Dermal fibroblasts are transcriptomically heterogeneous. In spite of numerous single-cell RNA sequencing (scRNAseq) studies dedicated to decipher fibroblast heterogeneity, previous approaches lack sufficient insight and do not establish a bridge between mouse and human fibroblasts data. We aimed to obtain a comprehensive map of human and mouseskin fibroblasts from pre-existing data. To this end, 30 independent scRNAseq datasets (22 including human dermal fibroblasts and 8 from mouse skin) were subjected to a customized computational pipeline to obtain robust cell subpopulations that were constant across datasets, alongside their marker genes. In this analysis, we defined a total of 15 populations divided into 5 main axes (A-E) in human datasets, and 17 populations divided into 5 main axes (a-e) in mouse datasets. Interestingly, most of these cell clusters were consistent, meaning that they appeared throughout most of the datasets, with no meaningful cell population remaining unlabelled. Further, the comparison of human and mouse fibroblast subpopulations reveals that, despite the intrinsic differences between rodent and human skin, in many cases a one-to-one correspondence between species may be found with a partial overlap in the cell cluster-defining markers, perhaps suggesting comparable functionsof particular cell subpopulations across species. Thereby, we were able to capture into discrete populations the heterogeneity of the mouse and human dermal fibroblasts, using specific markers. This atlas is a useful tool for establishing a detailed annotation of the human and mouse dermal fibroblast subpopulations, as well as for deepening in the specific functions of each fibroblast subtype with the advantage of providing tools for cross-species comparisons.

ESDR555 - Dermal single-cell atlas: a novel tool to explore fibroblast heterogeneity

The scientific meeting of the European Society for Dermatological Research (ESDR) is held yearly, usually in September. With an international attendance of more than 1000 skin scientists from around the globe, the four-day event includes short oral presentations from peer-reviewed abstracts, keynote lectures from international experts, sponsored symposia, satellite programs, educational events as well as an important focus on posters, networking and building collaborations amongst scientists. For more information about this year’s meeting visit our website.