Immunotherapy-resistant acute lymphoblastic leukemia cells exhibit reduced CD19 and CD22 expression and BTK pathway dependency

While therapies targeting CD19 by antibodies, CAR-T cells and T cell engagers have improved theresponse rates in B-cell malignancies; the emergence of resistant cell populations with low CD19expression can lead to relapsed disease. Single-cell (sc) RNAseq showed increase in transcriptionally distinct CD19low populations in resistant cells.