Extended Data Fig. 1: Proteomic and flow cytometric analysis of CARs.

a, Volcano plots depicting fold change (log₂FC) and P value (-log₁₀ adjusted P value) for differentially phosphorylated peptides identified in CD19-CD28H/TM-4-1BBζ versus CD19-CD8H/TM-4-1BBζ at 0- and 90-minutes post-stimulation from two unique donors, as described in Fig. 1a. Differential peptide analyses were conducted using an empirical Bayes moderated T test, selected proteins with log₂FC ≥ 0.5, Benjamini-Hochberg adjusted P value ≤ 0.05 are labeled. Green indicates TCR proximal signaling proteins, blue indicates proteins interacting with the LAT signalosome and/or cytoskeleton, and magenta indicates distal signaling proteins and transcription factors. b, Flow cytometry data showing surface CD19-4-1BBζ CAR expression, and c, intracellular staining of proximal signaling molecules in T cells transduced as shown in Fig. 1c, representative of two independent experiments with different T cell donors.