Reihaneh Shafieian - Department of Anatomy and Cell Biology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
Maryam Moghaddam Matin - Department of Biology, Faculty of Sciences, Ferdowsi University of Mashhad, Mashhad, Iran
Amin Rahpeyma - Oral and Maxillofacial Diseases Research Center, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran
Alireza Fazel - Department of Anatomy and Cell Biology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
Hamideh Salari Sedigh - Department of Clinical Sciences, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran
Ariane Sadr-Nabavi - Department of Genetics, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
Halimeh Hassanzadeh - Department of Biology, Faculty of Sciences, Ferdowsi University of Mashhad, Mashhad, Iran
Alireza Ebrahimzadeh-Bideskan - Department of Anatomy and Cell Biology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran

Objective(s): Autologous bone transplantation known as the “gold standard” to reconstruction of osseous defects has known disadvantages. This study was designed to explore the effects of hydroxy-apatite/tricalcium-phosphate (HA/TCP) and platelet-rich plasma (PRP) on the osteogenesis ability of human adipose-derived mesenchymal stem cells (hAdMSCs) in vitro and in vivo. Materials and Methods: hAdMSCs were incubated with HA/TCP granules and/or PRP in vitro and then, cell proliferation and differentiation was assessed by MTT assay, AZR S staining and SEM examination. In vivo, four cylindrical defects were drilled in the mandibular bones of ۵ mongrel dogs and divided randomly into the following groups: I-autologous crushed bone, II- no filling material, III- HA/TCP and PRP, IV- PRP-enriched hAdMSCs seeded on HA/TCP granules. Inserted hAdMSCs were labeled to trace their contribution to bone tissue regeneration. Finally, cell tracing and tissue regeneration were evaluated by immunohistochemistry and histomorphometry methods, respectively.    Results: In vitro, co-incubation with HA/TCP granules significantly reduced proliferation and osteogenic differentiation ability of hAdMSCs; while PRP application promoted these capacities (P<۰.۰۵). In vivo, PRP-enriched hAdMSCs seeded on HA/TCP granules induced considerable bone formation in osseous defects (P<۰.۰۵). It was obviously shown that hAdMSCs were incorporated into the newly-formed bone.    Conclusion: Based on this study, application of stem cells could offer a helpful therapeutic tool in bone tissue regeneration. Although inserted hAdMSCs were identifiable throughout the newly-formed bone tissue, their few number could be an indicator of indirect role of hAdMSCs in tissue regeneration.

Adipose tissue, Bone, Dog, Osteogenesis, Stem cells, Tissue engineering