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Biology subjects

Dunbabin, P.

Publications and source records attributed to Dunbabin, P..

2 recordsLinked to original sources

Microdomes: Micro-engineered Microdome arrays enable standardised and shear-free 3D biology with full-spectrum optical imaging compatibility

Three-dimensional cellular models such as organoids and spheroids hold major promise for developmental biology, disease modelling and precision medicine, yet their large-scale production and analysis remain constrained by handling-induced shear stress, sample fragility, positional instability and limited compatibility with advanced imaging workflows. Here, we introduce Microdomes, dense arrays of open-top, dome-shaped microcavities. Each cavity holds a single specimen in its own miniature aquarium, accessed through a narrow apical opening that admits cells, medium, matrix and staining reagents while shielding it from the shear generated during routine pipetting. Each Microdomes chip accommodates more than 100 spheroids or organoids, supporting diverse cell types, co-culture formats and both matrix-free and matrix-embedded culture. All specimens are retained through prolonged culture, repeated medium exchange, fixation and immunostaining. Because every specimen occupies a fixed, addressable position against a thin transparent film, the same spheroid can be relocated and re-imaged over weeks of culture and across microscopes, from array-wide overviews to subcellular details, without transfer, embedding or other perturbation. Microdomes also support AI-based automated segmentation, from whole-spheroid outlines to individual nuclei in 3D, using common image analysis software. Microdomes thereby turn each array into a self-contained quality control unit, providing specimen-level traceability that organoid production pipelines currently lack.

cell biology↗

The way less obvious: PIEZO1 supports apoptotic cell extrusion by optimizing tissue mechanical tension for homeostasis.

Apical cell extrusion is a mechanical process that allows epithelia to eliminate apoptotic cells and prevent inflammation. Mechanosensitive ion channels are often invoked for their capacity to mediate rapid mechanical responses in dynamic morphogenetic processes. Here we report an unexpected strategy for PIEZO1 to support apoptotic extrusion. PIEZO1 inhibition blocks extrusion in cultured cells and zebrafish larvae. However, although PIEZO1 mediates calcium signals during the extrusion process, we show that extrusion is instead antagonized by increase in the preexisting mechanical tension of the epithelium when PIEZO1 is disrupted. Correcting enhanced pre-stress in PIEZO1-disrupted epithelia is sufficient to rescue apoptotic extrusion, even though it does not restore dynamic calcium signals. PIEZO1 supports mechanical homeostasis through a calcium/calcineurin-dependent pathway that protects MYPT1/myosin phosphatase from degradation to limit Myosin II activation. Therefore, PIEZO1 support the morphogenetic process of apoptotic extrusion through mechanical homeostasis.

cell biology↗