Extended Data Fig. 7: In vivo trogocytosis was associated with poor viability of CAR-NK cells.
From: KIR-based inhibitory CARs overcome CAR-NK cell trogocytosis-mediated fratricide and tumor escape
(a) Schematic illustration of the timeline using a mouse model of lymphoma, engrafted with 0.2×105 luc/GFP−expressing CD19+ Raji cells and treated with a single infusion of CAR19-NK cells or NT-NK cells as control. Blood, BM, spleen and liver were harvested for analysis at two weeks (day 13-15), three to four weeks (day 20-27), or at the end time point (day 29-34) after infusion. (b) Tumor burden was assessed weekly by BLI. The BLI intensity is shown for each mouse after infusion with CAR-NK cells (green) or NT-NK cells (blue). Untreated mice were used as controls (black). (c) Heatmap showing expression levels of phenotypic and functional markers on fractions of TROG+ (tCD19+) and TROG− live hCD45+GFP−CD56+CD3−NK cells at different timepoints post-infusion. The expression level for each marker is represented by the color grey (low) - orange (high) and the size. (d) The phenotypic cell signature for each condition was evaluated by mass cytometry and merged to create a single t-SNE map. Expression of tCD19 (orange) and CAR19 (green) on hCD45+GFP-CD56+CD3- NK cells was determined based on their expression on NT-NK cell controls. (e) Violin plots showing expression of tCD19 on NK cells within each cluster harvested from mice treated with CAR19-NK cells (left); cisplatin levels within the TROG+ vs. TROG− fractions for each cluster (right) are shown. (f) Violin plots showing expression of tCD19 on NT-NK cells within each cluster (left); cisplatin levels within the TROG+ vs. TROG− fractions for each cluster (right) are shown. (g) Gene signature for total hCD45+ cells at different time points during the treatment course. The t-SNE maps, generated with the Seurat package in R, show color-coded expression levels for CD19 and MS4A1 (Raji cells), NKG7 and FCGR3A (NK cells) for each cluster. P values were determined by two-tailed Wilcoxon matched pairs test in panels e and f. Data were assessed by mass cytometry and shown in violin graph with the indicated median.
