No abstract available.
Chondrogenesis* ; Ear*

This study was intended to compare the cranial base morphology between the mandibular prognathism and maxillary retrognathism in skeletal class III patients. The subject of the present study was composed of 88 patients divided into two groups; Group 1 (Skeletal Class III with mandibular prognathism. SNA within normal range, SNB over normal range, n=54) and Group 2(Skeletal Class III with maxillary retrognathism. SNA below normal range, SNB within normal range, n=34). Lateral cephalogram were taken immediate before surgery and 18 landmarks were used to analyze the characteristics of cranial base and maxillomandibular skeleton. The result revealed that cranial base angle is significantly smaller in Group 1 than Group 2, which implies the influence of the cranial base angulation on the mandibular position. However the posterior cranial base length did not influence the mandibular horizontal position and anterior cranial base length did not influence the maxillary horizontal position. As the anterior cranial base length was closely related with ramal height, it is recommendable to investigate the regulatory mechanism of chondrogenesis of cranial base and condyle cartilage in the future research.
Cartilage ; Chondrogenesis ; Humans ; Prognathism* ; Reference Values ; Retrognathia* ; Skeleton ; Skull Base*

BACKGROUND: Articular cartilage lesions occur frequently but unfortunately damaged cartilage has a very limited intrinsic repair capacity. Therefore, there is a high need to develop technology that makes cartilage repair possible. Since joint damage will lead to (sterile) inflammation, development of this technology has to take into account the effects of inflammation on cartilage repair. METHODS: A literature search has been performed including combinations of the following keywords; cartilage repair, fracture repair, chondrogenesis, (sterile) inflammation, inflammatory factors, macrophage, innate immunity, and a number of individual cytokines. Papers were selected that described how inflammation or inflammatory factors affect chondrogenesis and tissue repair. A narrative review is written based on these papers focusing on the role of inflammation in cartilage repair and what we can learn from findings in other organs, especially fracture repair. RESULTS: The relationship between inflammation and tissue repair is not straightforward. Acute, local inflammation stimulates fracture repair but appears to be deleterious for chondrogenesis and cartilage repair. Systemic inflammation has a negative effect on all sorts of tissue repair. CONCLUSION: Findings on the role of inflammation in fracture repair and cartilage repair are not in line. The currently widely used models of chondrogenesis, using high differentiation factor concentrations and corticosteroid levels, are not optimal. To make it possible to draw more valid conclusions about the role of inflammation and inflammatory factors on cartilage repair, model systems must be developed that better mimic the real conditions in a joint with damaged cartilage.
Cartilage ; Cartilage, Articular ; Chondrogenesis ; Cytokines ; Immunity, Innate ; Inflammation ; Joints ; Macrophages

To study the cartilage differentiation of mouse mesenchymal stem cells (MSCs) induced by cartilage-derived morphogenetic proteins-2 in vitro, the MSCs were isolated from mouse bone marrow and cultured in vitro. The cells in passage 3 were induced into chondrogenic differentiation with different concentrations of recombinant human cartilage-derived morphogenetic proteins-2 (0, 10, 20, 50 and 100 ng/mL). After 14 days of induction, morphology of cells was observed under phase-contrast microscope. Collagen II mRNA and protein were examined with RT-PCR, Western blotting and immunocytochemistry respectively and the sulfate glycosaminoglycan was measured by Alcian blue staining. RT-PCR showed that CDMP-2 could promote expression of collagen II mRNA in an dose-dependant manner, especially at the concentration of 50 ng/mL and 100 ng/mL. Immunocytochemistry and Western blotting revealed a similar change. Alcian blue staining exhibited deposition of typical cartilage extracellular matrix. Our results suggest that mouse bone marrow mesenchymal stem cells can differentiate into chondrogenic phonotype with the induction of CDMP-2 in vitro, which provides a basis for further research on the role of CDMP-2 in chondrogenesis.
Bone Marrow Cells/*cytology ; Bone Morphogenetic Proteins/*pharmacology ; Cell Differentiation/*drug effects ; Cells, Cultured ; Chondrocytes/*cytology ; Chondrogenesis/drug effects ; Chondrogenesis/physiology ; Mesenchymal Stem Cells/*cytology ; Recombinant Proteins/pharmacology

OBJECTIVES: Recent basic science studies continue to further our understanding of the fundamental mechanisms that likely underlie the therapeutic benefits of hyaluronan derivatives. The purpose of this study is to elucidate the effects of hyaluronan on ATDC5 proliferation and differentiation. METHODS: ATDC5 cells derived from mouse teratocarcinoma have the capacity to differentiate along a number of connective tissue pathways and are an attractive source of chondrocyte precursor cells. In this study, hyaluronan influencing ATDC5 chondrogenesis were investigated using an bone block culture system. The cell proliferation was analyzed by MTT assay. To validate ATDC5 differentiation we studied ALP activity, collagen content and western blot of Hsp40. RESULTS: In cell proliferation, ATDC5 cells didn't show significant difference between controls and hyaluronan-treated cultures. But hyaluronan induced ALP activity and increased collagen accumulation. Hyaluronantreated ATDC5 cells expressed Hsp40 mRNA and protein within 24 hours. CONCLUSIONS: Hyaluronan-induced chondrogenic differentiation was not associated with ATDC5 cell proliferation. Hyaluronan-induced Hsp40 in cells can protect the cell function from damaged protein. These data provide new insights into regulatory mechanism defining pharmacological effects of hyaluronan.
Animals ; Blotting, Western ; Cell Proliferation ; Chondrocytes* ; Chondrogenesis ; Collagen ; Connective Tissue ; Hyaluronic Acid* ; Mice ; RNA, Messenger ; Teratocarcinoma

Over the past few years, considerable progress has been achieved about the extracellular elements and intracellular regulatory molecules that are involved in the regulation of chondrogenesis. However, little is known about the molecular mechanism of how these molecules influence the gene activities during cartilage differentiation. Recently we isolated a Chicken Cartilage derived Matrix Protein (CCMP 10), a novel protein, from chicken prechondrogenic mesenchyme. To further understand the function of CCMP-10 in cartilage development, we investigated the expression of CCMP-10 during the prechondrocyte differentiation in chick embryos and micromass cultured prechondrogenic cells, using a variety of methods such as transient transfection of CCMP 10, immunohistochemical localization, northern analysis, and western analysis. When transiently transfected, CCMP 10 was expressed in both nucleus and cytoplasm, with stronger intensity in the nucleus. In an immunohistochemical study, CCMP 10 was expressed in prechondrogeinc mesenchymal cell, perichondrium, and resting and proliferative zone of the growth plate of long bone, while no expression of CCMP 10 was observed in upper mature chondrocytes and hypertrophic chondrocytes. Northern analysis of micromass cultured prechondrogenic cells showed the expression of CCMP-10 mRNA for first 2 days, while Col 2a1, aggrecan, and CMP mRNAs, known genes to express in mature chondrocyte, initiated the expression at day 2 and continued to express by day 5. In western analysis, CCMP-10 was detected at initial stage and continued to express by day 3, while Col 2al protein began to express only one day after, and continued to express. Taken together, our data suggest that CCMP-10 may play a significant role in the early cartilage development.
Aggrecans ; Animals ; Cartilage* ; Chick Embryo ; Chickens* ; Chondrocytes ; Chondrogenesis* ; Cytoplasm ; Growth Plate ; Mesoderm ; RNA, Messenger ; Transfection

The purpose of this study is to investigate the effect of artificial dermis(Terudermis(R)) on cartilage induction from perichondrium. A total of 24 rabbits were used and divided into control(n = 12) and experimental groups(n = 12). Each group was divided into 2 weeks(n = 6) and 4 weeks subgroups(n = 6). The dorsal skin of the rabbit ear was incised in reverse L-shape and the perichondrium was exposed. The silicone membrane from the Terudermis(R) , 1 x 1 cm sized,was removed. The Terudermis(R) was grafted on the exposed perichondrium in the experimental group. However, Terudermis(R) was not grafted in the control group. At 2 and 4 weeks after the surgery, the specimen was obtained and studied by histologic study. The results are as follows: 1. In control group at 2 weeks after surgery, the appearance of perichondrocytes and chondrocytes were not different from those of normal tissue. 2. In control group at 4 weeks after surgery, the extent of chondroblast differentiation and cartilage regeneration was insignificant compared to experimental group. 3. In experimental group at 2 weeks after surgery, we examined the active differentiation process of chondroblast beneath the perichondrium. The mean thickness of the neocartilage layer was 0.11+/-0.04 mm. 4. In experimental group at 4 weeks after surgery, there was an active regenerated new cartilage layer eneath the perichondrium, but the neocartilage layer was immature. The mean thickness of neocartilage layer was 0.33+/-0.10 mm. In conclusion, this study suggested that the grafted Terudermis(R) has an effect on chondrogenetic induction by activating the perichondrium.
Cartilage ; Chondrocytes ; Chondrogenesis* ; Dermis* ; Ear ; Membranes ; Rabbits ; Regeneration ; Silicones ; Skin ; Transplants

PURPOSE: Articular cartilage is under continuous mechanical stresses during daily activity. The mechanical force must also be applied during the culturing process to produce a phenotypically correct tissue. We have developed bioreactor, capable to apply the three main fluid-induced stresses: shear stress, compression, and hydrostatic pressure. The objective of this study was to investigate the effects of bioreactor on chondrocyte proliferation and matrix synthesis in articular chondrocytes and to determine the most appropiate chondrogenesis biomechanical environment. MATERIALS AND METHODS: Articular cartilage was harvested from the rabbit knee. Isolated chondrocytes from articular cartilage were cultured in static culture and bioreactor culture. Bioreactor culture condition was fluid rate of 0.2 cm/sec and shear stress of 0.6x10-3 dyn/cm2 After 3 days, the effects of fluid-induced shear stress were evaluated by measuring the cell proliferation, observation of cell morphology and expression of cartilage specitic ECM using Histology, and Immunocytochemistrical staining. RESULTS: We have developed bioreactor and subjected chondrocytes to fluid-induced shear stress of 0.6x10-3 dyn/cm2 for 3 days. We observed changes in chondrocyte shape, orientation, and nodule formation. In metabolic studies, the application of fluid-induced shear stress to articular chondrocytes resulted in a significant increase in the proliferation of chondrocytes and the synthesis of type II collagen compared to that of in the static culture. CONCLUSION: From these results, it was concluded that the bioreactor which we developed produced appropriate chondrogenesis biomechanical environment.
Bioreactors* ; Cartilage ; Cartilage, Articular ; Cell Proliferation ; Chondrocytes ; Chondrogenesis ; Collagen Type II ; Hydrostatic Pressure ; Knee ; Stress, Mechanical

For the cartilage repair, the cell sources currently adopted are primarily chondrocytes or mesenchymal stem cells (MSCs). Due to the fact that chondrocytes dedifferentiate during 2-dimensional (2D) expansion, MSCs are generally more studied and considered to have higher potential for cartilage repair purposes. Here we question if the dedifferentiated chondrocytes can regain the chondrogenic potential, to find potential applications in cartilage repair. For this we chose chondrocytes at passage 12 (considered to have sufficiently dedifferentiated) and the expression of chondrogenic phenotypes and matrix syntheses were examined over 14 days. In particular, the chondrogenic potential of MSCs was also compared. Results showed that the dedifferentiated chondrocytes proliferated actively over 14 days with almost 2.5-fold increase relative to MSCs. Moreover, the chondrogenic ability of chondrocytes was significantly higher than that of MSCs, as confirmed by the expression of a series of mRNA levels and the production of cartilage extracellular matrix molecules in 2D-monolayer and 3-dimensional (3D)-spheroid cultures. Of note, the significance was higher in 3D-culture than in 2D-culture. Although more studies are needed such as the use of different cell passages and human cell source, and the chondrogenic confirmation under in vivo conditions, this study showing that the dedifferentiated chondrocytes can also be a suitable cell source for the cell-based cartilage repair, as a counterpart of MSCs, will encourage further studies regarding this issue.
Animals ; Cartilage ; Chondrocytes* ; Chondrogenesis ; Extracellular Matrix ; Humans ; Mesenchymal Stromal Cells ; Phenotype ; Rats* ; RNA, Messenger

Coculture between mesenchymal stem cells (MSCs) and chondrocytes has significant implications in cartilage regeneration. However, a conclusive understanding remains elusive. Previously, we reported that rabbit bone marrow-derived MSCs (rbBMSCs) could downregulate the differentiated phenotype of rabbit articular chondrocytes (rbACs) in a non-contact coculture system for the first time. In the present study, a systemic investigation was performed to understand the biological characteristics of chondrocytes in coculture with MSCs. Firstly, cells (MSCs and chondrocytes) from different origins were cocultured in transwell system. Different chondrocytes, when cocultured with different MSCs respectively, consistently demonstrated stimulated proliferation, transformed morphology and declined glycosaminoglycan secretion of chondrocytes. Next, cell surface molecules and the global gene expression of rbACs were characterized. It was found that cocultured rbACs showed a distinct surface molecule profile and global gene expression compared to both dedifferentiated rbACs and rbBMSCs. In the end, cocultured rbACs were passaged and induced to undergo the chondrogenic redifferentiation. Better growth and chondrogenesis ability were confirmed compared with control cells without coculture. Together, chondrocytes display comprehensive changes in coculture with MSCs and the cocultured rbACs are beneficial for cartilage repair.
Cartilage ; Chondrocytes ; Chondrogenesis ; Coculture Techniques ; Gene Expression ; Mesenchymal Stromal Cells ; Phenotype ; Population Characteristics ; Regeneration