Extended Data Fig. 7: ΔFAS enhances the competitive fitness of CAR-T cells following repetitive tumor cell exposure in a FASLG-dependent manner across donors and cancer types.
From: CAR-engineered lymphocyte persistence is governed by a FAS ligand–FAS autoregulatory circuit
(a,b) Relative antigen-driven in vitro expansion of control and FASLG KO 1928ζ CAR-T cells ± ΔFAS coexpression following repetitive exposure to different hematologic malignancies. (a) CAR-T cells derived from donor 20240412 A that express (tEGFR+) or do not express (tLNGFR+) ΔFAS were combined in ~1:1 ratio on day 0 and serially restimulated at indicated time points with K562-CD19 FASLG KO leukemia cells (left panel) or left unstimulated as controls (right panel). (b) Same as (a) but CAR-T cells were generated from donor 20240518 A and restimulated with wild-type (WT) Nalm6 leukemia cells. (c,d) Relative antigen-driven in vitro expansion of control versus FASLG KO (PSMA)28ζ or (MSLN)28ζ CAR-T cells ± ΔFAS coexpression following repetitive exposure to different solid malignancies. (c) (PSMA)28ζ CAR-T cells that express (tEGFR+) or do not express (tLNGFR+) ΔFAS were combined in ~1:1 ratio on day 0 and serially restimulated at indicated time points with PC3-PSMA (left panel), a human prostate cancer cell line PC3 transduced with PSMA, or left unstimulated as controls (right panel). (d) Same as (c) but using a (MSLN)28ζ CAR serially restimulated with AsPC1, a human pancreatic cancer cell line that naturally expresses mesothelin. Data in all panels reflect the ratio of tEGFR/tLNGFR T cells measured by FACS at indicated time points and is displayed as the mean ratio ± s.e.m. (n = 3 biologically independent samples). Groups were compared using a paired two-tailed Student’s t-test for accumulated differences between each time point. ns, not significant (P > 0.05).
