Fig. 1: FASLG is expressed by endogenous and CAR-expressing lymphocytes.
From: CAR-engineered lymphocyte persistence is governed by a FAS ligand–FAS autoregulatory circuit
a, UMAP visualization of scRNA-seq from n = 244,809 immune and nonimmune cells obtained from the tumor and peripheral blood of patients with n = 10 hematologic cancers, n = 27 solid cancers and peripheral blood from n = 4 healthy donors. Each dot represents an individual cell assigned to one of 18 inferred cell types. CLL, chronic lymphocytic leukemia; Mono, monocyte; MP, macrophage; DC, dendritic cell; Treg, regulatory T cell; Tcon, conventional T cell; Tprolif, proliferating T cell. b, Log-transformed normalized gene expression values for FAS and FASLG overlaid on the UMAP coordinates defined in a. c, Comparison of the frequency and magnitude of FAS and FASLG expression by individual cells assigned to each inferred cell type identified in the UMAP. Bubble size represents the frequency of each cell type that expresses the indicated gene and color indicates the relative intensity of expression. d,e, Representative immunofluorescent confocal image (d) and summary violin plots (e) quantifying FASLG mRNA expression by endogenous and CAR-expressing T cells in the bone marrow of patients with B-ALL treated with a 1928ζ CAR. Samples were co-hybridized with DAPI (blue) and multiplexed RNA-FISH probes specific for the mRNA sequence of the CAR’s single-chain variable fragment (scFv) (green), CD3E mRNA (white) and FASLG mRNA (red). Data are derived from 52 annotated regions using samples from n = 3 patients. Violin distributions are centered around the median (red horizontal line) with quartiles ranges displayed above and below (dashed horizontal lines). The maxima and minima are represented by the top and bottom of each plot. Each dot represents mean FASLG mRNA expression within a particular cell type from an annotated region of interest. f, Summary scatter-plot demonstrating the frequency of FASLG+ T cells which either coexpress or do not express a 1928ζ CAR transgene in n = 16 patients with diffuse large B cell lymphoma (DLBC) measured using scRNA-seq. Each dot represents an individual patient. All P values were calculated using a two-sided Student’s t-test. a.u., arbitrary fluorescence units.
