The Prrx1eGFP Mouse Labels the Periosteum During Development and a Subpopulation of Osteogenic Periosteal Cells in the Adult

Brown, Sarah; Malik, Saif; Aljammal, Maria; O'Flynn, Aine; Hobbs, Carl; Shah, Mittal; Roberts, Scott J; Logan, Malcolm PO

Abstract

The identity of the cells that form the periosteum during development is controversial with current dogma suggesting these are derived from a Sox9-positive progenitor. Herein, we characterize a newly created Prrx1eGFP reporter transgenic mouse line during limb formation and postnatally. Interestingly, in the embryo Prrx1eGFP-labeled cells become restricted around the Sox9-positive cartilage anlage without themselves becoming Sox9-positive. In the adult, the Prrx1eGFP transgene live labels a subpopulation of cells within the periosteum that are enriched at specific sites, and this population is diminished in aged mice. The green fluorescent protein (GFP)-labeled subpopulation can be isolated using fluorescence-activated cell sorting (FACS) and represents approximately 8% of all isolated periosteal cells. The GFP-labeled subpopulation is significantly more osteogenic than unlabeled, GFP-negative periosteal cells. In addition, the osteogenic and chondrogenic capacity of periosteal cells in vitro can be extended with the addition of fibroblast growth factor (FGF) to the expansion media. We provide evidence to suggest that osteoblasts contributing to cortical bone formation in the embryo originate from Prrx1eGFP-positive cells within the perichondrium, which possibly piggyback on invading vascular cells and secrete new bone matrix. In summary, the Prrx1eGFP mouse is a powerful tool to visualize and isolate periosteal cells and to quantify their properties in the embryo and adult.

Citation

Brown, S., Malik, S., Aljammal, M., O'Flynn, A., Hobbs, C., Shah, M., …Logan, M. P. (in press). The Prrx1eGFP Mouse Labels the Periosteum During Development and a Subpopulation of Osteogenic Periosteal Cells in the Adult. JBMR Plus, e10707, https://doi.org/10.1002/jbm4.10707

• Journal Article Type: Article
• Acceptance Date: Nov 13, 2022
• Online Publication Date: Dec 14, 2022
• Deposit Date: Dec 15, 2022
• Publicly Available Date: Dec 19, 2022
• Journal: JBMR Plus
• Print ISSN: 2473-4039
• Electronic ISSN: 2473-4039
• Publisher: American Society for Bone and Mineral Research
• Peer Reviewed: Peer Reviewed
• Volume: e10707
• DOI: https://doi.org/10.1002/jbm4.10707
• Keywords: Orthopedics and Sports Medicine; Endocrinology, Diabetes and Metabolism
• Additional Information: Received: 2021-10-06; Accepted: 2022-11-13; Published: 2022-12-14