Hyaline Cartilage Tissue Research Articles

Joint immobilization inhibits spontaneous hyaline cartilage regeneration induced by a novel double-network gel implantation

We have recently discovered that spontaneous hyaline cartilage regeneration can be induced in an osteochondral defect in the rabbit, when we implant a novel double-network (DN) gel plug at the bottom of the defect. To clarify whether joint immobilization inhibits the spontaneous hyaline cartilage regeneration, we conducted this study with 20 rabbits. At 4 or 12weeks after surgery, the defect in the mobile knees was filled with a sufficient volume of the hyaline cartilage tissue rich in proteoglycan and type-2 collagen, while no cartilage tissues were observed in the defect in the immobilized knees. Type-2 collagen, Aggrecan, and SOX9 mRNAs were expressed only in the mobile knees at each period. This study demonstrated that joint immobilization significantly inhibits the spontaneous hyaline cartilage regeneration induced by the DN gel implantation. This fact suggested that the mechanical environment is one of the significant factors to induce this phenomenon.

THE NEW PLASTIC METHOD OF ARTICULAR HYALINE CARTILAGE DEFECTS WITH COMBINED CELLULAR-TISSUE GRAFT

The new method of restoration of injured articular cartilage using plasty of intraoperative bone-cartilage defects with combined allograft based on biologic porous carrier and cell culture from stroma of costal cartilage. The transplantation of allogenic culture of chondroblast cells on demineralized spongy substance «Lioplast» ensure еру the formation of hyaline cartilage tissue on the site of defect and amplified development of microcirculatory network in subchondral bone. The heterotopic principle obtaining cellular material allows to perform low-traumatic operations.

Surgical Removal of Chondroma of the Petrous Apex Resulting in Hearing Improvement -Case Report-

An 18-year-old male presented with a chondroma in the petrous apex manifesting as major complaints of headaches and sensorineural hearing disturbance on the right. Head computed tomography and magnetic resonance imaging revealed a neoplastic lesion in the right petrous apex, which had bulged to compress the internal auditory meatus. Surgical removal improved his hearing with normalization of the postoperative air conduction threshold by reduction of the pressure of the internal auditory meatus, suggesting that the function of the cochlea was retained and the tumor was compressing the cochleal nerve at the level of the internal auditory meatus. Histological examination showed the tumor consisted of hyaline cartilage tissue without cellular atypia and the diagnosis was chondroma.

Stem cell therapy for cartilage regeneration in osteoarthritis

Enhancing the regeneration potential of hyaline cartilage tissue remains a great challenge. During embryonic development, some of the cells of the inner cell mass will turn into the mesoderm. This will be the founder of the mesenchymal cells in connective tissues of adult life, such as bone, tendon, muscle, and cartilage. Some of these embryonic mesenchymal cells are believed not to differentiate, but reside in each of the tissues. These are now collectively described as adult mesenchymal stem cells, which are thought to be capable of repairing injured tissue. We will briefly summarize the current knowledge about stem cell-related cells in cartilage tissue and carefully discuss the potential of the cell population we described recently as a starting-point for a regenerative therapy for osteoarthritis. We found that repair tissue from human articular cartilage during the late stages of osteoarthritis harbors a unique progenitor cell population, termed chondrogenic progenitor cells (CPC). These exhibit stem cell characteristics combined with a high chondrogenic potential. They offer new insights into the biology of progenitor cells and may be relevant in the development of novel therapeutic approaches for a cell-based therapy for late stages of osteoarthritis.

In VitroandIn VivoChondrogenesis of Rabbit Bone Marrow–Derived Stromal Cells in Fibrin Matrix Mixed with Growth Factor Loaded in Nanoparticles

The effects of growth factor loaded in nanoparticles mixed in fibrin constructs on chondrogenic differentiation were investigated by evaluating the specific cartilage extracellular matrix components in vitro and in vivo using a special cell source of bone marrow-derived stromal cells (BMSCs). The proliferation of cultured and transplanted BMSCs was found to be greater in fibrin constructs that contained TGF-beta3-loaded nanoparticles and TGF-beta3 alone than in constructs that contained unloaded nanoparticles or in fibrin hydrogel alone. Further, reverse transcriptase-polymerase chain reaction revealed that BMSCs cultured in the presence of TGF-beta3 in vitro and in vivo expressed high levels of aggrecan, cartilage oligomer matrix protein, SOX9, and type II collagen. However, a decrease in type I collagen expression was observed from 1 to 4 weeks in the presence of TGF-beta3. Moreover, histological and immunohistochemical assays revealed that large amounts of type II and proteoglycan were released from BMSCs embedded in fibrin constructs, while decreased levels of collagen type I were observed in BMSCs cultured in constructs that contained nanoparticles that were loaded with TGF-beta both in vitro and in vivo. These findings indicate that use of fibrin constructs that contained BMSCs and were provided with sustained levels of growth factors for a long period of time enabled the formation of hyaline cartilage tissue in vitro and in vivo. Overall, these results indicate that the system evaluated here may be useful for minimally invasive transplantation, BMSC differentiation, and engineering of composite tissue structures with multiple cellular phenotypes.

A Novel Double‐Network Hydrogel Induces Spontaneous Articular Cartilage Regeneration in vivo in a Large Osteochondral Defect

We have developed a novel method to induce spontaneous hyaline cartilage regeneration in vivo for a large osteochondral defect by implanting a plug made from a double-network hydrogel composed of poly(2-acrylamido-2-methylpropanesulfonic acid) and poly(N,N'-dimethylacrylamide) at the bottom of the defect, leaving the cavity vacant. In cells regenerated in the treated defect, type-2 collagen, Aggrican, and SOX9 mRNAs were highly expressed and the regenerated matrix was rich in proteoglycan and type-2 collagen at 4 weeks. This fact gave a significant modification to the commonly established concept that hyaline cartilage tissue cannot regenerate in vivo. This study prompted an innovative strategy in the field of joint surgery to repair an osteochondral defect using an advanced, high-function hydrogel.

Rotating three‐dimensional dynamic culture of adult human bone marrow‐derived cells for tissue engineering of hyaline cartilage

The method of constructing cartilage tissue from bone marrow-derived cells in vitro is considered a valuable technique for hyaline cartilage regenerative medicine. Using a rotating wall vessel (RWV) bioreactor developed in a NASA space experiment, we attempted to efficiently construct hyaline cartilage tissue from human bone marrow-derived cells without using a scaffold. Bone marrow aspirates were obtained from the iliac crest of nine patients during orthopedic operation. After their proliferation in monolayer culture, the adherent cells were cultured in the RWV bioreactor with chondrogenic medium for 2 weeks. Cells from the same source were cultured in pellet culture as controls. Histological and immunohistological evaluations (collagen type I and II) and quantification of glycosaminoglycan were performed on formed tissues and compared. The engineered constructs obtained using the RWV bioreactor showed strong features of hyaline cartilage in terms of their morphology as determined by histological and immunohistological evaluations. The glycosaminoglycan contents per microg DNA of the tissues were 10.01 +/- 3.49 microg/microg DNA in the case of the RWV bioreactor and 6.27 +/- 3.41 microg/microg DNA in the case of the pellet culture, and their difference was significant. The RWV bioreactor could provide an excellent environment for three-dimensional cartilage tissue architecture that can promote the chondrogenic differentiation of adult human bone marrow-derived cells.

Application of High-Mobility-Group-A Proteins Increases the Proliferative Activity of ChondrocytesIn Vitro

The low capability of self-repair in hyaline cartilage tissue and chondrocytes de-differentiating when grown in vitro (e.g., for tissue engineering approaches) limits articular cartilage repair. It has been shown that the embryonic architectural transcription factors of the high-mobility-group-A (HMGA) protein family affect the regulation of cell differentiation by influencing the state of cell chromatin and are involved in hyaline cartilage development by affecting the expression of chondrocyte-specific marker genes. Thus, the control of cartilage cell proliferation and differentiation by HMGA proteins promises to be an important aspect in cartilage tissue repair. To elucidate the effects on the proliferative activity of hyaline chondrocytes, HMGA proteins were recombinantly expressed, highly purified, and applied to porcine hyaline cartilage cells growing in in vitro monolayer cell culture. Direct application of HMGA1a, HMGA1b, and HMGA2 proteins onto porcine chondrocytes was shown to have a highly significant influence on cell proliferation. Greater proliferation of chondrocytes was achieved than in the untreated control group, indicating a promising approach to enhancing cartilage tissue repair.

Repair of prefabricated defects of articular cartilage by transplanting cultured masses of autologouschondrocytes

Objective To explore the feasibility of repairing defects of articular cartilage with cul-tured mass of autologous chondrocytes. Methods Forty-eight knees of 24 adult New Zealand rabbits were divided into blank control group, periosteum transplantation group and experiment group. A quadrate full-thickness cartilage defect was fabricated in each patellar grove of distal femur. In experiment group, cartilage was obtained from one of the shoulders in the same operation, and the chondrocytes were isolated from the cartilage tissue with type Ⅱ collagenase digestion and cultured and amplified in flasks in vitro. In a second surgery, masses of the autologous chondrocytes were implanted into the defects after debridement of the pre-fabricated defects. Finally the defect was sealed with a piece of periosteum obtained from the upper anterior tibia. The defects in blank control group were left untreated and in periosteum transplanted group were sealed only with periosteum. The animals were sacrificed in the 3rd and 6th months after the second operation re-spectively. Efficiency of repair was evaluated according to Wakaniti scoring and statistically analyzed with One-Way ANOVA and Scheffe test. Results In experiment group, 9 of the 11 defects were well repaired with mature hyaline cartilage tissue. However, 2 of the 11 defects were not repaired due to languishment of the cells implanted. In periosteum transplantation group, most of the defects were repaired only with thin fibro-cartilage or fibrous tissue. In blank control group, most of the defects were just filled with little fibrous tissue. Wakaniti scoring showed 3.82 points for experiment group, 6.71 for periosteum transplantation group and 9.23 for blank control group, with a significant difference (F=5.96, P=0.00). Conclusions It is a promising way of repairing the articular cartilage to conduct mass transplantation of cultured auto]ogous articular chondrocytes. The quality of repaired tissue is correlated with the activity of cells transplanted. Key words: Chondrocyte; Articular ; Rabbits

Osteochondritis dissecans of the elbow

Purpose of review Treatment of osteochondritis dissecans of the elbow remains challenging. Recently, several techniques for resurfacing a cartilaginous lesion with hyaline cartilage have been developed and applied to osteochondritis dissecans lesions. In this review, we mainly focus on the development of surgical management for osteochondritis dissecans of the elbow over the past year. Recent findings The surgical strategy for osteochondritis dissecans of the humeral capitellum (capitellar osteochondritis dissecans) has tended to shift from marrow-stimulating techniques to autologous osteochondral grafts as a cartilage-resurfacing technique. Osteochondral grafts for capitellar osteochondritis dissecans provide better outcomes than simple excision. Regarding the postoperative morbidity of the donor knee, no adverse effect on the donor site is found in young athletes with capitellar osteochondritis dissecans. Additionally, arthroscopic surgery for osteochondritis dissecans lesions has been expanded as well as for other elbow disorders. However, there has been no evidence that arthroscopic surgery for osteochondritis dissecans lesions results in any better prognosis for the patient. Summary The goal of treatment for capitellar osteochondritis dissecans is to return patients to their previous level of sport activities and to regenerate long-lasting hyaline cartilage tissue to replace cartilaginous lesions. For this treatment goal, an arthroscopic cartilage-resurfacing procedure may be an ideal treatment for capitellar osteochondritis dissecans.

Mesenchymal Chondrosarcoma of the Mandible

This report describes a 33-year-old man diagnosed with mesenchymal chondrosarcoma. The patient was referred with a painless, elastic hard mass in the retromolar region. Radiologically, the tumour presented as an expansion of the right mandibular ramus partly extending to the inferior masseter A segmental mandibulectomy was performed during the initial surgery. Histopathologically, the tumour showed well-differentiated hyaline cartilage tissue in the lobules with cartilaginous islands and small cells. Immunohistochemically, the tumour cells reacted positively to clusters of differentiation99 and S-100 protein. The tumour recurred in the right inferior temporal fossa 3 years after the initial surgery. Although radical right maxillectomy and dissection of the inferior temporal fossa were carried out immediately, the patient developed multiple pulmonary metastases after 10 months.

The Role of Progenitor Cells in Osteoarthritis

It remains a great challenge to enhance the regeneration potential of hyaline cartilage tissue. Tissue degeneration activities initiated after major injury or due to age-related processes override the generally limited self-renewal capacity of this tissue. Numerous catalytic enzymes lead to chondrocyte apoptosis and extracellular matrix deterioration. During early embryonic development, some of the embryonic stem cells of the inner cell mass of the blastocyst will turn into the mesoderm. This will be the founder of the mesenchymal cells in connective tissues of adult life, such as bone, tendon, muscle, and cartilage. Some of these embryonic mesenchymal cells are believed not to differentiate, but to reside in each of the tissues. These are now collectively described as adult mesenchymal stem cells, which are thought to be capable of repairing injured tissue. To date, various populations of bone marrow stroma cells, one of the various populations of adult stem cells, have been described and have been experimentally differentiated into cartilage tissue in vivo and in vitro. In this review, we will briefly summarize the current knowledge about stem cell related cells in cartilage tissue that are potentially involved in regeneration processes in osteoarthritis. Our unpublished results indicate that a cell population already present in the diseased cartilage tissue might be a starting point for a regenerative therapy for osteoarthritis.

Experimental studies of mechanically-induced articular cartilage defects following implantation of allogeneic embryonal chondrocytes in a collagen-fibrin gel in chickens

Full thickness defects (diameter 1,7 mm; depth 2,5 mm) were created mechanically in articular cartilage and subchondral bone of the condyles of tibiotarsal joints of 9-month old chickens. This full-thickness defects were repaired with cultured allogenic embryonic chick epiphyseal chondrocytes from the tibiae and femura of 10-days-old chicken embryos. The cells were embedded in a collagen-fibrinogen-matrix. Controls were similarly operated, but received either no treatment or implants the delivery substance only. Healing of the defects was observed macroscopically, histologically, histochemically and histomorphometrically after 3, 12 and 24 weeks. This graft was successfully transplanted in mechanically induced defects in 80%. The resulting hyaline cartilage was structurally reorganized according to the host pattern and under the influence of environmental conditions. The articular zone preserved it's cartilaginous phenotype, whereas the subchondral regions were transformed into bone. 12 weeks after the operation the defects in the experimental group were completely filled. In all instances in this group, there was an initial extreme increase of mitotic rate and cell number. After 24 weeks normal and subnormal values were founded. The defects in the control groups healed with fibrocartilage. Our results showed, that only the defects in the experimental group were completely filled with reparative hyaline cartilage tissue. In the present study the mixture of cultured allogenic embryonic chondrocytes and a collagen-fibrinogen-matrix was used successfully as a transplant for repairing defects in articular cartilage of chickens. Thus allogenic transplantation of cultured embryonal chondrocytes appears to be one of the most promising methods for the restoration of articular cartilage.

Cartilage T2 Assessment: Differentiation of Normal Hyaline Cartilage and Reparative Tissue after Arthroscopic Cartilage Repair in Equine Subjects

To prospectively assess T2 mapping characteristics of normal articular cartilage and of cartilage at sites of arthroscopic repair, including comparison with histologic results and collagen organization assessed at polarized light microscopy (PLM). Study protocol was compliant with the Canadian Council on Animal Care Guidelines and approved by the institutional animal care committee. Arthroscopic osteochondral autograft transplantation (OAT) and microfracture arthroplasty (MFx) were performed in knees of 10 equine subjects (seven female, three male; age range, 3-5 years). A site of arthroscopically normal cartilage was documented in each joint as a control site. Joints were harvested at 12 (n = 5) and 24 (n = 5) weeks postoperatively and were imaged at 1.5-T magnetic resonance (MR) with a 10-echo sagittal fast spin-echo acquisition. T2 maps of each site (21 OAT harvest, 10 MFx, 12 OAT plug, and 10 control sites) were calculated with linear least-squares curve fitting. Cartilage T2 maps were qualitatively graded as "organized" (normal transition of low-to-high T2 signal from deep to superficial cartilage zones) or "disorganized." Quantitative mean T2 values were calculated for deep, middle, and superficial cartilage at each location. Results were compared with histologic and PLM assessments by using kappa analysis. T2 maps were qualitatively graded as organized at 20 of 53 sites and as disorganized at 33 sites. Perfect agreement was seen between organized T2 and histologic findings of hyaline cartilage and between disorganized T2 and histologic findings of fibrous reparative tissue (kappa = 1.0). Strong agreement was seen between organized T2 and normal PLM findings and between disorganized T2 and abnormal PLM findings (kappa = .92). Quantitative assessment of the deep, middle, and superficial cartilage, respectively, showed mean T2 values of 53.3, 58.6, and 54.9 msec at reparative fibrous tissue sites and 40.7, 53.6, and 61.6 msec at hyaline cartilage sites. A significant trend of increasing T2 values (from deep to superficial) was found in hyaline cartilage (P < .01). Fibrous tissue sites had no significant change with depth (P > .59). Qualitative and quantitative T2 mapping helped differentiate hyaline cartilage from reparative fibrocartilage after cartilage repair at 1.5-T MR imaging.

Joint resurfacing using allograft chondrocytes embedded in alginate gel

To explore the feasibility of repairing the articular cartilage with allo-articular chondrocytes embedded in alginate gel. Allo-articular chondrocytes were isolated from three adult New zealand rabbits. The cells were cultured in DMEM/F-12 supplemented with 20% fetal bovine serum (FBS). Chondrocytes of 2nd - 3rd passage were harvested and were diluted to 5.0 x 10(7) cells/ml with 1.2% alginate. Then alginate gel was formed by 102 mM CaCl(2). The gels were cultured subsequently for 1 week and then transferred to the full-thickness defects in the femoral condyles of adult rabbits. In control group the defects were left untreated. The animals were sacrificed in the 3rd and 6th month after operation respectively. The specimens were decalcified with 50% formic acid. The histologic sections were stained with safranin O-fast green, hematoxylin-eosin (H&E) and picric acid-Sirius red and immunohisto-stained for type II collagen and aggrecan. The repairing efficiency was evaluated according to Wakitani scoring. In the experiment group all 8 defects acquired repair, 7/8 were repaired with mature hyaline cartilage tissue, and 1/8 was with fibrocartilage tissue for less cell-gel inputted. The thick of repaired tissues were closed to the normal and the tissue integrated smoothly with cartilage around the defects. Safranin O staining of the matrix acted in accordance with the normal and immunostaining for type II collagen and aggrecan showed positive. Picric acid-Sirius red staining showed that the chondrocytes lined in lines and the collagen aligned like Gothic architecture structure by polarization microscopy. There was no evidence of residue of alginate and inflammation in 3rd month specimens and no obvious deterioration at 6th month. But in control group, only a small amount of fibrous, fibrocartilage, or hyaline-like tissue was seen on the surface of the defects. Wakitani scoring showed 1.75 points for the experiment group and 7.65 for the control group. It is a promising way to repair the articular cartilage with homogeneous articular chondrocytes embedded in alginate gel.

Chondroid bone and secondary cartilage contribute to apical dentary growth in juvenile Atlantic salmon

The microstructure and tissue composition of the dentary bone in Atlantic salmon salmo salar parr were examined using a variety of histological and whole‐mount techniques. Proximally, the dentary is composed of typical cellular lamellar bone with Sharpey's fibres extending dorsally, proximally and ventrally. Meckel's cartilage is located medially through the entire length of the dentary, and degrades distally resulting in a short transitional zone between hyaline cartilage and connective tissue. At the distal tip of the dentary, isogenic clusters of chondrocytes of periosteal origin were observed secreting small amounts of pericellular cartilage matrix within the bone matrix. These characteristics are highly indicative of secondary chondrogenesis, and suggest that the apical part of the dentary bone in Atlantic salmon does not grow via‘pure’ intramembranous ossification, but rather via a modified mode of periosteal ossification involving secondary cartilage and chondroid bone. Furthermore, the unusual mode of gender‐related dentary growth (kype formation) in adult male Atlantic salmon could be the continuation of a general mode of salmonid apical dentary growth.

Ultrastructural analysis of mouse embryonic stem cell-derived chondrocytes

Pluripotent embryonic stem (ES) cells cultivated as cellular aggregates, so called embryoid bodies (EBs), differentiate spontaneously into different cell types of all three germ layers in vitro resembling processes of cellular differentiation during embryonic development. Regarding chondrogenic differentiation, murine ES cells differentiate into progenitor cells, which form pre-cartilaginous condensations in the EB-outgrowths and express marker molecules characteristic for mesenchymal cell types such as Sox5 and Sox6. Later, mature chondrocytes appear which express collagen type II, and the collagen fibers show a typical morphology as demonstrated by electron-microscopical analysis. These mature chondrogenic cells are organized in cartilage nodules and produce large amounts of extracellular proteoglycans as revealed by staining with cupromeronic blue. Finally, cells organized in nodules express collagen type X, indicating the hypertrophic stage. In conclusion, differentiation of murine ES cells into chondrocytes proceeds from the undifferentiated stem cell via progenitor cells up to mature chondrogenic cells, which then undergo hypertrophy. Furthermore, because the ES-cell-derived chondrocytes did not express elastin, a marker for elastic cartilage tissue, we suggest the cartilage nodules to resemble hyaline cartilage tissue.

Pedunculated Synovium Grafts in Articular Cartilage Defects in Rabbits

A rabbit model was used to assess the nature of healing tissues in hyaline cartilage defects and to compare the healing in defects treated with pedunculated synovium grafts to those in defects without synovial grafting. Both knees of 28 1-year-old rabbits were operated. A 3× 2-mm cartilage defect that exposed cancellous bone was created in the non-weight-bearing area of each medial femoral condyle. Each right-knee defect was covered with a pedunculated synovial graft obtained from the same joint, and the left-knee defects were left uncovered as controls. Groups of rabbits were sacrificed at 3, 6, 12, and 24 weeks postsurgery. Sections from each knee were stained with hematoxylin–eosin and safranin O—fast green staining, and were immunohistochemically stained for type II collagen. The healing at each site was histologically scored, and the intensity of staining for type II collagen was graded. At 12 and 24 weeks, statistical comparisons of histological scores revealed significantly more hyaline cartilage tissue in the synovium-grafted defects. At 24 weeks, these same defects showed significantly more type II collagen. Thus, pedunculated synovium transplantation appears to hold promise as a method for repairing hyaline cartilage defects.

QUANTIFICATION OF CHONDROCYTE MORPHOLOGY BY CONFOCAL ARTHROSCOPY

The purpose of this study was to determine the effectiveness of a novel Laser Scanning Confocal Arthroscope (LSCA) for the morphological quantification of articular cartilage chondrocytes. Healthy and debrided regions of the knee articular cartilage of six (6) New Zealand White rabbits were imaged during open follow-up surgery. Quantitative morphological analysis of chondrocyte cell populations was performed and compared to known parameters. Optical histology images were compared to conventional histology of similar sites. Optical histology revealed viable cells in normal hyaline cartilage tissue and enabled the visualization of fibro-cartilage in defect tissue. Morphological analysis was able to characterize the in vivo two-dimensional equivalent-area-diameter of chondrocytes. Significant differences (P&lt;0.05) were seen between the morphology of chondrocytes observed in optical and conventional histology. This study concludes that the LSCA is capable of illustrating the surface and sub-surface appearance of healthy and defect articular cartilage, thereby providing a non-destructive method for assessing cartilage condition in vivo. In this role the LSCA may find application in the investigation of cartilage pathologies or repair techniques.

Tissue engineering of biphasic cartilage constructs using various biodegradable scaffolds: an in vitro study

Biological restoration of osteochondral defects requires suitable subchondral support material that also allows the induction of hyaline cartilage tissue. Biphasic implants consisting of pre-fabricated neocartilage and an underlying biodegradable osteoconductive base may meet these requirements. Here we explore various candidate biodegradable support materials onto which neo-cartilage was produced in vitro. Porcine chondrocytes were seeded in a closed and static bioreactor with a base of biomaterial consisting of either poly- l-lactide [P( l)LA], poly- d,l-lactide [P( d, l)LA] or Collagen-hydroxyapatite [Col-HA] and were cultured for 15 weeks. Viable neo-cartilage was produced on each biomaterial with differing amounts of cellular colonisation. P( d,l)LA breakdown was more rapid and uneven among the three biomaterials, leading to constructs of irregular shape. Little or no breakdown or chondrocyte colonisation was evident in P( l)LA. Col-HA constructs were superior in terms of viability, implant morphology and integration between neo-cartilage and biomaterial. These results indicate that our reported system has potential for producing biphasic implants that may be adequate for the repair of osteochondral defects.