Microfluidic single-cell drug screening: toward personalized precision therapy in chronic myeloid leukemia.

Chronic myeloid leukemia (CML) treatment employs several FDA-approved BCR::ABL1 tyrosine kinase inhibitors (TKIs) with distinct efficacy and side effects influenced by patient-specific factors. This study introduces a microfluidic cell culture array for the comparative analysis of six BCR::ABL1 TKIs, namely imatinib, nilotinib, bosutinib, ponatinib, dasatinib, and asciminib, using CML-related cell lines. The device provides a continuous, chemostat-like microfluidic environment that enables quantitative drug sensitivity scoring. The microchambers for cell culture notably offer advantages for single-cell imaging of suspension leukemia cells, which tend to aggregate in conventional culture platforms. This system supports the detailed characterization of cell viability across various TKI types and concentrations, yielding comprehensive mathematical metrics to assess relative drug efficacy. In this study, we compared drug responses in K562 and Ba/F3 BCR::ABL1 cell lines, including the T315I mutant variant, and specifically demonstrated that Ba/F3 cells harboring the T315I mutation exhibit resistance to the first- and second-generation TKIs, responding only to ponatinib and asciminib. We further validated the device with a CML patient-derived bone marrow sample, requiring only minimal adjustments to the experimental conditions. The proposed microfluidic single-cell-based screening array could refine treatment regimens and advance personalized medicine in CML.