Fig. 6.

ZA inhibits the immunosuppressive function of Treg cells. a Treg cells were treated with 0, 50, or 100 μM ZA for 24 h, and co-cultured with autologous anti-CD3/CD28-stimulated PBMCs for 7 h. The percentage of CD69 expression on effector T cells was analyzed by flow cytometry. b Treg cells were pretreated with CM from MDA-MB-231 cells for 72 h, followed by 0, 50, 100 μM ZA treatment for 24 h. The Tregs were then co-cultured with autologous anti-CD3/CD28-stimulated PBMCs for 7 h. The percentage of CD69 expression on effector T cells was analyzed by flow cytometry. c and d The percent suppression of the Tregs on effector T-cell without (c) and with (d) pretreated by CM from MDA-MB-231 cells after ZA treatment. The percent suppression was calculated by the following formula: 100–[(% CD69-positive in presence of Tregs/% CD69-positive in absence of Tregs) × 100]. Values shown are means ± SEM of results from four independent experiments performed in duplicate. *P < 0.05