Bone Mesenchymal Stem Cells (BMSCs) Transplantation Can Repair Rat Femoral Head Necrosis and Inhibit the Expression of Omgp

To study the therapeutic effect of BMSCs on femoral head necrosis and whether it can inhibit the growth of OMgP. 15 healthy rats were divided into ZZ group (normal group), GT group (femoral head necrosis) and MM group (BMSCs transplantation). At 1 h, 3 h, 1 d, and 3 d, the expression of OMgP in GT group were higher than ZZ group (P <0.05) and MM group, indicating that BMSCs transplantation can decreased OMgP expression. At 1 d, 7 d, and 14 d, BBB scores of the GT group were lower than ZZ group (P < 0.05) and MM group (P < 0.05), indicating that BMSCs transplantation can improve spinal cord injury behavior. The cells in ZZ group were well stained and morphologically intact, the femoral head was not damaged, and the articular surface was smooth, GT group had cartilage necrosis with disordered inferior epiphysis, and the femoral head of the MM group had less damage and increased osteoblasts. The blood vessel counts in necrotic area in GT group were higher than ZZ group and MM group with decreased new bone area in repair area compared to ZZ and MM group (P <0.05), indicating that the area of femoral head necrosis after BMSCs transplantation was improved. The levels of ALP and BGP in GT group were lower than ZZ group (P <0.05) and MM group (P <0.05). Bone marrow mesenchymal stem cell transplantation can effectively repair new bone area, up-regulate ALP and BGP, and have a positive effect on femoral head necrosis, possibly by inhibiting OMGP activity.

In Vivo Efficacy of Neutrophil-Mediated Bone Regeneration Using a Rabbit Calvarial Defect Model

Reconstruction of bone due to surgical removal or disease-related bony defects is a clinical challenge. It is known that the immune system exerts positive immunomodulatory effects on tissue repair and regeneration. In this study, we evaluated the in vivo efficacy of autologous neutrophils on bone regeneration using a rabbit calvarial defect model. Methods: Twelve rabbits, each with two surgically created calvarial bone defects (10 mm diameter), were randomly divided into two groups; (i) single application of neutrophils (SA-NP) vs. SA-NP control, and (ii) repetitive application of neutrophils (RA-NP) vs. RA-NP control. The animals were euthanized at 4 and 8 weeks post-operatively and the treatment outcomes were evaluated by micro-computed tomography, histology, and histomorphometric analyses. Results: The micro-CT analysis showed a significantly higher bone volume fraction (bone volume/total volume) in the neutrophil-treated groups, i.e., median interquartile range (IQR) SA-NP (18) and RA-NP (24), compared with the untreated controls, i.e., SA-NP (7) and RA-NP (14) at 4 weeks (p < 0.05). Similarly, new bone area fraction (bone area/total area) was significantly higher in neutrophil-treated groups at 4 weeks (p < 0.05). Both SA-NP and RA-NP had a considerably higher bone volume and bone area at 8 weeks, although the difference was not statistically significant. In addition, immunohistochemical analysis at 8 weeks revealed a higher expression of osteocalcin in both SA-NP and RA-NP groups. Conclusions: The present study provides first hand evidence that autologous neutrophils may have a positive effect on promoting new bone formation. Future studies should be performed with a larger sample size in non-human primate models. If proven feasible, this new promising strategy could bring clinical benefits for bone defects to the field of oral and maxillofacial surgery.

Efficacy for Whitlockite for Augmenting Spinal Fusion

Whitlockite (WH) is the second most abundant inorganic component of human bone, accounting for approximately 25% of bone tissue. This study investigated the role of WH in bone remodeling and formation in a mouse spinal fusion model. Specifically, morphology and composition analysis, tests of porosity and surface area, thermogravimetric analysis, an ion-release test, and a cell viability test were conducted to analyze the properties of bone substitutes. The MagOss group received WH, Group A received 100% beta-tricalcium phosphate (β-TCP), Group B received 100% hydroxyapatite (HAp), Group C received 30% HAp/70% β-TCP, and Group D received 60% HAp/40% β-TCP (n = 10 each). All mice were sacrificed 6 weeks after implantation, and micro-CT, hematoxylin and eosin (HE) staining, and Masson trichome (MT) staining and immunohistochemistry were performed. The MagOss group showed more homogeneous and smaller grains, and nanopores (<500 nm) were found in only the MagOss group. On micro-CT, the MagOss group showed larger fusion mass and better graft incorporation into the decorticate mouse spine than other groups. In the in vivo experiment with HE staining, the MagOss group showed the highest new bone area (mean: decortication group, 9.50%; A, 15.08%; B, 15.70%; C, 14.76%; D, 14.70%; MagOss, 22.69%; p < 0.0001). In MT staining, the MagOss group demonstrated the highest new bone area (mean: decortication group, 15.62%; A, 21.41%; B, 22.86%; C, 23.07%; D, 22.47%; MagOss, 26.29%; p < 0.0001). In an immunohistochemical analysis for osteocalcin, osteopontin, and CD31, the MagOss group showed a higher positive area than other groups. WH showed comparable bone conductivity to HAp and β-TCP and increased new bone formation. WH is likely to be used as an improved bone substitute with better bone conductivity than HAp and β-TCP.

Patients Diagnosed with Myelodysplastic Syndromes Display Lower Bone Mass: Assessment Using Bone Marrow Biopsies Manually and with Artificial Intelligence

Background: Murine models of myelodysplastic syndromes (MDS) exhibit lower bone mass (B-Mass), and several reports suggest increased incidence of osteoporosis and fractures in MDS patients. Whether MDS is associated with lower B-Mass is unknown. Aims: 1) to develop a simple method to estimate trabecular B-Mass from bone marrow biopsies (BMB); 2) to compare the trabecular B-Mass of MDS patients at diagnosis and non-MDS controls; 3) to develop an artificial intelligence (AI) algorithm for automated trabecular B-Mass assessment. Methods: In this study we included male patients age ≥ 65 years old with "lower-risk" (LR) MDS, diagnosed at Tel Aviv Sourasky Medical Center, between 2011 and 2019 and age-matched controls undergoing bone marrow (BM) biopsy for either unexplained anemia or as a part of staging work-up for newly diagnosed lymphoma. BM slides (H&E stain) were digitally scanned. The total relevant area (TRA, Figure 1A) was identified and bone trabeculae were manually contoured using Adobe Photoshop software. Bone area (BA, figure 1B) was calculated as the sum of all contoured pixels of bone, and B-Mass = BA/TRA(%). The manually annotated data were used to develop a preliminary AI algorithm to automatically detect the BA as well as BM fat for use in the current and future research in the field. The Sørensen-Dice similarity coefficient (DSC) was used to assess agreement between manual and AI annotations. Results: There were 43 MDS and 36 control patients with mean ages of 80 and 78 years (p&gt;0.05), respectively. Comorbidities in both groups were similar. Notably, trabecular B-Mass of MDS was significantly lower than that of controls: 11.6% [95%CI 9.9-13.3] vs 18.3% [16.6-20.3], respectively (p&lt;0.0001). This represented a 37% relative reduction for MDS patients compared to controls. Next, the manually annotated data used to develop an AI algorithm automatically assessed trabecular B-Mass. The devised algorithm, tested on 17 patient samples, yielded a DSC (Mean ± SEM) of 0.76 ± 0.015 and 0.81 ± 0.02 for bone and fat respectively (Figure 1C and 1D). Conclusions: We have developed a simple technique to estimate trabecular B-Mass based on available BM sections. Importantly, we found that trabecular B-Mass of LR-MDS patients is compromised already at diagnosis. In addition, automated (AI) assessment of B-Mass using available H&E-stained BM slides is feasible and clinically relevant for patients with MDS and other hematological malignancies. Future work will develop the AI technique and expand it to identify all components of the BM, including the cellular compartment. This will enhance our understanding of the osteohematological niche in such patients, and aid in diagnosis as well as treatment planning. This study was supported by a grant from the Dotan Hemato-oncology Fund, the Cancer Biology Research Center, Tel Aviv University to DN, MM and HSO. Figure 1: Bone marrow biopsy (BMB) slide of a representative patient showing (A) the total relevant area, and (B) the bone area - TRA and BA respectively. Demonstrating the artificial intelligence (AI) technique for the same patient, we compare (C) manual annotation to (D) AI-based annotation of both bone (red) and fat (green). Figure 1 Figure 1. Disclosures Mittelman: Janssen · Roche · Novartis · Takeda · Medison / Amgen · Neopharm / Celgene / BMS · Abbvie · Gilead: Research Funding; Novartis · Takeda · Fibrogen · Celgene / BMS · Onconova · Geron: Other: Clini; Onconova · Novartis · Takeda · Silence: Membership on an entity's Board of Directors or advisory committees; MDS HUB: Consultancy; Celgene / BMS · Novartis: Speakers Bureau.

COMBINED USE OF HYALURONIC ACID WITH NANO-BIOACTIVE GLASS ENHANCED BIOCEMENT BASED SILICATE STIMULATED BONE REGENERATIVE CAPACITY IN TIBIAL BONE DEFECTS OF RABBITS: IN-VIVO STUDY

An ideal biomaterial for bone regeneration is a longstanding quest nowadays. This study aimed to evaluate the osteogenic potentiality of nano-bioactive glass enhanced biocement based silicate with or without hyaluronic acid seeded in rabbits’ tibial bone defects. For this, 24 male rabbits with two 5 mm defects (1 defect per tibia) were divided into three equal groups. Among the predefined three groups, for the rabbits of group 1(control) bone defects were left untreated while for the members of group 2 defects received nano-bioactive glass enhanced biocement based silicate cement, and group 3 defects received nano-bioactive glass cement mixed with hyaluronic acid. Animals of each group were divided equally for euthanization after 3 and 6 weeks. Bone specimens were processed and examined histologically with histomorphometrically analysis of new bone area percentage. The bone defects in group 3 showed significantly improved osseous healing histologically as compared to the group 1&2. The morphometric analysis also revealed a significant increase in the new bone area percentage in group 3 as compared to the group 1 and 2 (P < 0.05). The results of the present study can be concluded that bone defects could be treated with nano-bioactive glass and hyaluronic acid cement. Although, nano-bioactive glass alone was capable of bone regeneration the combination of both had significant regenerative capacity.

Bone induction and defect repair by true bone ceramics incorporated with rhBMP-2 and Sr

Objective: To study the bone induction and defect repair of true bone ceramics (TBC) combined with rhBMP-2 and Sr. Methods: MC3T3-E1 cells were used to evaluate the bioactivity of the composite. Cell proliferation activity was detected by CCK-8, ALP activity was detected by p-nitrophenyl phosphate (PNPP), and the differences of material surface topography were observed by scanning electron microscopy (SEM). Bone induction was verified by the implantation in nude mice. The rabbit femoral condyle defect model was achieved to verify the bone defect repair ability of the material. Results: SEM results showed nearly the same surface morphology and cell proliferation quantified by CCK-8 showed that compared with TBC, both TBC&Sr and TBC&BMP-2&Sr had a significant promoting effect (P < 0.05). ALP activity result showed that the ALP activity of TBC&BMP-2&Sr was significantly higher than that of TBC alone (P < 0.05). The bone induction result showed that TBC&Sr had a small amount of new bone formation, and the new bone area was only 2.5 ± 0.11%. The bone induction activity of TBC&BMP-2&Sr was the highest, the new bone area was up to 75.36 ± 4.21%. Histological result of bone defect repair showed that TBC&BMP-2&Sr was also the highest, the new bone area was up to 72.42 ± 3.14%. The repair effect of TBC& BMP-2 was second, and better than that of TBC&Sr. Conclusion: TBC combined with rhBMP-2 and Sr had the good bioactivity, obvious bone conduction and bone defect repair performance, laying the foundation of clinical application potentially.

Clinical Efficacy of Polycaprolactone β-Calcium Triphosphate Composite for Osteoconduction in Rabbit Bone Defect Model

The combination of β-tricalcium phosphate (β-TCP) with polycaprolactone (PCL) has been considered a promising strategy for designing scaffolds for bone grafting. This study incorporated PCL with commercially available β-TCP (OsteoceraTM) to fabricate an injectable bone substitute and evaluate the effect of PCL on compressive strength and setting time of the hydraulic cement. The mechanical testing was compliant with the ASTM D695 and ASTM C191-13 standards. Results showed that PCL-TCP composite presented a well-defined architecture with uniform pore distribution and a significant increase in compressive strength compared with β-TCP alone. Eighteen rabbits, each with two surgically created bone defects, were treated using the PCL-TCP composites. The composite materials were resorbed and replaced by newly formed bone tissue. Both PCL-TCP and β-TCP demonstrated equivalent clinical effects on osteoconduction property in terms of the percentage of newly formed bone area measured by histomorphometric analysis. PCL-TCP was proven to be as effective as the commercially available β-TCP scaffold (OsteoceraTM).

Micro-computed tomography analysis of the lumbar pedicle wall

Background Although the pedicle is routinely used as a surgical fixation site, the pedicle wall bone area fraction (bone area per unit area) and its distribution at the isthmus of the pedicle remain unknown. The bone area fraction at the pedicle isthmus is an important factor contributing to the strength of pedicle screw constructs. This study investigates the lumbar pedicle wall microstructure based on micro-computed tomography. Methods Six fresh-frozen cadaveric lumbar spines were analyzed. Left and right pedicles of each vertebra from L1 to L5 were resected for micro-computed tomography scanning. Data was analyzed with custom-written software to determine regional variation in pedicle wall bone area fraction. The pedicular cross-section was divided into four regions: lateral, medial, cranial, and caudal. The mean bone area fraction values for each region were calculated for all lumbar spine levels. Results The lateral region showed lower bone area fraction than the medial region at all spinal levels. Bone area fraction in the medial region was the highest at all levels except for L4, and the median values were 99.8% (95.9–100%). There were significant differences between the lateral region and the caudal region at L1, L2 and L3, but none at L4 and L5. The bone area fraction in the lateral region was less than 64% at all spinal levels and that in the caudal region was less than 67% at the L4 and L5 levels. Conclusions This study provides initial detailed data on the lumbar pedicle wall microstructure based on micro-computed tomography. These findings may explain why there is a higher incidence of pedicle screw breach in the pedicle lateral and caudal walls.

Type 2 diabetes and Change in Total Hip Bone Area and Bone Mineral Density in Elderly Swedish Men and Women

Context In a cross-sectional study, we found an association between type 2 diabetes mellitus (T2DM) and smaller bone area together with a greater bone mineral density (BMD) at the total hip. Objective To investigate these associations longitudinally, by studying T2DM status (no T2DM n=1521, incident T2DM n=119 or prevalent T2DM n=106) in relation to changes in total hip bone area and BMD. Methods In three cohorts, the Swedish Mammography Cohort Clinical (SMCC; n=1060, Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS; n=483) and Uppsala Longitudinal Study of Adult Men (ULSAM; n=203), with repeat assessment of T2DM status and dual energy x-ray absorptiometry (DXA) measurements of total hip bone area and BMD on average 8 years apart, a linear regression model was used to assess the effect of T2DM status on change in bone area and BMD at the total hip. Results After meta-analysis, the change in bone area at the total hip was 0.5% lower among those with incident T2DM compared to those without T2DM (-0.18 cm 2 [95% CI -0.30, -0.06]). The change in bone area was similar among those with prevalent T2DM compared to those without (0.00 cm 2 [95% CI -0.13, 0.13]). For BMD, the combined estimate was 0.004 g/cm 2 (95% CI -0.006, 0.014) among those with incident T2DM and 0.010 g/cm 2 (95% CI -0.000, 0.020) among those with prevalent T2DM, compared to those without T2DM. Conclusion Those with incident T2DM have a lower expansion in bone area at the total hip compared to those without T2DM.

Driving β2- While Suppressing α-Adrenergic Receptor Activity Suppresses Joint Pathology in Inflammatory Arthritis

ObjectiveHypersympathetic activity is prominent in rheumatoid arthritis, and major life stressors precede onset in ~80% of patients. These findings and others support a link between stress, the sympathetic nervous system and disease onset and progression. Here, we extend previous research by evaluating how selective peripherally acting α/β2-adrenergic drugs affect joint destruction in adjuvant-induced arthritis.MethodsComplete Freund’s adjuvant induced inflammatory arthritis in male Lewis rats. Controls received no treatment. Arthritic rats then received vehicle or twice-daily treatment with the α-adrenergic antagonist, phentolamine (0.5 mg/day) and the β2-adrenergic agonist, terbutaline (1200 µg/day, collectively named SH1293) from day (D) of disease onset (D12) through acute (D21) and severe disease (D28). Disease progression was assessed in the hind limbs using dorsoplantar widths, X-ray analysis, micro-computed tomography, and routine histology on D14, D21, and D28 post-immunization.ResultsOn D21, SH1293 significantly attenuated arthritis in the hind limbs, based on reduced lymphocytic infiltration, preservation of cartilage, and bone volume. Pannus formation and sympathetic nerve loss were not affected by SH1293. Bone area and osteoclast number revealed high- and low-treatment-responding groups. In high-responding rats, treatment with SH1293 significantly preserved bone area and decreased osteoclast number, data that correlated with drug-mediated joint preservation. SH1293 suppressed abnormal bone formation based on reduced production of osteophytes. On D28, the arthritic sparing effects of SH1293 on lymphocytic infiltration, cartilage and bone sparing were maintained at the expense of bone marrow adipocity. However, sympathetic nerves were retracted from the talocrural joint.Conclusion and SignificanceOur findings support a significant delay in early arthritis progression by treatment with SH1293. Targeting sympathetic neurotransmission may provide a strategy to slow disease progression.