Figure 6.

Spacer and transmembrane optimization endow DC CIK cells of higher selectivity toward double-positive CD33/CD123 cells. (A) DC vector scheme. Bicistronic DC IL-3z/CD33 CCR carrying different spacers and transmembrane domains. (B-C), Immune synapse-binding avidity of NT and DC WT CIK cells to OCI-AML3 WT, OCI-AML3 CD33⁻, and OCI-AML3 CD123⁻/CD33⁻ targets assessed via acoustic force microfluidic microscopy. Data represent mean ± SD and combined experiments from 2 separate donors. (D-E), Long-term (E:T ratio of 1:10) cytotoxicity against KG-1 cell line. Percentage of residual KG-1 cells after the 1-week coculture (D) and CD3 fold change after the 1-week coculture (E). Mean ± SEM from independent CIK cell donors is shown (n = 3 for all the conditions except for n = 1 against CD123⁻/CD33⁺ KG-1 cells). (F) Kaplan-Meier curves of overall survival. P value indicates comparison between the KG-1 only cohort and the DC CIK-treated cohorts. ns, not significant (P value >.05), ∗P value <.05. (G) Representative dot plot of PB analysis. (H) Analysis of hCD45⁺/CD33⁺/CD123⁺ cells in the PB of untreated and treated mice. (I) Analysis of hCD45⁺/CD3⁺ cells in the PB of DC CIK cell–treated mice. Paired comparisons were performed using the Tukey test and adjusted for multiple comparisons in panels D-E. ns, not significant (P value >.05); ∗P value <.05, ∗∗P value <.01, ∗∗∗P value <.001. SEM, standard error of the mean.