title: Human amniotic fluid stem cells seeded in fibroin scaffold produce in vivo mineralized matrix.
abstract: This study investigated the potential of amniotic fluid stem cells (AFSCs) to synthesize mineralized extracellular matrix (ECM) within different porous scaffolds of collagen, poly-D,L-lactic acid (PDLLA), and silk fibroin. The AFSCs were initially differentiated by using an osteogenic medium in two-dimensional culture, and expression of specific bone proteins and the physiologic mineral production by the AFSCs were analyzed. In particular, during differentiation process, AFSCs expressed proteins like Runt-related transcription factor 2 (Runx2), Osterix, Osteopontin, and Osteocalcin with a sequential expression, analogous to those occurring during osteoblast differentiation, and produced extracellular calcium stores. AFSCs were then cultured on three-dimensional (3D) scaffolds and evaluated for their ability to differentiate into osteoblastic cells in vivo. Stem cells were cultured in vitro for 1 week in collagen, fibroin, and PDLLA scaffolds. The effect of predifferentiation of the stem cells in scaffolds on the subsequent bone formation in vivo was determined in a rat subcutaneous model. With the addition of a third dimension, osteogenic differentiation and mineralized ECM production by AFSCs were significantly higher. This study demonstrated the strong potential of AFSCs to produce 3D mineralized bioengineered constructs in vivo and suggests that fibroin may be an effective scaffold material for functional repair of critical size bone defects.
authors.affiliation: Department of Laboratories, Pathological Anatomy and Forensic Medicine, University of Modena and Reggio Emilia, Modena, Italy. tullia.maraldi@unimore.it
authors.forename: Tullia
authors.initials: T
authors.lastname: Maraldi
authors.forename: Massimo
authors.initials: M
authors.lastname: Riccio
authors.forename: Elisa
authors.initials: E
authors.lastname: Resca
authors.forename: Alessandra
authors.initials: A
authors.lastname: Pisciotta
authors.forename: Giovanni B
authors.initials: GB
authors.lastname: La Sala
authors.forename: Adriano
authors.initials: A
authors.lastname: Ferrari
authors.forename: Giacomo
authors.initials: G
authors.lastname: Bruzzesi
authors.forename: Antonella
authors.initials: A
authors.lastname: Motta
authors.forename: Claudio
authors.initials: C
authors.lastname: Migliaresi
authors.forename: Laura
authors.initials: L
authors.lastname: Marzona
authors.forename: Anto
authors.initials: A
authors.lastname: De Pol
mesh_terms: D000653:Amniotic Fluid / Q000166:cytology*; D000818:Animals; D015153:Blotting, Western; D012831:Bombyx; D002454:Cell Differentiation / Q000502:physiology; D002478:Cells, Cultured; D003094:Collagen / Q000737:chemistry; D050659:Core Binding Factor Alpha 1 Subunit / Q000378:metabolism; D005349:Fibroins / Q000737:chemistry*; D005455:Fluorescent Antibody Technique; D006801:Humans; D018625:Microscopy, Atomic Force; D018613:Microscopy, Confocal; D015675:Osteocalcin / Q000378:metabolism; D010012:Osteogenesis / Q000502:physiology; D053495:Osteopontin / Q000378:metabolism; D047011:Silk / Q000737:chemistry*; D000076182:Sp7 Transcription Factor; D013234:Stem Cells / Q000166:cytology*; D054457:Tissue Scaffolds / Q000737:chemistry*; D014157:Transcription Factors / Q000378:metabolism
chemical_list: D050659:Core Binding Factor Alpha 1 Subunit; D047011:Silk; D000076182:Sp7 Transcription Factor; C478163:SP7 protein, human; D014157:Transcription Factors; D015675:Osteocalcin; D053495:Osteopontin; D003094:Collagen; D005349:Fibroins