Bone Regeneration with Autologous Plasma, Bone Marrow Stromal Cells, and Porous β-Tricalcium Phosphate in Nonhuman Primates

Advantages of creation of holes and removal of air in artificial bone for early bone formation when used artificial bone as a gap filler in open wedge high tibial osteotomy

Recently, many facilities perform open wedge high tibial osteotomy (OWHTO) using artificial bone as a gap filler. However, there are many cases in which artificial bone is used without a clear purpose. We recommend a surgical technique to promote early synostosis between artificial bone and recipient bone due to mechanical support especially in the early stage after OWHTO. At our hospital, beta-tricalcium phosphate (β-TCP) with 60% porosity is used in OWHTO. Initially, a wedge-shaped block-type β-TCP, as large as possible, was inserted into the gap. However, from the standpoint of initial mechanical support, we changed the artificial bone size and created intentional holes. Furthermore, we removed air bubbles from β-TCP. We evaluated the synostosis on the basis of clinical results and diagnostic imaging. As a result of creating holes and removing air from the artificial bone, a trend toward faster synostosis was noted, especially at the early stage. No adverse events such as tibial plateau fracture, lateral cortical fracture, plate and screw failure and correction loss due to reducing the size of the artificial bone occurred, but placement of the artificial bone in contact with cortical bone and surface contact installation with the recipient bone tissue was important. When using artificial bone in OWHTO, holes formation and removal of air from the artificial bone are recommended for faster synostosis between artificial bone and recipient bone in the early stage after surgery. Artificial bone should be used, with attention to its positioning and shape, for efficient mechanical support.

Incorporation of Fucoidan in β-Tricalcium phosphate-Chitosan scaffold prompts the differentiation of human bone marrow stromal cells into osteogenic lineage

In our previous study, we reported the fabrication and characterization of a novel tricalcium phosphate-fucoidan-chitosan (TCP-Fu-Ch) biocomposite scaffold. However, the previous report did not show whether the biocomposite scaffold can exhibit osteogenic differentiation of human bone marrow stromal cells in osteogenic media and normal media supplemented with platelet-derived growth factor (PDGF-BB). On day 15, the release of osteocalcin, was significant in the TCP-Fu-Ch scaffold, when compared with that in the TCP-Ch scaffold, and the level of release was approximately 8 and 6 ng/ml in osteogenic and normal media supplemented with PDGF-BB, respectively. Scanning electron microscopy of the TCP-Fu-Ch scaffold demonstrated mineralization and apatite layer formation on day 14, while the addition of PDGF-BB also improved the osteogenic differentiation of the scaffold. An array of gene expression analysis demonstrated that TCP-Fu-Ch scaffold cultured in osteogenic and normal media supplemented with PDGF-BB showed significant improvement in the expression of collagen 1, Runt-related transcription factor 2, osteonectin, bone gamma-carboxyglutamate protein, alkaline phosphatase, and PPA2, but a decline in the expression of integrin. Altogether, the present study demonstrated that fucoidan-incorporated TCP-Ch scaffold could be used in the differentiation of bone marrow stromal cells and can be a potential candidate for the treatment of bone-related ailments through tissue engineering technology.

Bone Defect Regeneration by a Combination of a β-Tricalcium Phosphate Scaffold and Bone Marrow Stromal Cells in a Non-Human Primate Model

Background:

Reconstruction of large bone defects is a great challenge in orthopedic research. In the present study, we prepared composites of bone marrow-derived stromal cells (BMSCs) and β-tricalcium phosphate (β-TCP) with three novel aspects: proliferation of BMSCs with continuous dexamethasone treatment, cell loading under low pressure, and use of autologous plasma as the cell loading medium. The effectiveness of the resulting composite for large bone-defect reconstruction was tested in a non-human primate model, and the bone union capability of the regenerated bones was examined.

Materials and Methods:

Primary surgery: Bone defects (5 cm long) were created in the left femurs of nine cynomolgus monkeys with resection of the periosteum (five cases) or without resection (four cases), and porous β-TCP blocks were transplanted into the defects. Secondary surgery: Bone marrow aspirates harvested from seven of the nine monkeys were cultured with dexamethasone, and BMSCs were obtained. BMSCs were suspended in autologous plasma and introduced into a porous β-TCP block under low-pressure conditions. The BMSC/β-TCP composites were transplanted into bone defects created at the same sites as the primary surgery. Bone union evaluation: Five regenerated femurs were shortened by osteotomy surgery 8 to 15 months after transplantation of the β-TCP/BMSC composites, and bone union was evaluated radiographically.

Results:

After the primary surgery and treatment with β-TCP alone, one of the five periosteum-resected monkeys and two of the four periosteum-preserved monkeys exhibited successful bone reconstruction. In contrast, five of the seven cases treated with the β-TCP/MSC composite showed successful bone regeneration. In four of the five osteotomy cases, bone union was confirmed.

Conclusion:

We validated the effectiveness of a novel β-TCP/BMSC composite for large bone defect regeneration and confirmed the bone union capability of the regenerated bone.

Posterolateral spinal fusion with ostegenesis induced BMSC seeded TCP/HA in a sheep model

Autogenous bone graft is the gold standard for fusion procedure. However, pain at donor site and inconsistent outcome have left a surgeon to venture into some other technique for spinal fusion. The objective of this study was to determine whether osteogenesis induced bone marrow stem cells with the combination of ceramics granules (HA or TCP/HA), and fibrin could serve as an alternative to generate spinal fusion. The sheep's bone marrow mesenchymal stem cells (BMSCs) were aspirated form iliac crest and cultured for several passages until confluence. BMSCs were trypsinized and seeded on hydroxyapatite scaffold (HA) and tricalcium phosphate/hydroxyapatite (TCP/HA) for further osteogenic differentiation in the osteogenic medium one week before implantation. Six adult sheep underwent three-level, bilateral, posterolateral intertransverse process fusions at L1-L6. Three fusion sites in each animal were assigned to three treatments: (a) HA constructs group/L1-L2, (b) TCP/HA constructs group/L2-L3, and (c) autogenous bone graft group/L5-L6. The spinal fusion segments were evaluated using radiography, manual palpation, histological analysis and scanning electron microscopy (SEM) 12 weeks post implantation. The TCP/HA constructs achieved superior lumbar intertransverse fusion compared to HA construct but autogenous bone graft still produced the best fusion among all.

Reliability and validity of the Swedish version of the Scoliosis Research Society-22 (SRS-22r) patient questionnaire for idiopathic scoliosis

STUDY DESIGN

Two quality-of-life questionnaires were completed, once or twice, by patients with idiopathic scoliosis from 3 centers for scoliosis care in Sweden. These patients were under observation, during brace treatment, or after treatment with either a brace or surgery.

OBJECTIVE

The aim of the study was to translate and validate the revised version of the Scoliosis Research Society Questionnaire (SRS-22r) for use in Sweden.

SUMMARY OF BACKGROUND DATA

In modern outcome research, the patient's own view of outcome is of great importance. The SRS-22 Questionnaire has been specially designed to measure quality of life in patients with scoliosis and has been used in a number of recent studies. This questionnaire had not previously been used in Sweden.

METHODS

The SRS-22r was translated into Swedish according to accepted methods for the translation of quality-of-life questionnaires. One hundred and forty one patients answered the questionnaire together with the SF-36. Statistical analyses were performed and revealed a somewhat low internal consistency (Cronbach α) of the Function domain/SRS-22, which was found to originate in question number 18. After retranslation, another 52 patients completed the improved questionnaire. Analyses were repeated, and the results improved. When suitable, all 193 patients were therefore analyzed together.

RESULTS

Descriptive statistics, distributions, test-retest, and test for concurrent validity showed satisfactory results. After retranslation, the Cronbach alpha for all domain scores was at least 0.72. Discriminant validity was only shown for self-image and management satisfaction/dissatisfaction.

CONCLUSION

The SRS-22r Questionnaire was found to be appropriate for use in our language. Further testing for discriminant validity will be performed.

LEVEL OF EVIDENCE

N/A.

Massive bone reconstruction with heat-treated bone graft loaded autologous bone marrow-derived stromal cells and β-tricalcium phosphate composites in canine models

Bone marrow-derived stromal cells (BMSCs) contain mesenchymal stem cells that are capable of forming various mesenchymal tissues. We hypothesized that BMSCs and β-tricalcium phosphate (β-TCP) composites would promote the remodeling of large-sized autologous devitalized bone grafts; therefore, the aim of this study was to evaluate the effects of the composites on the remodeling of autologous devitalized bone grafts. Autologous BMSCs cultured in culture medium containing dexamethasone (10(-7)  M) were loaded into porous β-TCP granules under low-pressure. Theses BMSC/TCP composites were put into the bone marrow cavity of autologous heat-treated bone (femoral diaphysis, 65-mm long, 100°C, 30 min) and put back to the harvest site. In the contralateral side, β-TCP without BMSC were used in the same manner as the opposite side as the control. Treatment with the BMSC/TCP composites resulted in a significant increase in thickness, bone mineral density, and matured bone volume of the cortical bone at the center of the graft compared to the control. Histological analysis showed matured regenerated bone in the BMSC loaded group. These results indicate that BMSC/TCP composites facilitated bone regeneration and maturation at the graft site of large-sized devitalized bone. This method could potentially be applied for clinical use in the reconstruction of large bone defects such as those associated with bone tumors.

Elevation of fibrinogen due to loss of ovarian function enhances actin ring formation and leads to increased bone resorption

The aim of the present study was to evaluate the effect of fibrinogen on number and function of osteoclasts (OC) consequently resulting in bone loss. It was hypothesized that the enhanced level of released fibrinogen due to loss of ovarian function caused bone loss by acting on OCs. Bone loss was induced by ovariectomy (OVX) in mice and analyzed by micro-CT. The effect of fibrinogen on OCs was evaluated by tartrate-resistant acid phosphatase, annexin V, actin staining, pit formation observed on dentine slices, and Western blotting. Exogenous fibrinogen increased OC survival, actin ring formation, and bone resorption in vitro. The effect of fibrinogen was dependent on β(3)-integrin, which is a marker for mature OCs. Fibrinogen induced the activation of transforming oncogene from Ak strain (Akt), Ras-related C3 botulinum toxin substrate 1 (Rac1), and Rho family of GTPase (Rho) and the degradation of the Bcl-2 interacting mediator of cell death (Bim) in a manner similar to macrophage colony-stimulating factor (M-CSF). OVX increased plasma fibrinogen and serum M-CSF together with elevated actin ring formation and bone loss. The increased fibrinogen level due to loss of ovarian function may contribute, at least partly, to bone loss through the enhanced number and activity of OCs.

[Contribution of platelet concentrates to oral and maxillo-facial surgery]

INTRODUCTION

We evaluated the clinical contribution of platelet concentrates to oral and maxillo-facial surgery.

MATERIAL AND METHOD

This bibliographic research was made using the PubMed MeSH database with the following keywords: "platelet rich fibrin" (PRF), "platelet rich plasma" (PRP), "bone", "facial bone", "dental implant", and "blood platelet". The research was made without any date or language limitation since English summaries were available. All summaries were read to evaluate the relevance of the article. Only original articles and case reports were considered. The articles were classified as "in vitro studies", "animal experiments", or "clinical studies". The research was stopped on March 22, 2012.

RESULTS

One hundred and sixty-nine articles were validated after excluding irrelevant articles, reviews, technical notes, and articles without English or French summaries. Seventeen were in vitro studies, 61 animal experiments, and 91 clinical studies. One hundred and ten complete articles were read to complete summary data. The data of in vitro studies univocally supports of using platelet concentrates. The data from animal experiment studies was less consensual and the validity of animal models was contested. The disparity of clinical study designs and the lack of rigorous methodology did not allow clearly determining platelet concentrate benefits for oral and maxillo-facial surgery.

DISCUSSION

PRF or PRP clinical benefit has not been clearly demonstrated yet. French regulations relative to their use should be clarified.

Positive effect on bone fusion by the combination of platelet-rich plasma and a gelatin β-tricalcium phosphate sponge: a study using a posterolateral fusion model of lumbar vertebrae in rats

We developed a novel method for bone fusion by combining platelet-rich plasma (PRP) and a gelatin β-tricalcium phosphate (β-TCP) sponge. The PRP is an autologous concentration of platelets that includes several growth factors. The gelatin β-TCP sponge comprises gelatin and β-TCP, thus enabling the sustained release of growth factors and osteoconduction. To evaluate this method, we generated a posterolateral fusion model of lumbar vertebrae in rats and divided it into five groups by implanting the following materials between transverse processes of vertebrae, (1) the gelatin β-TCP sponge with PRP (PRP sponge), (2) the gelatin β-TCP sponge with platelet-poor plasma, (3) gelatin hydrogel with PRP, (4) autologous iliac bone (autograft), and (5) no material was implanted as a control. The assessment of bone fusion by a radiographic assessment, a biomechanical test, microcomputed tomography, and histological evaluations demonstrated that there were no significant differences between the PRP sponge and the autograft groups regarding the osteogenic effect. Subsequent examinations revealed that no significant differences existed between the PRP sponge and the autograft groups in either biomechanical stiffness or the bone volume over time; whereas the radiographic and histological composition underwent similar changes in the fusion process. These results indicate that the PRP sponge could, therefore, be potentially useful as an attractive and less invasive method for bone fusion.

Autogenous bone marrow stromal cell sheets-loaded mPCL/TCP scaffolds induced osteogenesis in a porcine model of spinal interbody fusion

This study was designed to investigate whether a tissue-engineered construct composed of autogenous cell sheets and a polycaprolactone-based bioresorbable scaffold would enhance bone regeneration and spinal interbody fusion in a large animal model. Porcine-derived autogenous bone marrow stromal cells (BMSCs) cultured into multilayered cell sheets were induced into osteogenic differentiation with dexamethasone, l-ascorbic acid, and β-glycerol phosphate. These cell sheets were assembled with bioresorbable scaffolds made from medical-grade poly(epsilon-caprolactone) incorporating 20% β-tricalcium phosphate (mPCL/TCP) as tissue-engineered BMSC constructs. L2/3, L4/5 discectomies and decortication of the vertebral end plates were performed on 16 SPF Yorkshire pigs through an anterolateral approach. The tissue-engineered BMSC constructs were transplanted into the prepared intervertebral disc spaces of half of the pigs (n = 8), whereas cell-free mPCL/TCP served as controls in the remaining pigs. New bone formation and spinal fusion were evaluated at 3 and 6 months using microcomputed tomography, histology, fluorochrome bone labeling, and biomechanical testing. New bone formation was evident as early as 3 months in the BMSC group. At 6 months, bony fusion was observed in >60% (5/8) of segments in the BMSC group. None of the control animals with cell-free scaffold showed fusion at both time points. Biomechanical evaluation further revealed a significantly increased segmental stability in the BMSC group compared with the cell-free group at 6 months postimplantation (p < 0.01). These findings suggest that mPCL/TCP scaffolds loaded with in vitro differentiated autogenous BMSC sheets could induce bone formation and interbody fusion. This in turn resulted in enhanced segmental stability of the lumbar spine.

A 1-min Method for Homogenous Cell Seeding in Porous Scaffolds

The aim of this study was to develop and evaluate a simple and rapid cell seeding procedure for both calcium phosphate ceramic scaffolds and polymer scaffolds. Poly(d,l-lactic acid) and β-tri-calcium phosphate scaffolds were seeded with MC3T3-E1 cells in a syringe. Scaffolds were put in the syringe. After replacing the plunger, the cell suspension was drawn into the syringe. The syringe was closed and the plunger was retracted to the volume of the cell suspension to create a vacuum. This was done for 3 × 10 s. By this procedure, cells were homogenously distributed throughout the scaffold. The efficiency of cell seeding was approximately 60% for both scaffolds independent of the initial cell density. The hypotension the cells experienced for 3 × 10 s did not affect the proliferation capacity of the cells. In conclusion, this method of syringe-vacuum cell seeding is easy, quick, cheap, and easily to perform at an operating theatre.