scholarly journals Numerical Simulation of Electroactive Hydrogels for Cartilage–Tissue Engineering

Materials ◽  
2019 ◽  
Vol 12 (18) ◽  
pp. 2913 ◽  
Author(s):  
Abdul Razzaq Farooqi ◽  
Julius Zimmermann ◽  
Rainer Bader ◽  
Ursula van Rienen

The intrinsic regeneration potential of hyaline cartilage is highly limited due to the absence of blood vessels, lymphatics, and nerves, as well as a low cell turnover within the tissue. Despite various advancements in the field of regenerative medicine, it remains a challenge to remedy articular cartilage defects resulting from trauma, aging, or osteoarthritis. Among various approaches, tissue engineering using tailored electroactive scaffolds has evolved as a promising strategy to repair damaged cartilage tissue. In this approach, hydrogel scaffolds are used as artificial extracellular matrices, and electric stimulation is applied to facilitate proliferation, differentiation, and cell growth at the defect site. In this regard, we present a simulation model of electroactive hydrogels to be used for cartilage–tissue engineering employing open-source finite-element software FEniCS together with a Python interface. The proposed mathematical formulation was first validated with an example from the literature. Then, we computed the effect of electric stimulation on a circular hydrogel sample that served as a model for a cartilage-repair implant.

Biomaterials ◽  
2006 ◽  
Vol 27 (14) ◽  
pp. 2882-2889 ◽  
Author(s):  
Dirk Barnewitz ◽  
Michaela Endres ◽  
Ina Krüger ◽  
Anja Becker ◽  
Jürgen Zimmermann ◽  
...  

2021 ◽  
Vol 11 (17) ◽  
pp. 7821
Author(s):  
Angeliki Dimaraki ◽  
Pedro J. Díaz-Payno ◽  
Michelle Minneboo ◽  
Mahdiyeh Nouri-Goushki ◽  
Maryam Hosseini ◽  
...  

The treatment of articular cartilage defects remains a significant clinical challenge. This is partially due to current tissue engineering strategies failing to recapitulate native organization. Articular cartilage is a graded tissue with three layers exhibiting different cell densities: the superficial zone having the highest density and the deep zone having the lowest density. However, the introduction of cell gradients for cartilage tissue engineering, which could promote a more biomimetic environment, has not been widely explored. Here, we aimed to bioprint a scaffold with different zonal cell densities to mimic the organization of articular cartilage. The scaffold was bioprinted using an alginate-based bioink containing human articular chondrocytes. The scaffold design included three cell densities, one per zone: 20 × 106 (superficial), 10 × 106 (middle), and 5 × 106 (deep) cells/mL. The scaffold was cultured in a chondrogenic medium for 25 days and analyzed by live/dead assay and histology. The live/dead analysis showed the ability to generate a zonal cell density with high viability. Histological analysis revealed a smooth transition between the zones in terms of cell distribution and a higher sulphated glycosaminoglycan deposition in the highest cell density zone. These findings pave the way toward bioprinting complex zonal cartilage scaffolds as single units, thereby advancing the translation of cartilage tissue engineering into clinical practice.


2020 ◽  
Author(s):  
Mingjing Li ◽  
Fan Li

Abstract BackgroundArticular cartilage has limited self-repair ability. Tissue engineering is considered to be one of the most promising therapeutic approaches. Chitosan (CS) based hydrogels are the most widely used scaffolds which still need improvement. The purpose of this study was to investigate the efficacy of a thermally triggered injectable chitosan / type II collagen / polylactic acid / sodium β-glycerophosphate (CS/Col/PLA/GP) hydrogel and bone marrow mesenchymal stem cells (BMSCs) for the treatment of cartilage defects in rabbit knee joints. Material/MethodsThe CS-based hydrogels consisting of CS, Col II, PLA and GP were fabricated by chemical cross-linking method. The gel forming time and elastic modulus of these hydrogels were measured. We tested the viability, proliferation and differentiation of rabbit BMSCs cultured in the hydrogels by fluorescence staining, CCK-8 and PCR method. The hydrogels combined with or without BMSCs were injected into cartilage defects in rabbit knee joints and the materials were collected at 8 weeks after surgery. The repair effect of cartilage defects was evaluated based on gross observation, HE, safranin O and immunohistochemical staining. ResultsThe CS/Col/PLA/GP hydrogel was liquid at room temperature and gelled after 7.5±0.41min at 37°C. CS/Col /PLA/GP hydrogel had a modulus of 8.90 ± 0.12 kPa while CS/GP and CS/Col/GP hydrogels had the modulus of 4.07 ± 0.24 kPa and 4.93 ± 0.09 kPa. The results of Live/Dead cell viability assay reveal that most of BMSCs remained alive in the hydrogels. CCK-8 assay shows that the number of cells in CS/Col /PLA/GP hydrogel was significantly higher in comparison to the other groups on days 2 and 3 of cell culture (p<0.05). Aggrecan mRNA expression in the CS/Col /PLA/GP gel was the highest (p<0.05). Sox9 mRNA expression in the CS/Col /GP group was the highest, in which CS/Col /PLA/GP hydrogel was higher than the CS/GP hydrogel(p<0.05). Furthermore, CS/Col/PLA/GP and CS/Col /GP hydrogels showed higher COL2A1 mRNA expression in comparison to CS/GP constructs (p<0.05). In vivo studies showed that approximately 90% of the cartilage defects of rabbits treated by the hydrogel and BMSCs were repaired with hyaline-like tissue without obvious inflammation response. HE, safranin O, and immunohistochemical staining showed that the hyaline like cartilage was formed in cartilage defects, and the collagen content in the new generated cartilage was similar to the normal cartilage. The neocartilage was thinner than the surrounding normal cartilage, but it exhibited integration with adjacent healthy tissue. The abundant well-defined chondrocytes were aligned in several apparent chondrocyte clusters in the new generated cartilage.ConclusionsThe thermo-sensitive injectable CS/Col/PLA/GP composite hydrogel has better ability to promote survive, proliferation and chondrogenic differentiation of seeded BMSCs as compared against CS/Col/GP and CS/GP hydrogels. Combined with BMSCs to repair cartilage defects of rabbit knee joints, they can effectively reduce the cartilage defect area, and the new generated cartilage is comparable to normal cartilage structure. In addition, abundant availability and simple fabrication process also make CS/Col/PLA/GP composite hydrogel a suitable candidate scaffold in cartilage tissue engineering.


2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Jan-Philipp Stromps ◽  
Nora Emilie Paul ◽  
Björn Rath ◽  
Mahtab Nourbakhsh ◽  
Jürgen Bernhagen ◽  
...  

According to data published by the Centers for Disease Control and Prevention, over 6 million people undergo a variety of medical procedures for the repair of articular cartilage defects in the U.S. each year. Trauma, tumor, and age-related degeneration can cause major defects in articular cartilage, which has a poor intrinsic capacity for healing. Therefore, there is substantial interest in the development of novel cartilage tissue engineering strategies to restore articular cartilage defects to a normal or prediseased state. Special attention has been paid to the expansion of chondrocytes, which produce and maintain the cartilaginous matrix in healthy cartilage. This review summarizes the current efforts to generate chondrocytes from adipose-derived stem cells (ASCs) and provides an outlook on promising future strategies.


Author(s):  
Yu. B. Basok ◽  
V. I. Sevastianov

Some of the most pressing health problems of the industrial society are the damage and degeneration of articular cartilage associated with the limited capacity of tissues to regenerate. The review describes the existing and developing technologies for the recovery and replacement of damaged joint cartilage tissue. The results obtained are analyzed covering two major areas: the stimulation of regeneration of damaged cartilage tissue and the growing of cartilage tissue elements in bioreactors.


Author(s):  
Hadeer A. Abbassy ◽  
Laila M. Montaser ◽  
Sherin M. Fawzy

<p class="abstract">Musculoskeletal medicine targets both cartilage regeneration and healing of soft tissues. Articular cartilage repair and regeneration is primarily considered to be due to its poor regenerative properties. Cartilage defects due to joint injury, aging, or osteoarthritis have low self-repair ability thus they are most often irreversible as well as being a major cause of joint pain and chronic disability. Unfortunately, current methods do not seamlessly restore hyaline cartilage and may lead to the formation of fibro- or continue hypertrophic cartilage. Deficiency of efficient modalities of therapy has invited research to combine stem cells, scaffold materials and environmental factors through tissue engineering. Articular cartilage tissue engineering aims to repair, regenerate, and hence improve the function of injured or diseased cartilage. This holds great potential and has evoked intense interest in improving cartilage therapy. Platelet-rich plasma (PRP) and/or stem cells may be influential for tissue repair as well as cartilage regenerative processes.  A great promise to advance current cartilage therapies toward achieving a consistently successful modality has been held for addressing cartilage afflictions. The use of stem cells, novel biologically inspired scaffolds and, emerging nanotechnology may be the best way to reach this objective via tissue engineering. A current and emergent approach in the field of cartilage tissue engineering is explained in this review for specific application. In the future, the development of new strategies using stem cells seeded in scaffolds and the culture medium supplemented with growth factors could improve the quality of the newly formed cartilage<span lang="EN-IN">.</span></p>


2020 ◽  
Vol 47 (5) ◽  
pp. 392-403 ◽  
Author(s):  
Min-Sook Kim ◽  
Hyung-Kyu Kim ◽  
Deok-Woo Kim

Severe cartilage defects and congenital anomalies affect millions of people and involve considerable medical expenses. Tissue engineering offers many advantages over conventional treatments, as therapy can be tailored to specific defects using abundant bioengineered resources. This article introduces the basic concepts of cartilage tissue engineering and reviews recent progress in the field, with a focus on craniofacial reconstruction and facial aesthetics. The basic concepts of tissue engineering consist of cells, scaffolds, and stimuli. Generally, the cartilage tissue engineering process includes the following steps: harvesting autologous chondrogenic cells, cell expansion, redifferentiation, <i>in vitro</i> incubation with a scaffold, and transfer to patients. Despite the promising prospects of cartilage tissue engineering, problems and challenges still exist due to certain limitations. The limited proliferation of chondrocytes and their tendency to dedifferentiate necessitate further developments in stem cell technology and chondrocyte molecular biology. Progress should be made in designing fully biocompatible scaffolds with a minimal immune response to regenerate tissue effectively.


Author(s):  
Kalindu Perera ◽  
Ryan Ivone ◽  
Evelina Natekin ◽  
Cheryl. A. Wilga ◽  
Jie Shen ◽  
...  

Cartilage defects pose a significant clinical challenge as they can lead to joint pain, swelling and stiffness, which reduces mobility and function thereby significantly affecting the quality of life of patients. More than 250,000 cartilage repair surgeries are performed in the United States every year. The current gold standard is the treatment of focal cartilage defects and bone damage with nonflexible metal or plastic prosthetics. However, these prosthetics are often made from hard and stiff materials that limits mobility and flexibility, and results in leaching of metal particles into the body, degeneration of adjacent soft bone tissues and possible failure of the implant with time. As a result, the patients may require revision surgeries to replace the worn implants or adjacent vertebrae. More recently, autograft – and allograft-based repair strategies have been studied, however these too are limited by donor site morbidity and the limited availability of tissues for surgery. There has been increasing interest in the past two decades in the area of cartilage tissue engineering where methods like 3D bioprinting may be implemented to generate functional constructs using a combination of cells, growth factors (GF) and biocompatible materials. 3D bioprinting allows for the modulation of mechanical properties of the developed constructs to maintain the required flexibility following implantation while also providing the stiffness needed to support body weight. In this review, we will provide a comprehensive overview of current advances in 3D bioprinting for cartilage tissue engineering for knee menisci and intervertebral disc repair. We will also discuss promising medical-grade materials and techniques that can be used for printing, and the future outlook of this emerging field.


Sign in / Sign up

Export Citation Format

Share Document