Response of Articular Cartilage to Hyperosmolar Stress: Report of an Ex Vivo Injury Model.

Background: Physiological 0.9% saline is commonly used as an irrigation fluid in modern arthroscopy. There is a growing body of evidence that a hyperosmolar saline solution has chondroprotective effects, especially if iatrogenic injury occurs.

Cell-Laden 3D Printed GelMA/HAp and THA Hydrogel Bioinks: Development of Osteochondral Tissue-like Bioinks.

Osteochondral (OC) disorders such as osteoarthritis (OA) damage joint cartilage and subchondral bone tissue. To understand the disease, facilitate drug screening, and advance therapeutic development, in vitro models of OC tissue are essential. This study aims to create a bioprinted OC miniature construct that replicates the cartilage and bone compartments.

Sound-based assembly of three-dimensional cellularized and acellularized constructs.

Herein we show an accessible technique based on Faraday waves that assist the rapid assembly of osteoinductive β-Tricalcium phosphate (β-TCP) particles as well as human osteoblast pre-assembled in spheroids. The hydrodynamic forces originating at 'seabed' of the assembly chamber can be used to tightly aggregate inorganic and biological entities at packing densities that resemble those of native tissues. Additionally, following a layer-by-layer assembly procedure, centimeter scaled osteoinductive three-dimensional and cellularized constructs have been fabricated.

New Insights into Cartilage Tissue Engineering: Improvement of Tissue-Scaffold Integration to Enhance Cartilage Regeneration.

Distinctive characteristics of articular cartilage such as avascularity and low chondrocyte conversion rate present numerous challenges for orthopedists. Tissue engineering is a novel approach that ameliorates the regeneration process by exploiting the potential of cells, biodegradable materials, and growth factors. However, problems exist with the use of tissue-engineered construct, the most important of which is scaffold-cartilage integration.

Inhibition of hypertrophy and improving chondrocyte differentiation by MMP-13 inhibitor small molecule encapsulated in alginate-chondroitin sulfate-platelet lysate hydrogel.

Background: Mesenchymal stem cells are a promising cell source for chondrogenic differentiation and have been widely used in several preclinical and clinical studies. However, they are prone to an unwanted differentiation process towards hypertrophy that limits their therapeutic efficacy. Matrix metallopeptidase 13 (MMP-13) is a well-known factor regulated during this undesirable event.

Critical-sized bone defects regeneration using a bone-inspired 3D bilayer collagen membrane in combination with leukocyte and platelet-rich fibrin membrane (L-PRF): An in vivo study.

Objectives: We aim to develop a 3D-bilayer collagen (COL) membrane reinforced with nano beta-tricalcium-phosphate (nβ-TCP) particles and to evaluate its bone regeneration in combination with leukocyte-platelet-rich fibrin (L-PRF) in vivo.

Background Data: L-PRF has exhibited promising results as a cell carrier in bone regeneration in a number of clinical studies, however there are some studies that did not confirm the positive results of L-PRF application.

Methods: Mechanical & physiochemical characteristics of the COL/nβ-TCP membrane (1/2 & 1/4) were tested.

3D-porous β-tricalcium phosphate-alginate-gelatin scaffold with DMOG delivery promotes angiogenesis and bone formation in rat calvarial defects.

Hypoxia-inducible factor-1α (HIF-1α), a well-studied angiogenesis pathway, plays an essential role in angiogenesis-osteogenesis coupling. Targeting the HIF-1a pathway frequently leads to successful reconstruction of large-sized bone defects through promotion of angiogenesis. Dimethyloxalylglycine (DMOG) small molecule regulates the stability of HIF-1α at normal oxygen tension by mimicking hypoxia, which subsequently accelerates angiogenesis.

The Robust Potential of Mesenchymal Stem Cell-Loaded Constructs for Hard Tissue Regeneration After Cancer Removal.

Malignant bone tumors, although quite rare, are one of the causes of death in children and adolescents. Surgery as a common and primary treatment for removal of virtually bone cancer cause large bone defects. Thus, restoration of hard tissues like bone and cartilage after surgical tumor resection needs efficient therapeutic approaches.

Development of PLGA-coated β-TCP scaffolds containing VEGF for bone tissue engineering.

Bone tissue engineering is sought to apply strategies for bone defects healing without limitations and short-comings of using either bone autografts or allografts and xenografts. The aim of this study was to fabricate a thin layer poly(lactic-co-glycolic) acid (PLGA) coated beta-tricalcium phosphate (β-TCP) scaffold with sustained release of vascular endothelial growth factor (VEGF). PLGA coating increased compressive strength of the β-TCP scaffolds significantly.

Bone engineering in dog mandible: Coculturing mesenchymal stem cells with endothelial progenitor cells in a composite scaffold containing vascular endothelial growth factor.

We sought to assess the effects of coculturing mesenchymal stem cells (MSCs) and endothelial progenitor cells (EPCs) in the repair of dog mandible bone defects. The cells were delivered in β-tricalcium phosphate scaffolds coated with poly lactic co-glycolic acid microspheres that gradually release vascular endothelial growth factor (VEGF). The complete scaffold and five partial scaffolds were implanted in bilateral mandibular body defects in eight beagles.

Autologous dental pulp stem cells in regeneration of defect created in canine periodontal tissue.

This study aimed to investigate effects of dental pulp stem cells (DPSCs) on regeneration of a defect experimentally created in the periodontium of a canine model. Surgically created mesial 3-walled periodontal defects with ligature-induced periodontitis were produced bilaterally in the first lower premolar teeth of 10 mongrel dogs. Simultaneously, DPSCs were derived from the maxillary premolar teeth of the same dogs.

Amniotic fluid stem cells and their application in cell-based tissue regeneration.

Advances in stem cell biotechnology hold great promise in the field of tissue engineering and regenerative medicine. Of interest are marrow mesenchymal stem cells (MSCs), embryonic stem cells (ESCs), and induced pluripotent stem cells (iPSCs). In addition, amniotic fluid stem cells (AFSCs) have attracted attention as a viable choice following the search for an alternative stem cell source.

Intra-articular injection of autologous mesenchymal stem cells in six patients with knee osteoarthritis.

Background: Osteoarthritis (OA) is a progressive disorder of the joints caused by gradual loss of articular cartilage, which naturally possesses a limited regenerative capacity. In the present study, the potential of intra-articular injection of mesenchymal stem cells (MSCs) has been evaluated in six osteoarthritic patients.

Methods: Six female volunteers, average age of 54.

Mesenchymal stem cells from murine amniotic fluid as a model for preclinical investigation.

Background: Despite the suitability of a mouse model for preclinical investigations; little is known regarding mesenchymal stem cells derived from murine amniotic fluid. This is the subject of the present study. 

Methods:   Amniotic fluid was collected from NMRI mice during the second weeks of pregnancy and plated.