OBJECTIVE To identify factors that are responsible for the phenotypic differences between transient chondrocytes within human osteophytes prone to endochondral ossification and permanent chondrocytes within articular cartilage persisting for decades. METHODS Differential gene expression of chondrocytes from human osteophytes or from articular cartilage was detected by cDNA microarray analysis...

Matrilin-3 is a recently identified member of the superfamily of proteins containing von Willebrand factor A-like domains and is able to form hetero-oligomers with matrilin-1 (cartilage matrix protein) via a C-terminal coiled-coil domain. Full-length matrilin-3 and a fragment lacking the assembly domain were expressed in 293-EBNA cells, purified, and subjected to biochemical characterization. R...

Joints that have degenerated as a result of aging or injury contain dead chondrocytes and damaged cartilage. Some studies have suggested that chondrocyte death precedes cartilage damage, but how the loss of chondrocytes affects cartilage integrity is not clear. In this study, we examined whether chondrocyte death undermines cartilage integrity in aging and injury using a rapid 3D confocal carti...

Osteoarthritis is characterized by a progressive degradation of articular cartilage leading to loss of joint function. The molecular mechanisms regulating pathogenesis and progression of osteoarthritis are poorly understood. Remarkably, some characteristics of this joint disease resemble chondrocyte differentiation processes during skeletal development by endochondral ossification. In healthy a...

The articular cartilage, which lines the joints of the limb skeleton, is distinct from the adjoining transient cartilage, and yet, it differentiates as a unique population within a contiguous cartilage element. Current literature suggests that articular cartilage and transient cartilage originate from different cell populations. Using a combination of lineage tracing and pulse-chase of actively...

BACKGROUND Bupivacaine and supraphysiologic temperature can independently reduce cell viability of articular chondrocytes. In combination, these 2 deleterious factors could further impair cell viability. HYPOTHESIS Hyaluronan may protect chondrocytes from death induced by bupivacaine at supraphysiologic temperatures. STUDY DESIGN Controlled laboratory study. METHODS Bovine articular chond...

INTRODUCTION: Structure and composition of articular cartilage as well as metabolic activity of chondrocytes (cartilage cells) change in osteoarthritis (OA) [1]. Among these changes, cell volume has been reported to increase [1,2]. Furthermore, the structure, composition and mechanical properties of the pericellular matrix (PCM) alter in OA [3]. However, the role of PCM in modulating volumetric...

Cartilage regeneration based on isolated and culture-expanded chondrocytes has been studied in various in vitro models, but the quality varies with respect to the morphology and the physiology of the synthesized tissues. The aim of our study was to promote in vitro chondrogenesis of human articular chondrocytes using a novel three-dimensional (3-D) cultivation system in combination with the cho...

During inflammatory joint diseases, chondrocytes are exposed to cytokines such as IL-1 that induce the synthesis of nitric oxide (NO). Chondrocytes from different zones of the articular cartilage are known to have different metabolic properties. In the present study, we have demonstrated that chondrocytes recovered from the superficial zone of normal, human, articular cartilage synthesize appro...

Articular cartilage repair techniques are challenging. Human embryonic stem cells and induced pluripotent stem cells (iPSCs) theoretically provide an unlimited number of specialized cells which could be used in articular cartilage repair. However thus far chondrocytes from iPSCs have been created primarily by viral transfection and with the use of cocultured feeder cells. In addition chondrocyt...