Therefore, it seems that despite the immunosuppressive therapy, an increased ICOS+-Tresp cell differentiation via CD31+-memory-Tresps (Figure 1G) as well as an increased ICOS−-Tresp cell differentiation via resting MN-Tresps (Figure 1H) still occurs in SLE remission patients, which is counteracted by the increased differentiation of both ICOS+ and ICOS−-RTE-Tregs via resting MN-Tregs. Here, PECAM1 is linked to systemic lupus erythematosus.