Repair of Rat Mandibular Bone Defects by Alveolar Osteoblasts in a Novel Plasma-Derived Albumin Scaffold

Abstract

Repair of bone deficiencies in the craniofacial skeleton remains a difficult clinical problem. The aim of this study was to evaluate a novel albumin scaffold seeded with human alveolar osteoblasts and implanted into experimental mandibular defects. An experimental solid protein scaffold was prepared with human plasmatic albumin crossed with a glutaraldehyde-type agent. Microstructure of scaffold and mechanical properties were examined using scanning electron microscopy and a stress-controlled rheometer. Bilateral critical mandibular defects were created in eight immunodeficient rats. Defects of the right side of the mandibles received the cell-scaffold construct in all animals. All left mandibular defects were left untreated as blank controls. Sections of the defects were collected at 5, 8, and 11 weeks postsurgery and processed for histological and immunohistochemical observation, computed tomography examination, and computed tomography digital analysis. Histologically, bone formation was observed in both groups at 5 weeks postsurgery, and the engineered bone became more mature after 8 and 11 weeks, which was similar to normal bone. The origin of bone-forming cells within the defects and the localization of implanted human osteoblasts were confirmed by human vimentin expression. No bone formation could be observed at any control defect. Bone density after 8 weeks was significantly higher than that of the 5-week group (p = 0.02), and significant differences were also observed between 8 and 11 weeks (p< 0.01). The results indicate the clinical feasibility of albumin scaffold loaded with human alveolar cells and that it can be used as a good alternative for bone regeneration.

Collagen I gel promotes homogenous osteogenic differentiation of adipose tissue-derived mesenchymal stem cells in serum-derived albumin scaffold

“…Because bone is always under continuous stress, the mechanical properties of the construct implanted into bone are essential for the repair of bone defects. This scaffold has been proven to provide an appropriate mechanical strength for bone reconstruction in a previous study [14]. A porous structure is also a very important element of scaffolds for bone tissue engineering.…”

“…In addition, the easy and inexpensive production of this scaffold makes it more suitable for the repair of bone defects than the previous artificial scaffold materials. Different types of cells have been used for bone tissue engineering, including bone marrow cells, periosteal cells, osteoblasts derived directly from bone, and MSCs derived from various tissues [5,14,15,21]. Ideal cells seeded for bone engineering should be able to proliferate quickly, function like osteoblast, be non-immunologic when implanted in vivo, and be biocompatible with scaffold materials [2,22].…”

“…Ideal cells seeded for bone engineering should be able to proliferate quickly, function like osteoblast, be non-immunologic when implanted in vivo, and be biocompatible with scaffold materials [2,22]. Previous studies have shown that human alveolar osteoblasts cultured in the serum-derived albumin scaffold enhance bone formation in ectopic and orthotopic implantations [14,15]. However, harvesting of bone marrow or osteoblasts is a painful and laborious process, and the number and differentiation potential of cells decrease with increasing age of the donor [23].…”

“…Serum-derived albumin scaffolds were fabricated according to the freeze-drying and chemical cross-linking procedures [14,15]. Briefly, 10 ml of canine venous blood was taken by venipuncture and was kept at 37°C for 30 min to retract fibrin clots.…”

Human Bone Xenografts: from Preclinical Testing for Regenerative Medicine to Modeling of Diseases

“…About 7 % (13 out of 175) of the studies showed little healing after the treatment with cellular scaffolds, with compromised efficacy ascribed to inappropriate choice of cells or scaffolds, poor conditions, or insufficient amount of cells. Notably, in eight studies using osteoblast cell sources, four showed no improvement to the healing, with two showing positive results only when BMP-2-transduced cell lines were used [35][36][37][38][39][40][41][42].…”