Poly(2-acrylamido-2-methylpropanesulfonic acid) gel induces articular cartilage regeneration in vivo: Comparisons of the induction ability between single- and double-network gels (original) (raw)

Influence of the gel thickness on in vivo hyaline cartilage regeneration induced by double-network gel implanted at the bottom of a large osteochondral defect: Short-term results

BMC Musculoskeletal Disorders, 2013

Background A double-network (DN) gel, which is composed of poly(2-acrylamido-2-methylpropanesulfonic acid) and poly(N,N’-dimethyl acrylamide), can induce hyaline cartilage regeneration in vivo in a large osteochondral defect. The purpose of this study was to clarify the influence of the thickness of the implanted DN gel on the induction ability of hyaline cartilage regeneration. Methods Thirty-eight mature rabbits were used in this study. We created an osteochondral defect having a diameter of 4.3-mm in the patellofemoral joint. The knees were randomly divided into 4 groups (Group I: 0.5-mm thick gel, Group II: 1.0-mm thick gel, Group III: 5.0-mm thick gel, and Group IV: untreated control). Animals in each group were further divided into 3 sub-groups depending on the gel implant position (2.0-, 3.0-, or 4.0-mm depth from the articular surface) in the defect. The regenerated tissues were evaluated with the Wayne’s gross and histological grading scales and real time PCR analysis of th...

Effects of culture on PAMPS/PDMAAm double-network gel on chondrogenic differentiation of mouse C3H10T1/2 cells: in vitro experimental study

BMC musculoskeletal disorders, 2014

Recently, several animal studies have found that spontaneous hyaline cartilage regeneration can be induced in vivo within a large osteochondral defect by implanting a synthetic double-network (DN) hydrogel, which is composed of poly-(2-acrylamido-2-methylpropanesulfonic acid) (PAMPS) and poly-(N,N'-dimethyl acrylamide) (PDMAAm), at the bottom of the defect. However, the effect of hydrogel on hyaline cartilage regeneration remains unexplained. The purpose of this study was to investigate the chondrogenic differentiation of C3H10T1/2 cells on PAMPS/PDMAAm DN gel. C3H10T1/2 cells of 1.0 × 105 were cultured on PAMPS/PDMAAm DN gel in polystyrene tissue culture dishes or directly on polystyrene tissue culture dishes. We compared cultured cells on PAMPS/PDMAAm DN gel with those on polystyrene dishes by morphology using phase-contrast microscopy, mRNA expression of aggrecan, type I collagen, type II collagen, Sox 9 and osteocalcin using real-time RT-PCR, and local expression of type II ...

Hyaluronic acid affects the in vitro induction effects of Synthetic PAMPS and PDMAAm hydrogels on chondrogenic differentiation of ATDC5 cells, depending on the level of concentration

BMC Musculoskeletal Disorders, 2013

Background It has been a common belief that articular cartilage tissue cannot regenerate in vivo. Recently, however, we have found that spontaneous hyaline cartilage regeneration can be induced in vivo by implanting a synthetic double-network (DN) hydrogel, which is composed of poly-(2-acrylamido-2-methylpropanesulfonic acid) (PAMPS) and poly-(N,N’-dimethyl acrylamide) (PDMAAm). However, the mechanism of this phenomenon has not been clarified. Recently, we have found that single-network PAMPS and PDMAAm gels can induce chondrogenic differentiation of ATDC5 cells in vitro even in a maintenance medium. In the in vivo condition, there is a strong possibility that the induction effect of the gel itself is enhanced by some molecules which exist in the joint. We have noticed that the joint fluid naturally contains hyaluronic acid (HA). The purpose of this study is to clarify in vitro effects of supplementation of HA on the differentiation effect of the PAMPS and PDMAAm gels. Methods We cu...

Gene expression profile of the cartilage tissue spontaneously regenerated in vivo by using a novel double-network gel: Comparisons with the normal articular cartilage

BMC Musculoskeletal Disorders, 2011

Background: We have recently found a phenomenon that spontaneous regeneration of a hyaline cartilage-like tissue can be induced in a large osteochondral defect by implanting a double-network (DN) hydrogel plug, which was composed of poly-(2-Acrylamido-2-methylpropanesulfonic acid) and poly-(N, N'-Dimetyl acrylamide), at the bottom of the defect. The purpose of this study was to clarify gene expression profile of the regenerated tissue in comparison with that of the normal articular cartilage. Methods: We created a cylindrical osteochondral defect in the rabbit femoral grooves. Then, we implanted the DN gel plug at the bottom of the defect. At 2 and 4 weeks after surgery, the regenerated tissue was analyzed using DNA microarray and immunohistochemical examinations. Results: The gene expression profiles of the regenerated tissues were macroscopically similar to the normal cartilage, but showed some minor differences. The expression degree of COL2A1, COL1A2, COL10A1, DCN, FMOD, SPARC, FLOD2, CHAD, CTGF, and COMP genes was greater in the regenerated tissue than in the normal cartilage. The top 30 genes that expressed 5 times or more in the regenerated tissue as compared with the normal cartilage included type-2 collagen, type-10 collagen, FN, vimentin, COMP, EF1alpha, TFCP2, and GAPDH genes. Conclusions: The tissue regenerated by using the DN gel was genetically similar but not completely identical to articular cartilage. The genetic data shown in this study are useful for future studies to identify specific genes involved in spontaneous cartilage regeneration.

In vivo cartilage regeneration induced by a double-network hydrogel: Evaluation of a novel therapeutic strategy for femoral articular cartilage defects in a sheep model

Journal of biomedical materials research. Part A, 2016

The purpose of this study was to establish the efficacy of a therapeutic strategy for an articular cartilage defect using a PAMPS/PDMAAm DN gel in a sheep model. Seventeen mature sheep were used in this study. We created a 6.0-mm osteochondral defect in the femoral trochlea of the patellofemoral (PF) joint and the medial condyle of the tibiofemoral (TF) joint. A cylindrical DN gel plug was implanted into the defect of the right knee so that a vacant space of the planned depths of 2.0 mm in Group I, 3.0 mm in Group II, and 4.0 mm in Group III were left. In the left knee, we created a defect with the same depth as the right knee. The regenerated tissues were evaluated with the O'Driscoll score and real time PCR analysis of the cartilage marker genes at 12 weeks. The DN-gel implanted defect of Group II in the PF and TF joints was completely filled with a sufficient volume of the proteoglycan-rich tissue stained with Safranin-O. The score showed that Group II was significantly great...

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

Journal of Materials Science: Materials in Medicine, 2011

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 12 weeks 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.

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

Macromolecular Bioscience, 2009

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 0dimethylacrylamide) 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.

Improved cartilage repair viain vitropre-maturation of MSC-seeded hyaluronic acid hydrogels

Biomedical Materials, 2012

Functional repair of focal cartilage defects requires filling the space with neotissue that has compressive properties comparable to native tissue and integration with adjacent host cartilage. While poor integration is a common complication with current clinical treatments, reports of tissue engineering advances in the development of functional compressive properties rarely include analyses of their potential for integration. Our objective was thus to assess both the maturation and integration of mesenchymal stem cell (MSC) laden hyaluronic acid (HA) hydrogels in an in vitro cartilage defect model. Furthermore, we considered the effects of an initial period of prematuration as well as various material formulations to maximize both construct compressive properties and integration strength. MSCs were encapsulated in 1%, 3%, and 5% methacrylated HA (MeHA) or 2% agarose (Ag) and gelled directly (in situ) within an in vitro cartilage defect or were formed and then pre-cultured for 4 weeks before implantation. Results showed the integration strength of pre-cultured repair constructs was equal to (1% MeHA) or greater than (2% Ag) the integration of in situ repaired cartilage. Moreover, MSC chondrogenesis and maturation was restricted by the in situ repair environment with constructs maturing to a much lesser extent than pre-matured constructs. These results indicate that construct pre-maturation may be an essential element of functional cartilage repair.

Implantation of Various Cell-Free Matrixes Does Not Contribute to the Restoration of Hyaline Cartilage within Full-Thickness Focal Defects

International Journal of Molecular Sciences, 2021

Articular cartilage is a highly organized tissue that has a limited ability to heal. Tissue engineering is actively exploited for joint tissue reconstruction in numerous cases of articular cartilage degeneration associated with trauma, arthrosis, rheumatoid arthritis, and osteoarthritis. However, the optimal scaffolds for cartilage repair are not yet identified. Here we have directly compared five various scaffolds, namely collagen-I membrane, collagen-II membrane, decellularized cartilage, a cellulose-based implant, and commercially available Chondro-Gide® (Geistlich Pharma AG, Wolhusen, Switzerland) collagen membrane. The scaffolds were implanted in osteochondral full-thickness defects, formed on adult Wistar rats using a hand-held cutter with a diameter of 2.0 mm and a depth of up to the subchondral bone. The congruence of the articular surface was almost fully restored by decellularized cartilage and collagen type II-based scaffold. The most vivid restoration was observed 4 mont...