gms | German Medical Science

Objectives/Interrogation: Fibrosis is a major cause of morbidity and mortality. However, despite intense research efforts little progress has been made in clinical treatment across several diseases. In all forms of fibrosis, myofibroblasts are the key effector cell and drive pathogenesis through the secretion and remodeling of excess matrix proteins. We study Dupuytren's disease, a common fibrotic condition of the hand, as it provides an excellent human model to investigate mechanism behind fibrotic disease. This condition provides an abundant supply of primary human fibrotic tissue at a relatively early stage and through two distinct structures allows us to map and compare the early myofibroblast rich and later matrix rich stages of fibrosis.

Methods: We have completed a large scale single cell RNA-seq of Dupuytren's disease and built a molecular census of the complex cellular ecosystem in fibrosis. In addition, we have validated our gene expression data at the protein level using immunohistochemistry and flow cytomtery. Moreover, through a novel live cell imaging assay we have quantified the force profiles of distinct stromal cell subsets.

Results and Conclusions: We have uncovered the molecular signatures of fibroblasts and myofibroblast and report novel gene markers of distinct stromal cell populations. Moreover, by integrating bulk and single cell transcriptome profiling we elucidate how the fibrotic microenvironment may influence stromal cell phenotypes. Finally, novel stromal cell populations have been interrogated with traction force microscopy, a live cell imaging assay that enables the dissection of mechanical force at single cell resolution. This has provided a unique lens into the biophysical signature of novel stromal cells in fibrotic disease.

This study is the first ever single cell RNA-seq of a human fibrotic disorder and provides a new perspective on musculoskeletal disease.