Search bioRxiv⌕ Search

Biology subjects

Levron, C. L.

Publications and source records attributed to Levron, C. L..

2 recordsLinked to original sources

Lifelong tissue memory relies on spatially organised dedicated progenitors located distally from the injury

It is believed epithelial cells that have participated in a wound repair elicit a more efficient but locally restricted response to future injuries. However here we show that the cell adaptation resulting from a localised tissue damage has a wide spatial impact at a scale not previously noticed. We demonstrate that away from injured site, after a first injury a specific epithelial stem cell population gives rise to long term wound-memory progenitors residing in their own niche of origin. Notably these progenitors have not taken part in the first wound healing but become pre-activated through priming. This adaptation differs from classical features of trained immunity previously shown to be adopted by other epithelial stem cells. Our newly identified wound-distal memory cells display a cell-autonomous transcriptional pre-activated state leading to an enhanced wound repair ability that can be partially recapitulated through epigenetic perturbation even in absence of an injury. Importantly, the harmful consequences of wound repair, such as exacerbated tumorigenesis, occur within these primed cells and follow their spatial distribution. Overall, we show that sub-organ scale adaptation of an injury relies on spatially organised and memory-dedicated progenitors, characterised by an epigenetic actionable cell state, that predisposes to tumour onset.

cell biology↗

Molecular and spatial design of early skin development

A wealth of specialized cell populations within the skin facilitates its hair producing, protective, sensory and thermoregulatory functions, but how the vast cell-type diversity and tissue architecture develops is largely unexplored. Here, with single-cell transcriptomics, spatial cell-type assignment and cell-lineage tracing we deconstruct early embryonic mouse skin during the key transitions from seemingly uniform developmental precursor states to a multilayered, multilineage epithelium and complex dermal identity. We reveal the spatiotemporal emergence of hair-follicle-inducing, muscle-supportive, and fascia-forming fibroblasts. We also uncover the formation of the panniculus carnosus muscle, sprouting blood vessels without pericyte coverage, and the earliest residence of mast and dendritic immune cells in skin. Finally, we reveal an unexpected epithelial heterogeneity within the early single-layered epidermis and a signaling-rich periderm layer. Overall, this cellular blueprint of early skin development establishes histological landmarks - essential for placing cells in their spatial tissue context - and highlights unprecedented dynamical interactions among skin cells.

developmental biology↗