Dissociable perfusion chip (DPC): perfusable microfluidic chip for single-cell screening of anti-cancer drugs in live glioblastoma explants

New approaches are needed to screen anti-cancer drugs that can target specific subpopulations of tumor cells. This study presents a microfluidic chip that enables parallel culture and drug perturbation of five thick tissue slices from human GBM resections, and removes the slices non-destructively for downstream single-cell RNA sequencing (scRNA-seq). Importantly, in contrast to methods relying on chemical attachment of tissue to chip, mechanical clamping of layers allows for positive-pressure perfusion of 3D slices and nondisruptive dissociation of tissue slices from the microfluidic chip. We ran the dissociable perfusion chip (DPC) on slice cultures freshly resected from human glioblastoma (within 1 h of surgery), one of the deadliest forms of malignant brain tumor which exhibits profound intra-tumoral heterogeneity that is challenging to recapitulate even with patient-derived models. DPC maintained similar fluidic conditions between channels and high cell viability in slices, and enabled downstream scRNA-seq to confirm that a topoisomerase inhibitor targets a subpopulation of proliferating tumor cells. Tissues run on DPC showed oxidative stress levels more similar to uncultured GBM slices compared to Transwell culture, as demonstrated by scRNA-seq, fluorometric assessment on a separate human patient sample, and assessment of long-term viability in mouse GBM samples under low and high oxygen tension. Overall, this proof-of-concept work suggests that combining DPC with off-chip scRNA-seq enables rapid, high-resolution identification of cell type-specific drug responses directly in GBM tissue from individual patients. Future work will aim to use this approach for screening of multiple drugs and further validation on additional fresh human GBM slices.