Impaired differentiation potential of human trabecular bone mesenchymal stromal cells from elderly patients

Background aimsAdvances in bone tissue engineering with mesenchymal stromal cells (MSC) as an alternative to conventional orthopedic procedures has opened new horizons for the treatment of large bone defects. Bone marrow (BM) and trabecular bone are both sources of MSC. Regarding clinical use, we tested the potency of MSC from different sources.MethodsWe obtained MSC from 17 donors (mean age 64.6 years) by extensive washing of trabecular bone from the femoral head and trochanter, as well as BM aspirates of the iliac crest and trochanter. The starting material was evaluated by histologic analysis and assessment of colony-forming unit–fibroblasts (CFU-F). The MSC populations were compared for proliferation and differentiation potential, at RNA and morphologic levels.ResultsMSC proliferation potential and immunophenotype (expression of CD49a, CD73, CD90, CD105, CD146 and Stro-1) were similar whatever the starting material. However, the differentiation potential of MSC obtained by bone washing was impaired compared with aspiration; culture-amplified cells showed few Oil Red O-positive adipocytes and few mineralized areas and formed inconsistent Alcian blue-positive high-density micropellets after growth under adipogenic, osteogenic and chondrogenic conditions, respectively. MSC cultured with 1 ng/mL fibroblast growth factor 2 (FGF-2) showed better differentiation potential.ConclusionsTrabecular bone MSC from elderly patients is not good starting material for use in cell therapy for bone repair and regeneration, unless cultured in the presence of FGF-2.     

Bone marrow aspiration the posterior iliac crest,an additional safe site

The posterior iliac crest is a readily accessible site for bone marrow aspiration which is safe, psychologically less traumatic, and affords representative samples of bone marrow similar to those obtained from the sternum, the vertebral spine and the anterior iliac crest.     

BONE MARROW ASPIRATION—The Posterior Iliac Crest,an Additional Safe Site

The posterior iliac crest is a readily accessible site for bone marrow aspiration which is safe, psychologically less traumatic, and affords representative samples of bone marrow similar to those obtained from the sternum, the vertebral spine and the anterior iliac crest.     

Mathematical modelling of trabecular bone structure: the evaluation of analytical and quantified surface to volume relationships in the femoral head and iliac crest

The three-dimensional architecture of trabecular bone has structural trends related to physical function as described by Wolff's law. Mathematical modelling provides a means of analysing these structures through the use of simplified representations. A single measure of mineralized bone volume per unit volume of structure (Vv) and the surface area of mineralized bone per unit volume of structure (Sv) does not identify a particular architecture in any detail; the way in which Sv changes in relation to Vv does provide this information as the structure remodels. A series of structures using the elements of plates and rods were created. The rates of change of Sv with respect to Vv for trabecular structures give insight into differences in such models. Structures in the femoral head and iliac crest were analysed by power curve regression. In the principal compressive region, just above the medial cortex, advanced osteoarthritis was associated with a preferential loss of rods from the normal trabecular structure, resulting in a more plate-like architecture. The iliac crest remodelling that takes place in the osteoporotic appears to be the result of a generalised bone loss with some of the thinner elements of the structure being removed completely, resulting in an increase in unit cell dimension. The consequence of changing unit cell size has a major impact on surface availability for osteoblastic and osteoclastic activity. The simple plate model as a basis for the stereological analysis of trabecular structures is therefore limited because of the mixed plate and rod nature of trabecular architecture.     

Ecological Impact Assessment of the Aznalcóllar Mine Toxic Spill on Edaphic Coleopteran Communities in the Guadiamar River Basin (Southern Iberian Peninsula)

This study is part of the Restoration Program of the animal populations from the Guadiamar River basin. The main objective is to evaluate the current state of populations of the most representative groups of edaphic coleoptera in the Guadiamar River basin. In 1998, a breach in the Aznalcóllar mines retaining wall (Southern Iberian Peninsula) led to toxic sludge pouring out into this area. Systematic samples were taken from monitoring plots, scattered throughout the affected area. In order to provide an overall assessment of the fauna collected from this area in relation to adjacent areas, ecological indices were applied, and temporal course and biogeographical comparisons were also made. The results indicate that, overall, the edaphic fauna has not been significantly affected by the spillage; however, a faunistic poverty was also detected, which becomes increasingly evident closer to the accident site. Moreover, temporal evolution analysis suggests that the most affected areas are undergoing a re-colonization process, although this varies widely between species and higher taxa. This research has been financed by the Project ‘Caracterización, restauración y conservación de las comunidades animales de la cuenca del río Guadiamar’ (Characterization, Re-establishment and Conservation of the animal communities from the Guadiamar River basin). Consejería de Medio Ambiente. Junta de Andalucía (Spain).     

Comparison of phenotypic markers and neural differentiation potential of human bone marrow stromal cells from the cranial bone and iliac crest

Cellular therapies represent a new frontier in the treatment of neurological diseases. Accumulating evidence from preclinical studies of animal models suggests that mesenchymal stromal cells (MSCs), also known as mesenchymal stem cells, are an effective therapy for neurological diseases. In this study, we established human MSC lines from both cranial bone marrow (cBMMSCs) and iliac crest bone marrow (iBMMSCs) from the same donors and found that cBMMSCs show higher expression of neural crest-associated genes than iBMMSCs. Moreover, as observed in both mRNA and protein assays, neurogenic-induced cells from cBMMSCs expressed significantly higher levels of neural markers, such as NESTIN, SLUG, SOX9, and TWIST, than those from iBMMSCs. Thus, cBMMSCs showed a greater tendency than iBMMSCs to differentiate into neuron-like cells.     

Unique suites of trabecular bone features characterize locomotor behavior in human and non-human anthropoid primates

Understanding the mechanically-mediated response of trabecular bone to locomotion-specific loading patterns would be of great benefit to comparative mammalian evolutionary morphology. Unfortunately, assessments of the correspondence between individual trabecular bone features and inferred behavior patterns have failed to reveal a strong locomotion-specific signal. This study assesses the relationship between inferred locomotor activity and a suite of trabecular bone structural features that characterize bone architecture. High-resolution computed tomography images were collected from the humeral and femoral heads of 115 individuals from eight anthropoid primate genera (Alouatta, Homo, Macaca, Pan, Papio, Pongo, Trachypithecus, Symphalangus). Discriminant function analyses reveal that subarticular trabecular bone in the femoral and humeral heads is significantly different among most locomotor groups. The results indicate that when a suite of femoral head trabecular features is considered, trabecular number and connectivity density, together with fabric anisotropy and the relative proportion of rods and plates, differentiate locomotor groups reasonably well. A similar, yet weaker, relationship is also evident in the trabecular architecture of the humeral head. The application of this multivariate approach to analyses of trabecular bone morphology in recent and fossil primates may enhance our ability to reconstruct locomotor behavior in the fossil record.     

Towards validation of computational analyses of peri-implant displacements by means of experimentally obtained displacement maps

Micro-finite element (μFE) analysis has recently been introduced for the detailed quantification of the mechanical interaction between bone and implant. The technique has been validated at an apparent level. The aim of this study was to address the accuracy of μFE analysis at the trabecular level. Experimental displacement fields were obtained by deformable image registration, also known as strain mapping (SM), of dynamic hip screws implanted in three human femoral heads. In addition, displacement fields were calculated using μFE analysis. On a voxel-by-voxel basis, the coefficients of determination (R(2)) between experimental and μFE-calculated displacements ranged from 0.67 to 0.92. Linear regression of the mean displacements over nine volumes of interest yielded R(2) between 0.81 and 0.84. The lowest R(2) values were found in regions of very small displacements. In conclusion, we found that peri-implant bone displacements calculated with μFE analysis correlated well with displacements obtained from experimental SM.     

In vivo osteoinductive effect and in vitro isolation and cultivation bone marrow mesenchymal stem cells

Bone marrow contains cell type termed mesenchymal stem cells (MSC), first recognized in bone marrow by a German pathologist, Julius Cohnheim in 1867. That MSCs have potential to differentiate in vitro in to the various cells lines as osteoblast, chondroblast, myoblast and adipoblast cells lines. Aims of our study were to show in vivo capacity of bone marrow MSC to produce bone in surgically created non critical size mandible defects New Zeland Rabbits, and then in second part of study to isolate in vitro MSC from bone marrow, as potential cell transplantation model in bone regeneration. In vivo study showed new bone detected on 3D CT reconstruction day 30, on all 3 animals non critical size defects, treated with bone marrow MSC exposed to the human Bone Morphogenetic Protein 7 (rhBMP-7). Average values of bone mineral density (BMD), was 530 mg/cm3, on MSC treated animals, and 553 mg/cm3 on control group of 3 animals where non critical size defects were treated with iliac crest autologue bone graft. Activity of the Alkaline Phosphatase enzyme were measurement on 0.5, 14, 21, 30 day and increased activity were detected day 14 on animals treated with bone marrow MSCs compared with day 30 on iliac crest treated animals. That results indicates strong osteoinduction activity of the experimental bone marrow MSCs models exposed to the rhBMP-7 factor Comparing ALP activity, that model showed superiorly results than control group. That result initiates us in opinion that MSCs alone should be alternative for the autolologue bone transplantation and in vitro study we isolated singles MSCs from the bone marrow of rat's tibia and femora and cultivated according to the method of Maniatopoulos et all. The small initial colonies of fibroblast like cells were photo-documented after 2 days of primary culture. Such isolated and cultivated MSCs in future studies will be exposed to the growth factors to differentiate in osteoblast and indicate their clinically potential as alternative for conventional medicine and autologue bone transplantation. That new horizons have potential to minimize surgery and patient donor morbidity, with more success treatment in bone regenerative and metabolism diseases.     

Mechanical properties of femoral trabecular bone in dogs

Background  

Studying mechanical properties of canine trabecular bone is important for a better understanding of fracture mechanics or bone disorders and is also needed for numerical simulation of canine femora. No detailed data about elastic moduli and degrees of anisotropy of canine femoral trabecular bone has been published so far, hence the purpose of this study was to measure the elastic modulus of trabecular bone in canine femoral heads by ultrasound testing and to assess whether assuming isotropy of the cancellous bone in femoral heads in dogs is a valid simplification.     

Mesenchymal stem cells can be obtained from the human saphena vein

Mesenchymal stem cells (MSC) can be isolated from many sites adults and the fetus. Cells with osteoblastic, chondrogenic, leiomiogenic and stromogenic potentials have been obtained from the bovine artery wall, and we now show that MSC can be isolated also from the adult human vein wall. Cells detached from internal surface of the saphenous vein are cultured in vitro for 2-3 weeks and replated weekly. The culture forms a semi-confluent layer of spindle-shaped cells that are CD13(+), CD29(+), CD44(+), CD34(-), CD45(-), CD14(-), CD133(-), CD31(-), CD33(-), CD54(+), CD106(-), CD90(+), KDR(-), cadherin-5-, HLA class I(+) and HLA-DR- and differentiate in vitro into osteoblasts, chondrocytes and adipocytes. Gene expression, when compared with seven other normal tissues, shows strong similarity with MSC obtained from other sources. Three genes more expressed in saphenous MSC than in the other two MSC are related to angiogenesis, and the expression of two of them is shared by endothelial cells. These results demonstrate that the human vein wall contains mesenchymal cells with morphologic features, immunophenotypic markers, gene expression profile and differentiation potential that are similar to MSC obtained from the bone marrow and from the umbilical vein.     

Bone marrow aspiration in dogs and cats

This column describes how to obtain a bone marrow sample by way of aspiration from the iliac crest and proximal humerus of the dog and cat for the assessment and diagnosis of bone marrow disease.     

Attempt to treat congenital pseudarthrosis of the tibia with mesenchymal stromal cell transplantation

Background aimsCongenital pseudarthrosis of the tibia (CPT) caused by neurofibromatosis type 1 (NF1) is a refractory disease occurring in childhood. We present two cases that had failed all earlier treatment attempts and, as a last treatment attempt, the patients were chosen to receive mesenchymal stromal cell (MSC) transplantation prior to amputation.MethodsThe MSC from bone marrow (BM) were harvested from the iliac crest and cultured in osteoinductive medium for 3 weeks. The cultured MSC were injected in solution into BM canals of the tibia and around the resection line or bone defect in a 3-dimensional collagen sponge scaffold. After the MSC transplantation, the patients were monitored during a 10-month follow-up period. In both cases, bone formation at the pseudarthrosis site was observed and two of three treated bone defects healed. For clinical reasons not related to cell transplantation, such as new infection and pseudarthrosis and severe shortening of the leg, both extremities were finally amputated and bone samples were analyzed to evaluate MSC therapy effect and safety.ResultsMSC transplantation normalized bone remodeling, promoted bone resorption and improved the overall structure of bone. The number of osteoclasts in the cortical bone was 2-fold higher compared with the monitored situation before MSC transfer. In addition, the mineral content of the bone improved after transplantation. We could see no sign of aberrant bone formation or malignant transformation.ConclusionsOur data suggest that MSC transplantation is a possibility for treatment of CPT caused by NF1 in less severe cases without adjunct defects.     

The mechanical properties of trabecular bone: Dependence on anatomic location and function

In 1961, Evans and King documented the mechanical properties of trabecular bone from multiple locations in the proximal human femur. Since this time, many investigators have cataloged the distribution of trabecular bone material properties from multiple locations within the human skeleton to include femur, tibia, humerus, radius, vertebral bodies, and iliac crest. The results of these studies have revealed tremendous variations in material properties and anisotropy. These variations have been attributed to functional remodeling as dictated by Wolff's Law. Both linear and power functions have been found to explain the relationship between trabecular bone density and material properties. Recent studies have re-emphasized the need to accurately quantify trabecular bone architecture proposing several algorithms capable of determining the anisotropy, connectivity and morphology of the bone. These past studies, as well as continuing work, have significantly increased the accuracy of analytical and experimental models investigating bone, and bone/implant interfaces as well as enhanced our perspective towards understanding the factors which may influence bone formation or resorption.     

Isolation and characterization of mesenchymal stem cells in orthopaedics and the emergence of compact bone mesenchymal stem cells as a promising surgical adjunct

The potential clinical and economic impact of mesenchymal stem cell (MSC) therapy is immense. MSCs act through multiple pathways: (1) as “trophic” cells, secreting various factors that are immunomodulatory, anti-inflammatory, anti-apoptotic, proangiogenic, proliferative, and chemoattractive; (2) in conjunction with cells native to the tissue they reside in to enhance differentiation of surrounding cells to facilitate tissue regrowth. Researchers have developed methods for the extraction and expansion of MSCs from animal and human tissues. While many sources of MSCs exist, including adipose tissue and iliac crest bone graft, compact bone (CB) MSCs have shown great potential for use in orthopaedic surgery. CB MSCs exert powerful immunomodulatory effects in addition to demonstrating excellent regenerative capacity for use in filling boney defects. CB MSCs have been shown to have enhanced response to hypoxic conditions when compared with other forms of MSCs. More work is needed to continue to characterize the potential applications for CB MSCs in orthopaedic trauma.     

Lead concentrations in cortical and trabecular bones in deceased smelter workers

The aim of the study was to compare bone lead concentrations in cortical and trabecular bones in long-term exposed primary copper and lead smelter workers, and to relate the measured concentrations to the previous lead exposure of the workers. Lead concentrations in seven bones (trabecular: sternum, vertebrae, iliac crest, rib; cortical: femur, left forefinger, and temporal bone) were determined by electrothermal atomic absorption spectrometry in 32 male, long-term exposed copper and lead smelter workers, and compared with levels in 10 male occupationally unexposed reference persons. A time-integrated blood lead index (cumulative blood lead index, CBLI) was calculated for each worker. The lead levels in the seven studied bones were all significantly higher in active and retired lead workers as compared with the reference group (p相似文献   

Multi-lineage potential of human mesenchymal stem cells following clonal expansion

Bone marrow contains mesenchymal cells that can be isolated and grown in vitro. Using appropriate treatment protocols such cultures can be induced to differentiate to yield osteoblasts, adipocytes, and chondrocytes. However, previous experiments had not addressed the question whether single pluripotent stem cells exist and can give rise to these different cell lineages or whether bone marrow mesenchymal cell preparations represent a mixture of committed precursors. We have used human adult bone marrow-derived mesenchymal cells obtained from iliac crest biopsies to demonstrate clonal outgrowth after limiting dilution and we show that some clones can be expanded over more than 20 cumulative population doublings and differentiated to osteoblasts, adipocytes, and chondrocytes. Our data provide direct experimental evidence that cultures of bone marrow-derived mesenchymal cells contain individual cells that fulfil two essential stem cell criteria: (i) extensive self-renewal capacity and (ii) multi-lineage potential.     

Finite element analysis of trabecular bone structure: a comparison of image-based meshing techniques

In this study, we investigate if finite element (FE) analyses of human trabecular bone architecture based on 168 μm images can provide relevant information about the bone mechanical characteristics. Three human trabecular bone samples, one taken from the femoral head, one from the iliac crest, and one from the lumbar spine, were imaged with micro-computed tomography (micro-CT) using a 28 μm resolution. After reconstruction the resolution was coarsened to 168 μm. First, all reconstructions were thresholded and directly converted to FE-models built of hexahedral elements. For the coarser resolutions of two samples, this resulted in a loss of trabecular connections and a subsequent loss of stiffness. To reduce this effect, a tetrahedral element meshing based on the marching cubes algorithm, as well as a modified hexahedron meshing, which thresholds the image such that load carrying bone mass is preserved, were employed. For each sample elastic moduli and tissue Von Mises stresses of the three different 168 μm models were compared to those from the hexahedron 28 μm model. For one sample the hexahedron meshing at 168 μm produced excellent results. For the other two samples the results obtained from the hexahedral models at 168 μm resolution were poor. Considerably better results were attained for these samples when using the mass-compensated or tetrahedron meshing techniques. We conclude that the accuracy of the FE-models at 168 μm strongly depends on the bone morphology, in particular its trabecular thickness. A substantial loss of trabecular connections during the hexahedron meshing process indicates that poor FE results will be obtained. In this case the tetrahedron or mass-compensated hexahedron meshing techniques can reduce the loss of connections and produce better results than the plain hexahedron meshing techniques.     

The three-dimensional structure of trabecular bone in the femoral head of strepsirrhine primates

It has been hypothesized for over a hundred years that trabecular bone plays an important structural role in the musculoskeletal system of animals and that it responds dynamically to applied loads through growth. The objectives of this study are to quantify the three-dimensional structure of femoral head trabecular bone in a sample of extant strepsirrhines and to relate patterns of interspecific variation to locomotor behavioral differences. The bone volume fraction (BV/TV) and fabric anisotropy of trabecular bone in the femoral heads of Cheirogaleus major, Avahi laniger, Galago senegalensis, Galago alleni, Loris tardigradus, Otolemur crassicaudatus, and Perodicticus potto were quantified in three dimensions using serial high-resolution X-ray computed tomography scan data. A volume based method was used to quantify the structural anisotropy in three cubic samples located inside the central portion of the femoral head. Significant structural differences were found between the predominantly leaping galagines and indriids and the nonleaping lorisines and cheirogaleids. The leapers in general have relatively anisotropic trabecular bone. The galagines display a unique pattern of decreasing bone volume and increasing anisotropy moving from the superior to the inferior half of the femoral head. By contrast, the nonleaping taxa possess relatively uniform and isotropic bone throughout the femoral head. The differences in femoral head trabecular structure among these taxa seem to be related to locomotor behavioral differences, reflecting variation in the use and loading of the hip joint during normal locomotion.