Biorheology - Volume 43, issue 3-4

Authors: Botter, S.M. | van Osch, G.J.V.M. | Waarsing, J.H. | Day, J.S. | Verhaar, J.A.N. | Pols, H.A.P. | van Leeuwen, J.P.T.M. | Weinans, H.

Article Type: Research Article

Abstract: In the past few years there has been a considerable interest in the role of bone in osteoarthritis. Despite the increasing evidence of the involvement of bone in osteoarthritis, it remains very difficult to attribute the cause or effect of changes in subchondral bone to the process of osteoarthritis. Although osteoarthritis in mice provides a useful model to study changes in the subchondral bone, detailed quantification of these changes is lacking. Therefore, the goal of this study was to quantify subchondral bone changes in a murine osteoarthritis model by use of micro-computed tomography (micro-CT). We induced osteoarthritis-like characteristics in the …knee joints of mice using collagenase injections, and after four weeks we calculated various 3D morphometric parameters in the epiphysis of the proximal tibia. The collagenase injections caused cartilage damage, visible in histological sections, particularly on the medial tibial plateau. Micro-CT analysis revealed that the thickness of the subchondral bone plate was decreased both at the lateral and the medial side. The trabecular compartment demonstrated a small but significant reduction in bone volume fraction compared to the contralateral control joints. Trabeculae in the collagenase-injected joints were thinner but their shape remained rod-like. Furthermore, the connectivity between trabeculae was reduced and the trabecular spacing was increased. In conclusion, four weeks after induction of osteoarthritis in the murine knee subtle but significant changes in subchondral bone architecture could be detected and quantified in 3D with micro-CT analysis. Show more

Citation: Biorheology, vol. 43, no. 3-4, pp. 379-388, 2006

Authors: Quasnichka, Helen L. | Anderson-MacKenzie, Janet M. | Bailey, Allen J.

Article Type: Research Article

Abstract: There is increasing recognition that osteoarthritis (OA) is a complex disease involving the whole synovial joint, rather than the articular cartilage alone, however its aetiology and pathogenesis is not understood. Our initial studies revealed elevated turnover of bone and ligament collagen in human and mouse OA, respectively. To investigate the relative appearance of pathology in cartilage, bone and ligament, we studied the progression of spontaneous OA in the Dunkin–Hartley (DH) guinea pig knee, and compared with age-matched control Bristol Strain 2 (BS2) knees. The classical radiographic OA score of the DH knees compared to BS2 knees was 2-fold higher at …24 weeks of age. The patella perimeter and subchondral bone density was significantly greater in the DHs at 24 and 36 weeks compared to BS2. The femoral intercondylar notch width was found to be significantly lower in the DHs at 24 and 36 weeks, compared to BS2, indicating bone remodelling at the cruciate ligament (CL) insertion site. We found significantly greater laxity of the DH anterior CL at 12, 16 and 20 weeks compared to BS2. This elevated laxity was associated with increased remodelling of the CLs, based on markers of collagen turnover, and occurred prior to bone and cartilage pathology. We propose that the laxity of the CL leads to remodelling of the subchondral bone, and intercondylar notch, due to a change in load through the joint. Remodelling of the CLs and bone occurs prior to and concomitant with histopathological changes in the articular cartilage respectively, demonstrating the fundamental role of the ligament and subchondral bone in the aetiology of knee OA. Show more

Keywords: Osteoarthritis, subchondral bone, ligaments, collagen, metabolism, biomechanics, notch width

Citation: Biorheology, vol. 43, no. 3-4, pp. 389-397, 2006

Article Type: Other

Citation: Biorheology, vol. 43, no. 3-4, pp. 401-402, 2006

Authors: Watrin-Pinzano, Astrid | Etienne, Stéphanie | Grossin, Laurent | Gaborit, Nadège | Cournil-Henrionnet, Christel | Mainard, Didier | Netter, Patrick | Gillet, Pierre | Galois, Laurent

Article Type: Research Article

Keywords: Cartilage, osteoarthritis, apoptosis, caspase, experimental model

Citation: Biorheology, vol. 43, no. 3-4, pp. 403-412, 2006

Authors: Chowdhury, Tina T. | Bader, Dan L. | Lee, David A.

Article Type: Research Article

Abstract: . NO and PGE2 are inflammatory mediators derived from the inducible iNOS and COX enzymes and are potentially important pharmacological targets in OA. Both mechanical loading and IL-1β will influence the release of . NO and PGE2 . Accordingly, the current study examines the effect of dynamic compression on . NO and PGE2 release by human chondrocytes cultured in agarose constructs in the presence and absence of selective iNOS and COX-2 inhibitors. The current data demonstrate that IL-1β induced nitrite and PGE2 release and inhibited [3 H]-thymidine and 35 SO4 incorporation. Inhibitor experiments indicate that 1400W …and NS-398 either partially reversed or abolished IL-1β induced nitrite and PGE2 release. IL-1β induced inhibition of cell proliferation and proteoglycan synthesis was partially reversed with 1400W but was not influenced by NS-398. For the dynamic loading experiments, 1400W and NS-398 either reduced or abolished the compression-induced inhibition of . NO and PGE2 release in the presence of IL-1β. The IL-1β induced inhibition of cell proliferation was not influenced by 1400W or NS-398 whereas strain-induced stimulation of proteoglycan synthesis in the presence of IL-1β was enhanced by 1400W. The data obtained using human chondrocytes demonstrate that IL-1β induced . NO and PGE2 release via an iNOS-driven-COX-2 inter-dependent pathway. This response could be reversed by dynamic compression. These data indicate interactions exist between the NOS and COX pathways, a finding which will provide new insights in the development of pharmacological or biophysical treatments for cartilage disorders such as OA. Show more

Keywords: Nitric oxide, PGE$_{2}$, mechanotransduction, osteoarthritis

Citation: Biorheology, vol. 43, no. 3-4, pp. 413-429, 2006

Authors: Schumann, D. | Kujat, R. | Zellner, J. | Angele, M.K. | Nerlich, M. | Mayr, E. | Angele, P.

Article Type: Research Article

Abstract: This study examined the effects of low intensity pulsed ultrasound (LIPUS) on human bone marrow-derived mesenchymal stem cells undergoing chondrogenic differentiation. Aggregates of mesenchymal stem cells and mesenchymal stem cells seeded in three dimensional matrices were cultured in a defined chondrogenic medium and subjected to LIPUS for the first 7 days of culture. At 1, 7, 14 and 21 days, samples were harvested for histology, immunohistochemistry, RT-PCR, and quantitative DNA and matrix macromolecule analysis. Cell aggregates with daily treatment for 20 minutes showed no significant differences for proteoglycan and collagen content during chondrogenic differentiation. However ultrasound application for 40 minutes …daily resulted in a statistically significant increase of the proteoglycan and collagen content after 21 days in culture. Aggregates treated for 20 minutes daily showed decreased expression of chondrogenic genes at all time points. In contrast, 40 minutes of daily treatment of aggregates resulted in a significant increase of chondrogenic marker genes after an initial decrease at day 7 with time in culture. Ultrasound treated cell-scaffold constructs showed a significant increase of chondrogenic marker gene expression and extracellular matrix deposition. This study indicates that LIPUS can be used to enhance the chondrogenesis of mesenchymal stem cells in cell aggregates and cell-scaffold constructs. We have found a dependency on the specific treatment parameters. We hypothesize that LIPUS can be used for an improved in vitro preparation of optimized tissue engineering implants for cartilage repair. Furthermore this non-invasive method could also be of potential use in vivo for regenerative therapy of cartilage in the future. Show more

Keywords: Chondrogenesis, stem cell, bone marrow, mechanobiology, ultrasound

Citation: Biorheology, vol. 43, no. 3-4, pp. 431-443, 2006

Authors: Hiraoka, Koji | Grogan, Shawn | Olee, Tsaiwei | Lotz, Martin

Article Type: Research Article

Abstract: The transmembrane receptor Notch-1 regulates cell fate and differentiation and was suggested to identify a cell type with progenitor characteristics in newborn bovine articular cartilage. We show that Notch-1 is expressed on >70% of BM-MSC in early passage monolayer culture. We also demonstrate that normal articular cartilage contains Notch-1+ cells and that the frequency is increased in OA. Most Notch-1+ cells in OA cartilage are located in the clusters of proliferating cells. These findings indicate that multipotential mesenchymal progenitor cells are present in articular cartilage from adult humans and that their frequency is increased in OA. This observation has implications …for understanding the intrinsic repair capacity of articular cartilage and raises the possibility that these progenitor cells might be involved in the pathogenesis of arthritis. Show more

Citation: Biorheology, vol. 43, no. 3-4, pp. 447-454, 2006

Authors: Campbell, Jonathan J. | Lee, David A. | Bader, Dan L.

Article Type: Research Article

Abstract: This study tests the hypothesis that dynamic compressive strain selectively enhances chondrogenic differentiation by human mesenchymal stem cells (MSCs). Primary MSCs were isolated and expended in monolayer culture. The cells were seeded in alginate constructs or in pellet culture. The time course of chondrogenic differentiation was assessed by real-time QPCR of mRNA expression analysis for cartilage specific markers. Collagen types II and X mRNA, not present in undifferentiated MSCs, were detectable by 2–4 days of chondrogenic induction and continued to rise significantly throughout the culture period of 10 days (p<0.001). Basal levels of gene expression for Sox-9 and aggrecan were …evident in undifferentiated MSCs, although chondrogenic induction for a period of 8 days resulted in an increased trend in the gene expression levels. The alginate system was also used in mechanical conditioning studies. Dynamic compression was applied, in an intermittent regimen, at a strain amplitude of 15% and frequency of 1 Hz in the presence and absence of 10 ng/ml TGFβ3 , for a period of 8 days. Results indicated significant changes in the levels of mRNA expression for the chondrogenic markers. For example, by day 8, the application of the strain regimen alone caused an up-regulation in all the chondrogenic markers compared to the control samples (no TGFβ, no compression). However, the combined effects of strain and TGFβ on these markers were more complex than purely additive. Show more

Citation: Biorheology, vol. 43, no. 3-4, pp. 455-470, 2006

Authors: Facchini, Andrea | Lisignoli, Gina | Cristino, Sandra | Roseti, Livia | De Franceschi, Luciana | Marconi, Emanuele | Grigolo, Brunella

Article Type: Research Article

Abstract: The development of improved methods for treatment of chondral defects using autologous cells in combination with biomaterials leads to a new generation of implantable devices. Their association gives rise to a hybrid construct combining biological and material components that can be specifically committed. The comprehension of cellular and molecular mechanisms of cartilage repair and the use of biomaterials in combination with chondrocytes or mesenchymal stem cells in the treatment of cartilage defects has opened a new era of therapeutical strategies. Recently, their applicability in the treatment of early lesions in osteoarthritis is under investigation. To obtain new information on the …behaviour of chondrocytes and mesenchymal stem cells grown on a hyaluronan derivative scaffold (Hyaff® -11) already used in cartilage repair, we analysed a series of molecules expressed by these cells by Real-Time RT-PCR and immunohistochemical analyses. The data obtained with this work showed that this biomaterial is able to reduce the expression of some catabolic molecules by human chondrocytes and provide a good environment to support the differentiation of mesenchymal stem cells in chondrogenic sense. These observations confirm Hyaff® -11 as a suitable scaffold both for chondrocytes and mesenchymal stem cells for the treatment of articular cartilage defects. Show more

Keywords: Human chondrocytes, mesenchymal stem cells, hyaluronan-based scaffold, chondrogenic differentiation

Citation: Biorheology, vol. 43, no. 3-4, pp. 471-480, 2006

Authors: Wendt, D. | Stroebel, S. | Jakob, M. | John, G.T. | Martin, I.

Article Type: Research Article

Abstract: In this work, we assessed whether culture of uniformly seeded chondrocytes under direct perfusion, which supplies the cells with normoxic oxygen levels, can maintain a uniform distribution of viable cells throughout porous scaffolds several milimeters in thickness, and support the development of uniform tissue grafts. An integrated bioreactor system was first developed to streamline the steps of perfusion cell seeding of porous scaffolds and perfusion culture of the cell-seeded scaffolds. Oxygen tensions in perfused constructs were monitored by in-line oxygen sensors incorporated at the construct inlet and outlet. Adult human articular chondrocytes were perfusion-seeded into 4.5 mm thick foam scaffolds …at a rate of 1 mm/s. Cell-seeded foams were then either cultured statically in dishes or further cultured under perfusion at a rate of 100 μm/s for 2 weeks. Following perfusion seeding, viable cells were uniformly distributed throughout the foams. Constructs subsequently cultured statically were highly heterogeneous, with cells and matrix concentrated at the construct periphery. In contrast, constructs cultured under perfusion were highly homogeneous, with uniform distributions of cells and matrix. Oxygen tensions of the perfused medium were maintained near normoxic levels (inlet ≅ 20%, outlet > 15%) at all times of culture. We have demonstrated that perfusion culture of cells seeded uniformly within porous scaffolds, at a flow rate maintaining a homogeneous oxygen supply, supports the development of uniform engineering tissue grafts of clinically relevant thicknesses. Show more

Keywords: Bioreactor, fluid flow, chondrocyte, mass transport, functional tissue engineering

Citation: Biorheology, vol. 43, no. 3-4, pp. 481-488, 2006