CD105⁺CD90⁺CD13⁺ identifies a clonogenic subset of adventitial lung fibroblasts

Mesenchymal cells are important components of specified niches in the lung, and can mediate a wide range of processes including tissue regeneration and repair. Dysregulation of these processes can lead to improper remodeling of tissue as observed in several lung diseases. The mesenchymal cells responsible remain poorly described, partially due to the heterogenic nature of the mesenchymal compartment and the absence of appropriate markers. Here, we describe that CD105⁺CD90⁺ mesenchymal cells can be divided into two populations based on their expression of CD13/aminopeptidase N (CD105⁺CD90⁺CD13^- and CD105⁺CD90⁺CD13⁺). By prospective isolation using FACS, we show that both these populations give rise to clonogenic fibroblast-like cells, but with an increased clonogenic and proliferative capacity of CD105⁺CD90⁺CD13⁺ cells. Transcriptomic and spatial analysis pinpoints an adventitial fibroblast subset as the origin of CD105⁺CD90⁺CD13⁺ clonogenic mesenchymal cells in human lung.