Perivascular Stem Cells Induce Bone formation and Vasculogenesis in Ectopic and Bone Injury Models
Aaron W James, Greg Chung, Greg Asatrian, Omar Velasco, Angel Pan, Alan Nguyen, Pei Liang, David Stoker, Kang Ting, Bruno Peault, Chia Soo. University of California, Los Angeles, CA
Background: Perivascular stem cells (PSCs) have recently been identified as phenotypically identical to mesenchymal stem cell (MSCs). This new insight has led to interest in the prospective identification of PSCs for the engineering of bone and soft tissue. Here, we describe the frequency of PSCs within adipose tissue, and the tissue morphology and functional outcomes after in vivo PSC application. Overall, we identify PSCs as a purified MSC population for bone tissue engineering.
Design: PSCs were obtained from human adipose tissue from than N>70 donors, based on expression of CD34 and CD146. PSCs were compared to an unsorted, patient-matched stromal population (stromal vascular fraction, SVF). Two methods were used to compare SVF to PSCs. First, an ectopic model of bone formation, using mouse intramuscular implantation. Second, rat posterolateral spine fusion was performed. Equivalent numbers of SVF or PSCs were used. In vivo analyses included micro CT, cell tracking, histology and immunohistochemistry (markers of osteogenesis, vasculogenesis, and proliferation), and biomechanical analyses.
Results: PSCs represent an abundant portion of adipose tissue (43% of SVF), with multilineage potential. In vivo, PSCs showed robust ectopic OPN+, OCN+ bone formation, and increased vasculogenesis. In a spinal fusion model, unsorted SVF did not induce fusion. In contrast, PSCs induced 80-100% fusion. This was accompanied by radiographic and histologic evidence of endochondral ossification.
Conclusions: PSCs are a newly recognized MSC population, harvestable from any vascularized organ. PSCs have robust osteogenic properties and hold promise for future efforts in skeletal tissue regeneration.
Category: Bone & Soft Tissue
Monday, March 4, 2013 9:30 AM
Poster Session I Stowell-Orbison/Surgical Pathology/Autopsy Awards Poster Session # 7, Monday Morning