Figure 4.

GD3 CAR Tregs provide melanocytes with superior protection from T cell-mediated cytotoxicity in vitro. The immunosuppressive ability of GD3 CAR Tregs and untransduced Tregs was compared in vitro. (A) Viability of HLA-A2⁺ human melanocytes (targets) in the presence or absence of murine Teffs and Tregs (1:10:1) is represented over time. Representative images of (B) HLA-A2⁺ human melanocytes (C) combined with murine Teffs, and additionally with (D) murine untransduced Tregs, or (E) GD3 CAR Tregs. Dead cells are marked by a red precipitate formed by caspase activity. Statistical significance was determined by two-way ANOVA with aligned rank transformation followed by Tukey’s pairwise multiple comparisons test. *p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001 (Scale bar = 50μm).