CD4 and systemic lupus erythematosus: To evaluate whether the higher regulatory activity of CD4+CD25low/-GITR+ cells from SLE patients depended on the number of CD4+CD25low/-GITR+ cells, we correlated the percentage of CD4+CD25low/-GITR+ cells in CD4+ cells from HC and SLE patients with the inhibition of proliferation of effectors from the same subjects by CD4+CD25low/-GITR+ cells (Figure 7D).