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Biology subjects

Okazaki, N.

Publications and source records attributed to Okazaki, N..

2 recordsLinked to original sources

Efficient generation of hematopoietic progenitor cells from human pluripotent stem cells by robotic automation

Differentiation of human pluripotent stem cells (hPSCs) into therapeutic cell types requires stringent control of developmental signals, but conventional manual operations introduce substantial intra- and inter-operator variability. While automation can reduce such variability, fixed systems often lack compatibility with the dynamic, stage-specific, and format-diverse manipulations required for hPSC culture and differentiation. Here, we establish a flexible robotic platform to standardize a stroma- and xeno-free embryoid body (EB)-based hematopoietic progenitor cell (HPC) differentiation process and integrate machine learning (ML) to optimize key process parameters including the concentrations of multiple signaling molecules. Despite intrinsic biological stochasticity and technical complexity associated with EB formation, the robotic platform substantially reduced experimental variation. ML-guided, unbiased exploration not only identified combinations of signaling inputs that markedly improved the efficiency and reproducibility of HPC differentiation and subsequent natural killer cell generation, but also illuminated key signaling logic underlying early human hematopoietic development. Together, these results demonstrate that data-driven robotic automation can uncover optimal culture conditions that are difficult to identify through conventional human-driven experimentation.

developmental biology↗

Hoxa10 mediates positional memory to govern stem cell function in adult skeletal muscle

Skeletal muscle stem cells (satellite cells) are distributed throughout the body with heterogeneous properties that corresponds to region-specific pathophysiology. However, topographical genes that have functions remain unidentified in satellite cells of adult muscle. Here, we showed that expression of Homeobox (Hox)-A cluster genes, key regulators of the embryonic body plan, was robustly maintained in both muscles and satellite cells in adult mice and humans, which recapitulates their embryonic origin. We observed that regionally specific expressed Hox genes were linked to hypermethylation of the Hox-A locus. We examined Hoxa10 inactivation in satellite cells and found it led to genomic instability and mitotic catastrophe, which resulted in a decline in the regionally specific regenerative ability of muscles in adult mice. Thus, our results showed that Hox gene expression profiles instill the embryonic history in satellite cells as positional memory, potentially modulating the region-specificity in adult skeletal muscles.

developmental biology↗