Role of Endothelial Differentiated Adipose-derived Stem Cells in Repairing Calvarial Critical Size Defects in the Laboratory Rat (Rattus norvegicus)
Final rept. 22 Jun 2011-16 Jul 2014
DAVID GRANT USAF MEDICAL CENTER TRAVIS AFB CA CLINICAL INVESTIGATION FACILITY
Pagination or Media Count:
Objectives Calvarial bone defects are amongst the most common combat injuries. The treatment of large defects is difficult due to donor site limitations. Our aim in this study was to evaluate in vivo bone engineering in poly lactic-co-glycolic acid PLGA scaffolds seeded with endothelial and osteogenic differentiated adipose-derived stem cells ASCs. Methods Rat ASCs were induced into endothelial ASC-endo and osteogenic ASC osteo lineages. The optimal duration of endothelial cell differentiation was evaluated with flow cytometry analysis. Osteogenic differentiation was confirmed with alizarin red staining. Critical size 8 mm defects were created in the calvaria of Lewis rats. The defects were treated with blank PLGA scaffolds group I, PLGA scaffolds with undifferentiated ASCs group II, PLGA scaffolds with ASC-osteo group III, or PLGA scaffolds with ASC-endo group IV. Bone healing in the defects with evaluated at 8 weeks postsurgery with micro-CT scans and histological staining with hematoxylin-eosin and Massons trichrome stains. Results Micro-CT analyses of calvarial defects showed the highest bone mineral density in the ASC-osteo group, but there was no statistically significant difference between treatments and control p 0.56. Photometric analysis of histology slides suggested a trend towards more bone formation in the ASC-osteo group, but there was no significant difference between treatments and control p 0.13. Conclusions We were able to successfully differentiate ASCs into endothelial and osteogenic lineages and confirmed this using gene expression, protein expression, and histology. PLGA scaffold was a suitable medium for cell seeding. However, we were unsuccessful in producing significant new bone formation when osteocyte or endothelial cell differentiated ASCs were seeded separately on scaffolds in rat critical sized calvarial defects.
- Medicine and Medical Research