Self-Assembling Hematopoietic Niche on a Chip: Bulk sequencing to investigate effect of proton radioablation

(Radiation Experiments: bulk sequencing data) Here we present an integrative, bottom-up approach towards emulating the human bone marrow in vitro. Our method harnesses the regenerative capacity of adult stem cells to self-assemble a complex, specialized microenvironment of human hematopoietic stem cells (HSCs) in a vascularized three-dimensional microphysiological system. Through flow cytometry and single-cell transcriptomic interrogation, we show that the microengineered niche can reconstitute HSC self-renewal, multilineage hematopoiesis, and complex ligand-receptor signaling pathways of the native human marrow. The ability of our model to generate functionally mature myeloid cells also makes it possible to mimic the key physiological processes of innate immunity including neutrophil chemotaxis and intravascular mobilization. To demonstrate the advanced application of the bone marrow-on-a-chip, we present i) a specialized model of bone marrow ablation by proton beam radiotherapy and ii) a multiorgan model of innate immune response against bacterial lung infection. This work advances our ability to reconstruct, probe, and deconvolve the complexity of the bone marrow niche, and may enable new capabilities to model human hematopoiesis and immunity for biomedical and pharmaceutical applications. Bone marrow hematopoietic niche models cultured in vitro were irradiated with 0 Gy, 0.2 Gy, 2 Gy, and 20 Gy of proton radiation, with each group comprising 3 independent biological replicates that were multiplexed.