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Kumamoto, J.

Publications and source records attributed to Kumamoto, J..

3 recordsLinked to original sources

Spatial confinement induces reciprocating migration of epidermal keratinocytes and forms triphasic epithelia

Epithelial cells undergo epithelial-mesenchymal transition (EMT) during migration and regain their epithelial phenotype in the post-migration phase (mesenchymal-epithelial transition; MET). We established an experimental system that reproduces a three-compartment epithelial structure comprising the original epithelium, its EMT state, and its MET state. Keratinocytes (KCs), skin epithelial cells, placed on a microporous membrane migrated through 3.0-{micro}m or larger micropores. The 3.0-{micro}m-pored membrane induced an epithelial structure with three distinct states: stratified KCs above the membrane, KCs showing EMT within the micropores, and a new stratified epithelium under the membrane. The membrane with larger micropores failed to maintain the three-compartment epithelial structure. Live imaging revealed that KCs moved in an oscillatory manner, with actin-rich filopodia-like structures extending into and out of the 3.0-{micro}m micropores, while the cells migrated unidirectionally into larger micropores. Piezo1 and keratin 6 were identified as negative modulators of KC entry into and exit from the 3.0-{micro}m micropores. These results demonstrate that non-cancerous epithelial cells migrate through confined spaces in an oscillatory manner, which might contribute to the formation of a three-compartment epithelial structure that recapitulates key aspects of wound healing.

cell biology↗

Harnessing Synaptic Vesicle Release and Recycling Mechanism for Molecule Delivery to Neurons

Neurodegenerative clinical trials often fail due to insufficient drug doses in reaching targeted cells and the unintended delivery to non-targeted cells. This study demonstrates an alternative neuron-selective drug delivery system, which utilizes the synaptic vesicle release and recycling mechanism (SVRM) by antibody shuttles targeting synaptic vesicle transmembrane proteins for molecule delivery. Using Synaptotagmin-2 (SYT2), we exemplify that intravenously administered anti-SYT2 antibodies localize to neuromuscular junctions, undergo uptake, and retrograde transport to ChAT-positive motor neurons (MNs) in the spinal cord and brainstem. The delivery of anti-microtubule agent and Malat1 gapmer antisense oligonucleotide to MNs with anti-SYT2 antibodies induces axon degeneration and reduction of Malat1 RNA expression, respectively. This approach circumvents the blood-spinal cord barrier, enabling selective delivery of therapeutic molecules to neurons while minimizing effects in non-targeted cells. Thus harnessing SVRM presents a promising strategy for enhancing drug concentrations in neurons and improving treatment efficacy for neurodegenerative diseases.

neuroscience↗

Cell-cell adhesion drives patterning in stratified epithelia

Epithelia consist of proliferating and differentiating cells that often display patterned arrangements. However, the mechanism regulating these spatial arrangements remains unclear. Here, we show that cell-cell adhesion dictates multicellular patterning in stratified epithelia. When cultured keratinocytes, a type of epithelial cell in the skin, are subjected to starvation, they spontaneously develop a pattern characterized by areas of high and low cell density. Pharmacological and knockout experiments show that adherens junctions are essential for patterning, whereas mathematical modeling indicates that cell-cell adhesion alone is sufficient to form regions with high/low cell density. This phenomenon, called cell-cell adhesion-induced patterning (CAIP), influences cell differentiation and proliferation through Yes-associated protein modulation. Starvation, which induces CAIP, enhances the stratification of the epithelia. These findings highlight the intrinsic self-organizing property of epithelial cells and indicate that CAIP modulation might promote wound healing in clinical settings.

cell biology↗