7/7 Our data suggest that in a reversible fibrosis model, sCap are recruited and can act as progenitor cells to reconstitute the gCap pool to regenerate the integrity of the alveolar endothelial capillaries while aging appears to delay this process. 🙏 to our supports @agencerecherche.bsky.social

6/7 We also found that aging altered the transcriptome of gCap in control mice, with a signature suggestive of a pro-fibrotic and pro-inflammatory state, that may participate in the dysfunction of other cells in the alveolar niche and impede alveolar regeneration.

5/7 RNA velocity approach indicated that following lung injury, sCap are recruited and may function as progenitor cells that can initiate a differentiation process, transiting through Lrg1+ gCap before reaching the physiological gCap cell state.

4/7 These systemic EC corresponds to two distinct populations: one with venous macrovascular origin previously defined as SV EC and a second one lacking typical macrovascular and venous markers, corresponding to systemic capillary EC (sCap), in agreement with a recent study in COVID patients.

3/7 .. we identified aging-associated changes in PCEC pops, including aCap and gCap, shifting towards a pro-angiogenic phenotype expressing Lrg1 and associated with alveolar niche regeneration, as well as the emergence of homologous Col15a1-positive systemic EC previously identified in IPF

2/7 Using scRNA-seq and spatial transcriptomics, we present a whole picture of cell dynamic changes in young and aged lungs during fibrosis formation and resolution at 3 time points. Focusing on transcriptomic alterations correlated with a delayed fibrosis resolution in aged mice...

👏 again to Arun Lingampally @jlugiessen.bsky.social and Marin truchi @univcotedazur.bsky.social @cnrsbiologie.bsky.social and all collaborators and supports! @agencerecherche.bsky.social

The follow-up has just been released in Aging Cell dealing with the impact of aging on differentiation trajectories in the MYF to LIF switch: onlinelibrary.wiley.com/doi/10.1111/...

With a nice editorial “Tracing the origins of fibrotic fibroblasts: does the name matter? Look at the genes!” publications.ersnet.org/content/erj/...

Great work, congrats to all the team 👏