Fig. 5: CD83 expression negatively affects CD8+ T-cell effector functions.

a–c Human T cells were retrovirally transduced with CD83 and weekly restimulated by K562-mOKT3/CD80. b Fold expansion of T cells. Arrows indicate T cell stimulation by K562-mOKT3/CD80 (n = 4 independent cultures, representative data of two experiments). c The frequency of CD83-transduced cells within the CD8⁺ T cell population was analyzed with flow cytometry after the 1st or 4th stimulation (n = 4 independent cultures). d, e Control or CD83-overexpressing T cells were analyzed for CFSE dilution upon the 4th restimulation. Representative flow cytometry plots (d) and the mean fluorescence intensity of CFSE 5 days after stimulation are shown (e), (n = 4 independent cultures). f, g Control or CD83-overexpressing anti-CD19 or anti-mesothelin CAR-T cells were analyzed for production of granzyme B and perforin and CD107a expression upon restimulation by NALM6 or K562-mesothelin. Representative flow cytometry plots for anti-mesothelin CAR-T cells (f) and mean fluorescence intensity are shown (g), (n = 3-4 independent cultures). h CD19-targeting CAR-T cells with or without ectopic expression of CD83 were analyzed for cytokine production upon restimulation by NALM6 (n = 3 independent cultures). i NSG mice subcutaneously transplanted with the mesothelin⁺ pancreatic cancer cell line AsPC-1 were treated by control or CD83-overexpressing CAR-T cells against mesothelin. CAR-T cells were cotransduced with the luciferase gene to monitor in vivo persistence. j, k Tumor volume was longitudinally monitored (n = 6 mice for each). l Total flux of the luciferase activity was analyzed by in vivo bioluminescent imaging (n = 6 mice, repeated measures one-way ANOVA with multiple comparison test for the log-transformed values). The data presented in (j–l) are a composite of three independent experiments. In (b, c, e, g, h, and k), statistical significance was analyzed by unpaired two-tailed t-test. NS not significant.