Biochemical and Biomechanical Properties of Lesion and Adjacent Articular Cartilage After Chondral Defect Repair in an Equine Model (original) (raw)

Evidence for insufficient chondrocytic differentiation during repair of full-thickness defects of articular cartilage

Matrix Biology, 1996

The main objective of this study was to characterize the cellular phenotypes in the repair tissue of full-thickness defects of articular cartilage by histologic and molecular biologic techniques. Healing of the defects in the articular cartilage of the knee joints of 12 rabbits was analyzed at days 3, 7, 14, 28 and 50 using histology and Northern analysis of mRNA levels for type I, II and III collagens and osteonectin. The cellular source of each mRNA was determined by in situ hybridization. Two novel cDNA clones for rabbit type II and III collagen mRNAs were constructed to obtain species-specific hybridization probes. The repair tissue of full-thickness defects consisted of two types of tissue. At the bottom of the defect, bone-derived cells with high levels of type I collagen and osteonectin mRNA were actively producing new osteoid, while superficially a slow transition from a fibrin clot into undifferentiated mesenchyme with cells containing type III collagen mRNA was observed. This tissue subsequently became fibrocartilaginous, with small groups of cells turning on the transcription of the type II collagen gene and acquiring a phenotype typical for hyaline cartilage. The data suggest that small clusters of cells in the repair tissue of fullthickness articular cartilage defects are capable of turning on an apparently correct chondrocytic phenotype. The low transcription level of the typeII collagen gene suggests, however, that insufficient amounts of fundamentally important regulatory factors or progenitor cells are present in the repair tissue. In the future, such factors should be administrable into the joint by novel therapeutic means.

Effects of harvest and selected cartilage repair procedures on the physical and biochemical properties of articular cartilage in the canine knee

Journal of Orthopaedic Research, 2000

This study utilizes a canine model to quantify changes in articular cartilage 15-18 weeks after a knee joint is subjected to surgical treatment of isolated chondral defects. Clinical and experimental treatment of articular cartilage defects may include implantation of matrix materials or cells, or both. Three cartilage repair methods were evaluated: microfracture, microh-acture and implantation of a type-I1 collagen matrix. and implantation of an autologous chondrocyte-seeded collagen matrix. The properties of articular cartilage in other knee joints subjected to harvest of arlicular cartilage lrom the trochlear ridge (to obtain cells for the cell-seeded procedure) were also evaluated. Physical properties (thickness, equilibrium compressive modulus, dynamic compressive stiffness, and streaming potential) and biochemical composition (hydration, glycosaminoglycan content, and DNA content) of the cartilage from sites distant to the surgical treatment were compared with values measured for site-matched controls in untreated knee joints. N o significant differences were secn in joints subjected to any of the three cartilage repair procedures. However, a number of changes were induced by the harvest operation. The largest changes (displaying up to 3-fold increases) were seen in dynamic stiffness and streaming potential of patellar groove cartilage from joints subjected to the harvest procedure. Whether the changes reported will lead to osteoarthritic degeneration is unknown, but this study provides evidence that the harvest procedure associated with autologous cell transplantation for treatment of chondral defects may result in changes in the articular cartilage in the joint.

Cell-Laden and Cell-Free Matrix-Induced Chondrogenesis versus Microfracture for the Treatment of Articular Cartilage Defects: A Histological and Biomechanical Study in Sheep

Cartilage, 2010

The aim of this study was to evaluate the regenerative potential of cell-laden and cell-free collagen matrices in comparison to microfracture treatment applied to full-thickness chondral defects in an ovine model. Animals (n = 30) were randomized into 5 treatment groups, and 7-mm full-cartilage-thickness defects were set at the trochlea and medial condyle of both knee joints and treated as follows: 2 scaffolds in comparison (collagen I/III, Chondro-Gide(®); collagen II, Chondrocell(®)) for covering microfractured defects (autologous matrix-induced chondrogenesis), both scaffolds colonized in vitro with autologous chondrocytes (matrix-associated chondrocyte transplantation), or scaffold-free microfracture technique. One year after surgery, cartilage lesions were biomechanically (indentation test), histologically (O'Driscoll score), and immunohistochemically (collagen type I and II staining) evaluated. All treatment groups of the animal model induced more repair tissue and showed ...

Role of autologous chondrocyte transplantation in articular cartilage defects: An experimental study

Indian Journal of Orthopaedics, 2013

Introduction: Injuries of articular cartilage (AC) have very limited potential to heal, because they are avascular and this may subsequently lead to secondary arthrosis. Autologous cultured chondrocytes transplantation is can be used to create hyaline or hyaline-like repair in a cartilage defect area. The purpose of this study was to repair artificially created full-thickness AC defects in 20 rabbit knee joints with autologous cultured chondrocytes. Materials and Methods: An AC defect of 3 mm was created on the lateral condyle of both tibiae. The defect was filled with autologous chondrocytes cultured in vitro and fixed with fibrin, at a later stage on the left side. The right knee acted as a control. The rabbits were sacrificed after 3, 6, and 12 weeks of transplantation and the reparative tissues were analyzed macroscopically and histologically. Results: Histological scores of the cultured autologous chondrocyte transplanted knees were significantly better than the control knees at 3, 6, and 12 weeks following the transplantation. Integration of repaired tissue with adjacent cartilage, hyaline characteristics of repaired tissue, maturity of cartilage, and cellularity increases with duration and is significant in chondrocytes-transplanted defects compared to control. The histological scores also become better with increasing duration of followup. Conclusion: Transplantation of autologous chondrocytes cultured in vitro and fixed with fibrin is effective in repairing AC defects.

Xeno-implantation of pig chondrocytes into rabbit to treat localized articular cartilage defects: an animal model

Wound Repair and Regeneration, 2004

Articular cartilage has only a limited ability to regenerate. The transplantation of autologous chondrocytes is currently used to treat focal defects in human articular cartilage, although use of organs, tissues, or cells from different species is being investigated as an alternative treatment. The object of this study was to use xeno-transplantation of cultured pig chondrocytes for the repair of rabbit chondral defects, and to analyze the significance of tissue rejection in this animal model. Partial chondral defects, including removal of cartilage tissue and a part of the subchondral bone, were created in the lateral femoral condyles of 30 adult New Zealand White rabbits. A periosteal flap was sutured to the native cartilage with the cambium layer facing the defect. As a control, culture medium was injected into the defect void of one group of rabbits while in a treatment group, chondrocytes, isolated from normal femoral pig cartilage, were injected into the defect void. All rabbits were killed by 24 weeks. Macroscopic changes of the cartilage were analyzed using Mankin's score. The distal femoral portion was studied histologically using hematoxylin and eosin, alcian blue, toluidine blue, and Mason's trichrome. Pig cells and pig genetic material were detected in the neo-synthesized tissue by immunohistochemical detection of SLA-II-DQ and polymerase chain reaction analysis of the gene SLA-II-DQB. The synovial membrane was studied histologically by hematoxylin and eosin staining. In the control group, on average, less than 25 percent of the chondral defect was filled. The repair tissue had an irregular surface with few cells similar to chondrocytes or fibroblasts and a minimal formation of extracellular matrix. In the treatment group, the chondral defect was approximately 90 percent filled with good integration between the neo-synthesized cartilage and the native cartilage. The repair tissue had a smooth surface with cells similar to chondrocytes and a hyaline-like extracellular matrix. The neo-synthesized cartilage was morphologically similar to hyaline cartilage. Importantly, there were no signs of graft-vs.-host rejections or infiltration by immune cells. In the neosynthesized tissue, pig genetic material was detected in 27 AE 5 percent of all cells. These cells containing pig genetic material were distributed throughout the neo-synthesized cartilage. We conclude that the xeno-transplantation of chondrocytes could be an alternative method for the repair of articular cartilage defects. (WOUND REP REG 2004;12:337-345) Articular cartilage is a differentiated tissue that lacks a vascular blood supply and has only limited regenerative capability. The ability of articular cartilage to selfrepair is dependent upon the depth of the cartilage lesion; purely chondral defects are unlikely to self-repair. 1 Conversely, in osteochondral defects DMEM Dulbeccos' modified Eagles medium H&E Hematoxylin and eosin PCR Polymerase chain reaction SLA Swine leukocyte antigen

Repair of porcine articular cartilage defect with autologous chondrocyte transplantation

Journal of Orthopaedic Research, 2005

Articular cartilage is known to have poor healing capacity after injury. Autologous chondral grafting remains the mainstay to treat well-defined, full-thickness, symptomatic cartilage defects. We demonstrated the utilization of gelatin microbeads to deliver autologous chondrocytes for in vivo cartilage generation. Chondrocytes were harvested from the left forelimbs of 12 Lee-Sung pigs. The cells were expanded in monolayer culture and then seeded onto gelatin microbeads or left in monolayer. Shortly before implantation, the cell-laden beads were mixed with collagen type I gel, while the cells in monolayer culture were collected and re-suspended in culture medium. Full-thickness cartilage defects were surgically created in the weight-bearing surface of the femoral condyles of both knees, covered by periosteal patches taken from proximal tibia, and sealed with a porcine fibrin glue. In total, 48 condyles were equally allotted to experimental, control, and null groups that were filled beneath the patch with chondrocyte-laden beads in gel, chondrocytes in plain medium solution, or nothing, respectively. The repair was examined 6 months post-surgery on the basis of macroscopic appearance, histological scores based on the International Cartilage Repair Society Scale, and the proportion of characteristic chondrocytes. Tensile stress-relaxation behavior was determined from uniaxial indentation tests. The experimental group scored higher than the control group in the categories of matrix nature, cell distribution pattern, and absence of mineralization, with similar surface smoothness. Both the experimental and control groups were superior to the null group in the above-mentioned categories. Viable cell populations were equal in all groups, but the proportion of characteristic chondrocytes was highest in the experimental group. Matrix stiffness was ranked as null > native cartilage > control > experimental group. Transplanted autologous chondrocytes survive and could yield hyaline-like cartilage. The application of beads and gel for transplantation helped to retain the transferred cells in situ and maintain a better chondrocyte phenotype.

Rabbit Articular Cartilage Defects Treated With Autologous Cultured Chondrocytes

Clinical Orthopaedics and Related Research, 1996

Adult New Zealand rabbits were used to transplant autologously harvested and in vitro cultured chondrocytes into patellar chondral lesions that had been made previously and were 3 mm in diameter, extending down to the calcified zone. Healing of the defects was assessed by gross examination, light microscope, and histological-histochemical scoring at 8, 12, and 52 weeks. Chondrocyte transplantation significantly increased the amount of newly formed repair tissue compared to that found in control knees in which the lesion was solely covered by a periosteal flap. In another experiment, carbon fiber pads seeded with chondrocytes were used as scaffolds, and repair significantly increased at both 12 and 52 weeks compared to knees in which scaffolds without chondrocytes were implanted. The histologic quality scores of the repair tissue were significantly better in all knees in which defects were treated with chondrocytes compared to knees treated with periosteum alone and better at 52

Chondrogenic Potential of Articular Chondrocytes Depends on Their Original Location

Tissue Engineering Part A, 2013

Objective: This study aimed to investigate the regenerative capacity of chondrocytes derived from debrided defect cartilage and healthy cartilage from different regions in the joint to determine the best cell source for regenerative cartilage therapies. Methods: Articular cartilage was obtained from Outerbridge grade III and IV cartilage lesions and from macroscopically healthy weight-bearing and nonweight-bearing (NWB) locations in the knee. Chondrocytes isolated from all locations were either pelleted directly (P0 pellets) or after expansion (P2 pellets) and analyzed for glycosaminoglycan (GAG), DNA, and cartilage-specific gene expression. Harvested cartilage samples and cultured pellets were also analyzed by Safranin O histology and immunohistochemistry for collagen I, II, and X. Immunohistochemical stainings were quantified using a computerized pixel-intensity staining segmentation method. Results: After 4 weeks of culture, the P0 pellets derived from grade III or healthy weight-bearing chondrocytes contained more ( p < 0.015) GAG and GAG normalized per DNA compared to those from grade IV and NWB locations. After expansion, these differences were lost. Cartilage-specific gene expression was higher ( p < 0.04) in P0 pellets from grade III chondrocytes compared to grade IV chondrocytes. Semiquantitative immunohistochemistry showed a more intense ( p < 0.033) collagen I and X staining for grade IV debrided cartilage compared to grade III and weight-bearing cartilage. Also, collagen type X staining intensity was higher ( p < 0.033) in NWB cartilage compared to grade III and weight-bearing regions. Conclusion: Chondrocytes derived from debrided cartilage perform better than cells from the NWB biopsy site, however, this difference is lost upon expansion. Based thereon, the debrided defect cartilage could be a viable donor site for regenerative cartilage surgery.

The present state of treatments for articular cartilage defects in the knee

Annals of The Royal College of Surgeons of England, 2012

INTRODUCTION Chondral and osteochondral lesions of the knee are notoriously difficult to treat due to the poor healing capacity of articular cartilage and the hostile environment of moving joints, ultimately causing disabling pain and early osteoarthritis. There are many different reconstructive techniques used currently but few are proven to be of value. However, some have been shown to produce a better repair with hyaline-like cartilage rather than fibrocartilage. METHODS A systematic search of all available online databases including PubMed, MEDLINE ® and Embase ™ was undertaken using several keywords. All the multiple treatment options and methods available were considered. These were summarised, and the evidence for and against them was scrutinised. RESULTS A total of 460 articles were identified after cross-referencing the database searches using the keywords. These revealed that autologous and matrix assisted chondrocyte implantation demonstrated both 'good to excellent' histological results and significant improvement in clinical outcomes. CONCLUSIONS Autologous and matrix assisted chondrocyte implantation have been shown to treat symptomatic lesions successfully with significant histological and clinical improvement. There is, however, still a need for further randomised clinical trials, perfecting the type of scaffold and the use of adjuncts such as growth factors. A list of recommendations for treatment and the potential future trends of managing these lesions are given.