IMiD pretreatment further improved AMG 701–induced T-cell differentiation, CD8/CD4 ratios, and Tscm, and suppressed immune inhibitory regulators in ex vivo cocultures. (A) AMG 701 (46.7 pM) was added into cocultures of H929 with IMiD-pretreated (len or pom, 1 μM) or control (ctrl) patient T cells (n = 3) (E:T = 5:1) on day 0 (d0). Quantitative FC analysis was used to evaluate the percentage of CM and EM in T subsets (left) and the CD8/CD4 ratios (right) at the same time interval. (B) Similar analysis as in panel A was done in the presence of OC using additional T cells (n = 3). (C) Shown are time- and dose-dependency studies on the percentage of Tscm in T subsets (n = 3) in IMiD-pretreated vs ctrl T cells from patients cocultured with H929 MM targets (E:T = 5:1) in the presence of AMG 701. CD8/CD4 ratios at day 7 cocultures were also evaluated (D). (E) Patient T cells (n = 3) treated with 1 μM len, pom, or medium (ctrl) were cocultured with H929 target cells (E:T=5:1) in serial concentrations of AMG 701. Using quantitative FC analysis, the percentage of IL-10⁺ (top panel) and the percentage of CD25^highFOXP3^high Treg (bottom panel) in T subsets were evaluated at indicated time intervals. Three independent experiments were done using T cells from 3 individuals. All results are shown as the percent means ± SDs. *P < .05; **P < .01; ***P < .001; ****P < .0001.