CD34 cell atlas of main organs implicates its impact on fibrosis.

Rationale: CD34 cells are believed being progenitors that may be used to treat cardiovascular disease. However, the exact identity and the role of CD34 cells in physiological and pathological conditions remain unclear.

Methods: We performed single-cell RNA sequencing analysis to provide a cell atlas of normal tissue/organ and pathological conditions. Furthermore, a genetic lineage tracing mouse model was used to investigate the role of CD34 cells in angiogenesis and organ fibrosis.

Results: Single-cell RNA sequencing analysis revealed a heterogeneous population of CD34 cells in both physiological and pathological conditions. Using a genetic lineage tracing mouse model, we showed that CD34 cells not only acquired endothelial cell fate involved in angiogenesis, but also, CD34 cells expressing Pi16 may transform into myofibroblast and thus participate in organ fibrosis.

Conclusion: A heterogeneous CD34 cells serve as a contributor not only to endothelial regeneration but also a wound healing response that may provide therapeutic insights into fibrosis.