Panel a shows flow cytometry plots measuring the ability of 19BBz-tEGFR and 19BBz-Rab5 CD8 positive CARTs to bind CD19 protein during the CAE assay. The x-axis represents the fluorescence intensity of PE-CD3, and the y-axis represents the count of cells. Panel b shows a line graph summarizing the data from Panel a, with the x-axis representing different time points during the CAE assay and the y-axis representing the percentage of CD8 positive CAR positive cells. Panel c shows flow cytometry plots for 19BBz-tEGFR, 19BBz-Rab5, and 19BBz-Rab5-S35N CARTs binding to CD19 protein during the CAE assay, with the same axes as Panel a. Panel d shows a line graph summarizing the data from Panel c, with the same axes as Panel b. Panel e shows flow cytometry plots for T cells transduced with 1928z-tEGFR or 1928z-Rab5 vectors binding to CD19 protein during the CAE assay, with the x-axis representing the fluorescence intensity of PE-CD3 and the y-axis representing the count of cells. Panel f shows a line graph summarizing the data from Panel e, with the same axes as Panel b. Panel g shows flow cytometry plots for T cells transduced with 1928z-tEGFR or 1928z-Rab5 vectors controlling tumor cells during the CAE assay, with the x-axis representing the fluorescence intensity of GFP-KL19 and the y-axis represents the count of cells. Panel h shows a line graph summarizing the data from Panel g, with the same axes as Panel b.
Rab5 expression maintains surface CARs on CARTs. (a and b) The ability of 19BBz-tEGFR and 19BBz-Rab5 CD8+ CARTs to bind CD19 protein shown by representative flow cytometry plots (a) and summary data (b) during the CAE assay. (c and d) The ability of 19BBz-tEGFR, 19BBz-Rab5, or 19BBz-Rab5-S35N CARTs to bind CD19 protein, shown by representative flow cytometry plots (c) and summary data (d) during the CAE assay. (e and f) The ability of T cells transduced with 1928z-tEGFR or 1928z-Rab5 vectors to bind CD19 protein was measured during the CAE assay by flow cytometry. (g and h) The ability of T cells transduced with 1928z-tEGFR or 1928z-Rab5 vectors to control tumor cells was measured during the CAE assay by flow cytometry. Data in a–h are representative of three independent experiments with samples from independent healthy donors.