Fig. 2.

IMiDs reduce the suppressive effects of Tregs on Teffs. a Tregs were purified by FACS based on a CD4⁺ CD127^low CD25^high phenotype. The expression of CD25 and CD127 on either purified CD4⁺ T cells or purified Tregs is shown on the flow cytometry plots. b Purified CD8⁺ T cells from MM patients (‘Teffs’) were labeled with CellTrace Violet, stimulated with anti-CD3 and anti-CD28-coated microbeads and co-cultured with FACS purified autologous Tregs at different ratios. After 6 days of co-culture, the CD8⁺ T-cell proliferation was determined by flow cytometry and the cytokine concentration in the culture supernatants was determined by ELISA. In panels A–B, one representative out of four experiments is shown. c The percentage suppression of CD8⁺ T-cell proliferation and cytokine production was calculated as 100 % − (T-cell response in condition with Tregs/T-cell response in condition without Tregs) * 100 %. Each symbol represents the mean of four experiments, and the error bar represents the SEM. All statistically significant differences are indicated: *p < 0.05