tresps of age-matched SLE patients and nonautologous Tresps of age-matched healthy volunteers. The suppressive activity of both Treg subsets from SLE patients was significantly reduced when tested with both autologous and nonautologous Tresps of healthy volunteers (d and e)