Injectable Micelle-Incorporated Hydrogels for the Localized Chemo-Immunotherapy of Breast Tumors.

Although immune checkpoint blockade (ICB) holds potential for the treatment of various tumors, a considerable proportion of patients show a limited response to ICB therapy due to the low immunogenicity of a variety of tumors. It has been shown that some chemotherapeutics can turn low-immunogenic tumors into immunogenic phenotypes by inducing a cascade of immune responses. In this paper, we synthesized an injectable micelle-incorporated hydrogel, which was able to sequentially release the chemotherapeutic gemcitabine (GEM) and the hydrophobic indoleamine 2, 3-dioxygenase inhibitor, d-1-methyltryptophan (d-1MT) at tumor sites. The hydrogel was formed via the thiol-ene click reaction between the thiolated chondroitin sulfate and the micelle formed by amphiphilic methacrylated Pluronic F127, in which hydrophobic d-1MT was encapsulated in the core of the F127 micelles and the hydrophilic GEM was dispersed in the hydrogel network. The successive release of chemotherapeutics and immune checkpoint inhibitors at tumor tissues will first promote the infiltration of cytotoxic T lymphocytes and subsequently induce a robust antitumor immune response, ultimately exerting a synergetic therapeutic efficacy. In a 4T1 tumor-bearing mice model, our results showed that the combination of chemotherapy and immunotherapy through the micelle-incorporated hydrogel triggered an effective antitumor immune response and inhibited tumor metastasis to the lung. Our results highlight the potential of the injectable micelle-incorporated hydrogel for the localized chemo-immunotherapy in the treatment of breast tumors.

Subchronic toxicity evaluation of glucosamine and glucosamine in combination with chondroitin sulfate in obese Zucker rats.

D-glucosamine is a widely consumed dietary supplement used to promote joint health and treat osteoarthritis. It also stimulates intracellular hexosamine flux and increases transforming growth factor ß1 (TGFß1) mRNA expression and insulin resistance in animal studies. The effects of D-glucosamine exposure were investigated in obese Zucker rats. Male (leprfa/leprfa) Zucker rats were exposed to 30, 120, 300 and 600 mg D-glucosamine HCl per kg/day either alone or with chondroitin sulfate (24, 96, 240 and 480 mg/kg/day respectively) for 90 days. After 4 weeks exposure, these doses produced CmaxD-glucosamine concentrations of up to 24 µM in tail vein serum concurrent with a transient 30% increase in blood glucose concentration in the 600 mg/kg/day dose group. D-Glucosamine did not significantly alter body weight, blood glucose or serum insulin levels at any dose tested after 13 weeks exposure, but did increase urinary TGFß1 concentrations. The Zucker rats developed nephropathy and scrotal sores that were related to their hyperglycemia and obesity, and D-glucosamine exposure exacerbated these conditions to a small extent. The incidence of pulmonary osseous metaplasia was increased in rats exposed to D-glucosamine and a single incidence of adrenal osseous metaplasia was noted in one animal exposed to 600/480 mg D-glucosamine HCl/chondroitin sulfate. These lesions may have been treatment related. These studies suggest that the risk of adverse effects of oral D-glucosamine is small compared to that of hyperglycemia in these animals, but the potential for TGFß1-mediated pathologies, such as osseous metaplasia and renal nephropathy may be increased.

Chondroitin/dermatan sulfate purified from corb (Sciaena umbra) skin and bone: In vivo assessment of anticoagulant activity.

The present work deals with the extraction and purification of chondroitin sulfate/dermatan sulfate from skin (CSG) and bone (CBG) of corb (Sciaena umbra). Electrophoresis of these polymers in barium acetate buffer on cellulose acetate revealed two fractions similar to dermatan sulfate and chondroitin sulfate. The in vivo anticoagulant activity of both chondroitin sulfate/dermatan sulfate (CS/DS) were evaluated, at 25 and 75 mg kg-1 of body weight (b.w), using activated partial thromboplastin time (aPTT), prothrombine time (TT) and thrombin time (PT) tests. Results showed that aPTT of CSG and CBG at 75 mg kg-1 of b.w were prolonged by 1.59 and 1.48-fold respectively, compared with the control. Further, toxicity studies on liver performed by the catalytic activity of transaminases in plasma, oxidative stress markers and hepatic morphological changes demonstrated that CSG and CBG at both doses are not toxics. In summary, the higher activity and lower toxicity of both CS/DS, especially at 25 mg kg-1 of b.w, recommended these compounds as a better drug candidate.

Controlling methacryloyl substitution of chondroitin sulfate: injectable hydrogels with tunable long-term drug release profiles.

Drug delivery systems capable of local sustained release of small molecule therapeutics remain a critical need in many fields, including oncology. Here, a system to create tunable hydrogels capable of modulating the loading and release of cationic small molecule therapeutics was developed. Chondroitin sulfate (CS) is a sulfated glycosaminoglycan that has many promising properties, including biocompatibility, biodegradation and chemically modifiable groups for both covalent and non-covalent bonding. CS was covalently modified with photocrosslinkable methacryloyl groups (CSMA) to develop an injectable hydrogel fabrication. Utilizing anionic groups, cationic drugs can be adsorbed and released from the hydrogels. This study demonstrates the synthesis of CSMA with a varying degree of substitution (DS) to generate hydrogels with varying swelling properties, maximum injection force, and drug release kinetics. The DS of the synthesized CSMA ranged from 0.05 ± 0.02 (2 h reaction) to 0.28 ± 0.02 (24 h reaction) with a DS of 1 representing 100% modification. The altered DS resulted in changes in hydrogel properties with the swelling of 20% CSMA hydrogels ranging from 42 (2 h reaction) to 13 (24 h reaction) and injection forces ranging from 18 N (2 h reaction) to 94 N (24 h reaction). The release of sunitinib, an oncology therapeutic that inhibits intracellular signaling by targeting multiple receptor tyrosine kinases, ranged from 18 µg per day (2 h reaction) to 9 µg per day (24 h reaction). While decreasing the DS increased the hydrogel swelling and rate of therapeutic release, it also limited the hydrogel fabrication range to only those containing 10% or higher CSMA. Blended polymer systems with poly(vinyl alcohol)-methacrylate (PVAMA) were fabricated to stabilize the resulting hydrogels via attenuating the swelling properties. Release profiles previously unattainable with the pure CSMA hydrogels were achieved with the blended hydrogel formulations. Overall, these studies identify a method to formulate tunable CSMA and blended CSMA/PVAMA hydrogels capable of sustained release of cationic therapeutics over six weeks with applications in oncology therapeutics.

The synthesis of a new unsaturated derivative of chondroitin sulfate with increased antioxidant properties.

Chondroitin sulfate (CS) was regio-specifically modified to an unsaturated derivative (ΔCS) with a double bond in positions 4 and 5 of N-acetyl-d-galactosamine. The structure of ΔCS was elucidated in detail by two dimensional nuclear magnetic resonance, ultraviolet spectroscopy and mass spectrometry. The introduction of a nucleophilic CC double bond into a polymer backbone had no influence on biocompatibility of CS, which was demonstrated by MTT live-dead assay and enzymatic degradation in vitro. On the other hand the chemical modification significantly enhanced the reactivity of ΔCS towards numerous oxidizing agents, which might be promising for a variety of biomedical and cosmetic applications.

The Dietary Supplement Chondroitin-4-Sulfate Exhibits Oncogene-Specific Pro-tumor Effects on BRAF V600E Melanoma Cells.

Dietary supplements such as vitamins and minerals are widely used in the hope of improving health but may have unidentified risks and side effects. In particular, a pathogenic link between dietary supplements and specific oncogenes remains unknown. Here we report that chondroitin-4-sulfate (CHSA), a natural glycosaminoglycan approved as a dietary supplement used for osteoarthritis, selectively promotes the tumor growth potential of BRAF V600E-expressing human melanoma cells in patient- and cell line-derived xenograft mice and confers resistance to BRAF inhibitors. Mechanistically, chondroitin sulfate glucuronyltransferase (CSGlcA-T) signals through its product CHSA to enhance casein kinase 2 (CK2)-PTEN binding and consequent phosphorylation and inhibition of PTEN, which requires CHSA chains and is essential to sustain AKT activation in BRAF V600E-expressing melanoma cells. However, this CHSA-dependent PTEN inhibition is dispensable in cancer cells expressing mutant NRAS or PI3KCA, which directly activate the PI3K-AKT pathway. These results suggest that dietary supplements may exhibit oncogene-dependent pro-tumor effects.

Improved anticoagulant effect of fucosylated chondroitin sulfate orally administered as gastro-resistant tablets.

Fucosylated chondroitin sulfate (FucCS) is a potent anticoagulant polysaccharide extracted from sea cucumber. Its anticoagulant activity is attributed to the presence of unique branches of sulfated fucose. Although this glycosaminoglycan exerts an antithrombotic effect following oral administration, high doses are necessary to achieve the maximum effect. The diminished activity of FucCS following oral administration is likely due to its degradation in the gastrointestinal tract and its limited ability to cross the intestinal cell membranes. The latter aspect is particularly difficult to overcome. However, gastro-resistant tablet formulation may help limit the degradation of FucCS in the gastrointestinal tract. In the present work, we found that the oral administration of FucCS as gastro-resistant tablets produces a more potent and prolonged anticoagulant effect compared with its administration as an aqueous solution, with no significant changes in the bleeding tendency or arterial blood pressure. Experiments using animal models of arterial thrombosis initiated by endothelial injury demonstrated that FucCS delivered as gastro-protective tablets produced a potent antithrombotic effect, whereas its aqueous solution was ineffective. However, there was no significant difference between the effects of FucCS delivered as gastro-resistant tablets or as aqueous solution in a venous thrombosis model, likely due to the high dose of thromboplastin used. New oral anticoagulants tested in these experimental models for comparison showed significantly increased bleeding tendencies. Our study provides a framework for developing effective oral anticoagulants based on sulfated polysaccharides from marine organisms. The present results suggest that FucCS is a promising oral anticoagulant.

Purification, structural characterization and antiproliferative properties of chondroitin sulfate/dermatan sulfate from tunisian fish skins.

Chondroitin sulfate/dermatan sulfate GAGs were extracted and purified from the skins of grey triggerfish (GTSG) and smooth hound (SHSG). The disaccharide composition produced by chondroitinase ABC treatment showed the presence of nonsulfated disaccharide, monosulfated disaccharides ΔDi6S and ΔDi4S, and disulfated disaccharides in different percentages. In particular, the nonsulfated disaccharide ΔDi0S of GTSG and SHSG were 3.5% and 5.5%, respectively, while monosulfated disaccharides ΔDi6S and ΔDi4S were evaluated to be 18.2%, 59% and 14.6%, 47.0%, respectively. Capillary elecrophoresis analysis of GTSG and SHSG contained 99.2% and 95.4% of chondroitin sulfate/dermatan sulfate, respectively. PAGE analysis showed a GTSG and SHSG having molecular masses with average values of 41.72KDa and 23.8KDa, respectively. HCT116 cell proliferation was inhibited (p<0.05) by 70.6% and 72.65% at 200µg/mL of GTSG and SHSG respectively. Both GTSG and SHSG demonstrated promising antiproliferative potential, which may be used as a novel, effective agent.

Characterization and application of chondroitin sulfate/polyvinyl alcohol nanofibres prepared by electrospinning.

Composite nanofibres were prepared by electrospinning from a solution of chondroitin sulfate and polyvinyl alcohol. The chondroitin sulfate/polyvinyl alcohol (CS/PVA) mass ratios of 7/3 has a uniform and smooth morphology, and the average diameter of the nanofibres was 136nm. Combretastatin A-4 phosphate was loaded on the nanofibres and used as a model for testing drug release from the nanofibres crosslinked with glutaric dialdehyde. The morphology and structure of the nanofibres was determined using scanning electron microscopy. In order to assess their possible application to tissue engineering scaffolds, the toxicity and cytocompatibility of the nanofibres were tested by methylthiazolydiphenyl-tetrazolium bromide assay.

Synthesis and detection of N-sulfonated oversulfated chondroitin sulfate in marketplace heparin.

N-sulfonated oversulfated chondroitin sulfate (NS-OSCS), recently reported as a potential threat to the heparin supply, was prepared along with its intermediate derivatives. All compounds were spiked into marketplace heparin and subjected to United States Pharmacopeia (USP) identification assays for heparin (proton nuclear magnetic resonance [(1)H NMR], chromatographic identity, % galactosamine [%GalN], anti-factor IIa potency, and anti-factor Xa/IIa ratio). The U.S. Food and Drug Administration (FDA) strong-anionic exchange high-performance liquid chromatography (SAX-HPLC) method resolved NS-OSCS from heparin and OSCS and had a limit of detection of 0.26% (w/w) NS-OSCS. The %GalN test was sensitive to the presence of NS-OSCS in heparin. Therefore, current USP heparin monograph tests (i.e., SAX-HPLC and %GalN) detect the presence of NS-OSCS in heparin.

Injectable and Self-Healing Carbohydrate-Based Hydrogel for Cell Encapsulation.

With the fast development of cell therapy, there has been a shift toward the development of injectable hydrogels as cell carriers that can overcome current limitations in cell therapy. However, the hydrogels are prone to damage during use, inducing cell apoptosis. Therefore, this study was carried out to develop an injectable and self-healing hydrogel based on chondroitin sulfate multiple aldehyde (CSMA) and N-succinyl-chitosan (SC). By varying the CSMA to SC ratio, the hydrogel stiffness, water content, and kinetics of gelation could be controlled. Gelation readily occurred at physiological conditions, predominantly due to a Schiff base reaction between the aldehyde groups on CSMA and amino groups on SC. Meanwhile, because of the dynamic equilibrium of Schiff base linkage, the hydrogel was found to be self-healing. Cells encapsulated in the hydrogel remained viable and metabolically active. In addition, the hydrogel produced minimal inflammatory response when injected subcutaneously in a rat model and showed biodegradability in vivo. This work establishes an injectable and self-healing hydrogel derived from carbohydrates with potential applications as a cell carrier and in tissue engineering.

Multiorgan dysfunction syndrome secondary to joint supplement overdosage in a dog.

A 5-year-old spayed female Bernese mountain dog, with a chief complaint of vomiting and melena ingested approximately 200 nutritional joint supplement tablets. Despite aggressive therapy, the patient developed a coagulopathy, pancreatitis, peritonitis, acute kidney injury, and was euthanized. Postmortem examination revealed myocardial necrosis, pneumonia, centrilobular hemorrhage and necrosis of the liver, vasculitis, and acute tubular necrosis.

Syndrome de défaillance multiviscérale secondaire à un surdosage d'un supplément pour articulation chez un chien. Une chienne Bouvier bernois stérilisée âgée de 5 ans présentée avec une plainte principale de vomissements et de mélæna avait ingéré environ 200 comprimés de suppléments nutritionnels pour les articulations. Malgré une thérapie agressive, la patiente a développé une coagulopathie, une pancréatite, une péritonite et une blessure aiguë aux reins et a été euthanasiée. L'autopsie a révélé une nécrose du myocarde, une pneumonie, une hémorragie centrilobulaire et une nécrose du foie, une vasculite et une nécrose tubulaire.(Traduit par Isabelle Vallières).

Polyelectrolyte complexes of poly[(2-dimethylamino) ethyl methacrylate]/chondroitin sulfate obtained at different pHs: I. Preparation, characterization, cytotoxicity and controlled release of chondroitin sulfate.

For the first time, polyelectrolyte complex based on poly[(2-dimethylamino) ethyl methacrylate] (PDMAEMA) and chondroitin sulfate (CS) was prepared. The properties of novel material and precursors were investigated by WAXS, FTIR, TGA, SEM and DLS analysis. The PDMAEMA/CS PECs presented hydrophilic-hydrophobic transition at pHs 6.0, 7.0 and 8.0 whereas the non-complexed PDMAEMA showed such a transition at pH 8.0 and not at pHs 6.0 and 7.0. Studies of CS release from PECs at pHs 6 and 8 confirmed that the samples possess the potential to release the CS in alkaline and not in acidic conditions. Since PECs are thermo-responsive due to the reduction of LCST caused by the increase in pH, the release of CS was dependent on temperature and pH factors. Cytotoxicity assays using healthy VERO cells showed that the complexation between CS and PDMAEMA increased the PECs' biocompatibility related to PDMAEMA. However, the biocompatibility depends on the amount of CS present in the PECs.

Enhancing the intestinal absorption of low molecular weight chondroitin sulfate by conjugation with α-linolenic acid and the transport mechanism of the conjugates.

The purpose of this report was to demonstrate the effect of amphiphilic polysaccharides-based self-assembling micelles on enhancing the oral absorption of low molecular weight chondroitin sulfate (LMCS) in vitro and in vivo, and identify the transepithelial transport mechanism of LMCS micelles across the intestinal barrier. α-Linolenic acid-low molecular weight chondroitin sulfate polymers(α-LNA-LMCS) were successfully synthesized, and characterized by FTIR, (1)HNMR, TGA/DSC, TEM, laser light scattering and zeta potential. The significant oral absorption enhancement and elimination half-life (t1/2) extension of LNA-LMCS2 in rats were evidenced by intragastric administration in comparison with CS and LMCS. Caco-2 transport studies demonstrated that the apparent permeability coefficient (Papp) of LNA-LMCS2 was significantly higher than that of CS and LMCS (p<0.001), and no significant effects on the overall integrity of the monolayer were observed during the transport process. In addition, α-LNA-LMCS micelles accumulated around the cell membrane and intercellular space observed by confocal laser scanning microscope (CLSM). Furthermore, evident alterations in the F-actin cytoskeleton were detected by CLSM observation following the treatment of the cell monolayers with α-LNA-LMCS micelles, which further certified the capacity of α-LNA-LMCS micelles to open the intercellular tight junctions rather than disrupt the overall integrity of the monolayer. Therefore, LNA-LMCS2 with low cytotoxicity and high bioavailability might be a promising substitute for CS in clinical use, such as treating osteoarthritis, atherosclerosis, etc.

The copolymer of Poly(2-dimethylaminoethyl methacrylate) and methacrylated chondroitin sulfate with low cytotoxicity for gene delivery.

Poly(2-dimethylaminoethyl methacrylate) (PDMAEMA) is one of the most potent synthetic nonviral gene-delivery vectors because of its high transfection efficiency. However, the cytotoxicity of PDMAEMA is a major concern for its clinical applications. An anionic crosslinker is synthesized based on a natural polysaccharide, chondroitin sulfate (CS), by introducing methacrylate groups (CSMA). By systematically adjusting the substitution degree of methacrylation on CS and the weight percent of CSMA and PDMAEMA, sol-type copolymers are obtained as a gene-delivery vector. The combination of CS and PDMAEMA is expected not only to reduce the cytotoxicity of PDMAEMA, but also to facilitate better transfection efficiency than PDMAEMA because of the recognition of CS by CD44 receptors on cell surfaces. Two CSMA-modified PDMAEMA copolymers with different CSMA constituents are selected and their polyplexes prepared with plasmid DNA. The cytotoxicity and gene transfection efficiency of the polyplexes are tested and compared with those of PDMAEMA/pDNA. The copolymers of CSMA and PDMAEMA show significantly improved cell viability as compared with PDMAEMA. Their formed polyplexes with pDNA also show lower cytotoxicity than does PDMAEMA/pDNA. The transfection efficiency remarkably increases as the CSMA-modified PDMAEMA/pDNA polyplex is prepared at a weight ratio of 2.4. The internalization mechanism of CSMA-modified PDMAEMA/pDNA in HEK 293T cells is mainly based on caveolae-mediated endocytosis. However, both caveolae-mediated and CD44-mediated endocytosis mechanisms are involved in U87 cells.

Silver sulfadiazine loaded chitosan/chondroitin sulfate films for a potential wound dressing application.

Silver sulfadiazine (AgSD) loaded chitosan/chondroitin sulfate (CHI/CS) films were formed to be applied as a potential wound dressing material. The liquid uptake capacity of both, CHI/CS and CHI/CS/AgSD, films exhibited a pH-dependent behavior. Tensile tests showed that the amount of CS used to form the films and the further incorporation of AgSD affect the mechanical properties of the films. In vitro AgSD-release assays showed that the CHI/CS mass ratio influences the AgSD release rate. All the investigated CHI/CS/AgSD films sustain the AgSD release up to 96h at physiological pH. Antibacterial activity and cell viability assays showed that all the CHI/CS/AgSD films have activity against Pseudomonas aeruginosa and Staphylococcus aureus but they were not toxic to Vero cells. The results presented in this work indicate that the CHI/CS/AgSD exhibits potential to be applied as a wound dressing material.

Preparation and evaluation of nanoparticles for directed tissue engineering.

Herein we describe the preparation of a nanoparticulate system formed from an RGD-functionalized chitosan derivative by complexation with chondroitin sulfate. These bioactive complexes were developed to promote wound healing by inducing adhesion and subsequently migration of skin cells. The particles were characterized for their size, surface charge, stability and shape. Briefly, the nanoparticles were found to be stable up to 7 days in water at a diameter of 150-200 nm and a positive charge of 20 mV. In physiological media the particles swell significantly but remain intact. Tested in an in vitro cell model of human dermal fibroblasts, the particles were shown to promote cell adhesion and induce spreading in human dermal fibroblasts. The mean surface area per cell was found to be increased by three-fold (n=3 assays, p<0.01), for the cells plated on particles exposing RGD-peptides when compared to cells on control particles. This indicates a stimulation of the cells due to the exposure of the bioactive RGD-moieties and an enhanced cell-biomaterial interaction. Using nanoparticles is a novel approach to direct cellular behavior with numerous possible applications in tissue engineering such as substrate for dermal and epithelial cells, injectable suspensions or as building blocks to form scaffolds.

Combination of chondroitin sulfate and polyplex micelles from Poly(ethylene glycol)-poly{N'-[N-(2-aminoethyl)-2-aminoethyl]aspartamide} block copolymer for prolonged in vivo gene transfection with reduced toxicity.

Nonviral polycation-based gene carriers (polyplexes) have attracted attention as safe and efficient gene delivery systems. Polyplex micelles comprised of poly(ethyleneglycol)-block-poly{N'-[N-(2-aminoethyl)-2-aminoethyl]aspartamide} (PEG-PAsp(DET)) and plasmid DNA (pDNA) have shown high transfection efficiency with low toxicity due to the pH-sensitive protonation behavior of PAsp(DET), which enhances endosomal escape, and their self-catalytic degradability under physiological conditions, which reduces cumulative toxicity during transfection. In this study, we improved the safety and transfection efficiency of this polyplex micelle system by adding an anionic polycarbohydrate, chondroitin sulfate (CS). A quantitative assay for cell membrane integrity using image analysis software showed that the addition of CS markedly reduced membrane damage caused by free polycations in the micelle solution. It also reduced tissue damage and subsequent inflammatory responses in the skeletal muscle and lungs of mice following in vivo gene delivery with the polyplex micelles. Subsequently, this led to prolonged transgene expression in the target organs. This combination of polyplex micelles and CS holds great promise for safe and efficient gene introduction in clinical settings.

Structure elucidation and biological activity of the oversulfated chondroitin sulfate contaminant in Baxter heparin.

From late December 2007 to February 2008, the number of adverse responses to heparin infusions rose noticeably above baseline levels in North America, ultimately resulting in a widespread recall of all heparin vial products made by Baxter Healthcare. Using various analytical techniques and the de novo synthesis of a fully sulfated chondroitin sulfate (FSCS) derivative, the authors have confirmed the identity of the contaminant as an oversulfated chondroitin sulfate (OSCS) and have also defined the heterogeneity and concentration of this contaminant in various lots of heparin. Using both contaminated heparin products and the synthetically produced derivative, the authors have shown that the OSCS produces a dose-dependent hypotension in both pigs and rats and that the response in rats can be abrogated with bradyzide, a rodent-selective B(2) bradykinin receptor antagonist. The no observed effect level (NOEL) for this contaminant appears to be approximately 1 mg/kg, corresponding to a contamination level in finished lots of heparin of approximately 3%. Using human plasma, the OSCS derivative was shown to activate kallikrein. These data provide insight into the etiology of the adverse events, particularly refractory hypotension, observed in patients who were exposed to heparin contaminated with OSCS.

The application of type II collagen and chondroitin sulfate grafted PCL porous scaffold in cartilage tissue engineering.

This study investigates a poly(epsilon-caprolactone)-graft-type II collagen-graft-chondroitin sulfate (PCL-g-COL-g-CS) biomaterial as a scaffold for cartilage tissue engineering. Biodegradable polyester, PCL, was utilized to fabricate three-dimensional (3D) porous scaffolds by particulate leaching. The PCL scaffold was then surface modified by chemical bonding of 1,6-hexanediamine and the grafting of a bioactive polymer layer of COL and CS with the help of 1-ethyl-3-(3-dimethyl- aminopropyl) carbodiimide (EDC)/N-hydroxysuccinimide (NHS) on the modified PCL surface to produce PCL-g-COL and PCL-g-COL-g-CS, respectively. The characteristics of these modified and grafted matrices were examined by ESCA, aminolysis, collagen and CS assay, porosity and water-binding capacity. Grafted COL and CS markedly increased water-binding capacity, and promoted the spreading and growth of chondrocytes. During a 4-week culture period, PCL-g-COL and PCL-g-COL-g-CS matrices both provided more cell proliferation, as determined by measuring the DNA assay. Additionally, a larger amount of secreted collagen and glycosaminoglycans (GAGs) appeared in the PCL-g-COL-g-CS matrices than in the control (PCL) as indicated by the histochemical sections via Hematoxylin and eosin (H&E) stain, Masson trichrome stain and Safranin-O stain. The chondrocytes were induced to function normally; the cell phenotype was maintained, and the GAGs and collagen in the PCL-g-COL-g-CS scaffold were secreted in vitro. These results serve as a basis for future studies of the fabrication process and reveal the potential biocompatibility of the biomimetic matrix for regenerating articular cartilage or other organs.