Hemodynamic evaluation of biomaterial-based surgery for Tetralogy of Fallot using a biorobotic heart, in silico, and ovine models.

Tetralogy of Fallot is a congenital heart disease affecting newborns and involves stenosis of the right ventricular outflow tract (RVOT). Surgical correction often widens the RVOT with a transannular enlargement patch, but this causes issues including pulmonary valve insufficiency and progressive right ventricle failure. A monocusp valve can prevent pulmonary regurgitation; however, valve failure resulting from factors including leaflet design, morphology, and immune response can occur, ultimately resulting in pulmonary insufficiency.

The potential of cell-assembled extracellular matrix for biological sutures: A promising innovation.

Most surgical procedures require using suture materials that are mechanically efficient and accepted by the patient's body. These sutures are essentially composed of synthetic polymers. However, once implanted in patients, they are recognized as foreign bodies and generate chronic inflammation.

Development and characterization of biological sutures made of cell-assembled extracellular matrix.

Most vascular surgical repair procedures, such as vessel anastomoses, requires using suture materials that are mechanically efficient and accepted by the patient's body. These materials are essentially composed of synthetic polymers, such as polypropylene (Prolene) or polyglactin (Vicryl). However, once implanted in patients, they are recognized as foreign bodies, and the patient's immune system will degrade, encapsulate, or even expel them.

Current biofabrication methods for vascular tissue engineering and an introduction to biological textiles.

Cardiovascular diseases are the leading cause of mortality in the world and encompass several important pathologies, including atherosclerosis. In the cases of severe vessel occlusion, surgical intervention using bypass grafts may be required. Synthetic vascular grafts provide poor patency for small-diameter applications (< 6 mm) but are widely used for hemodialysis access and, with success, larger vessel repairs.

Inter-donor variability of extracellular matrix production in long-term cultures of human fibroblasts.

Several tissue engineering approaches are based on the ability of mesenchymal cells to endogenously synthesize an extracellular matrix (ECM) , which can be seen as a form of biomaterial. Accordingly, the inter-donor variability of cell-assembled extracellular matrix (CAM) production is a key parameter to understand in order to progress towards clinical applications, especially for autologous strategies. In this study, CAMs were produced, under good manufacturing process conditions, from skin fibroblasts of 21 patients as part of a clinical trial to evaluate a tissue-engineered vascular graft.

Preclinical Evaluation of BMP-9-Treated Human Bone-like Substitutes for Alveolar Ridge Preservation following Tooth Extraction.

The success of dental implant treatment after tooth extraction is generally maximized by preserving the alveolar ridge using cell-free biomaterials. However, these treatments can be associated with inflammatory reactions, leading to additional bone volume loss hampering dental implant positioning. Our group developed a self-assembled bone-like substitute constituted of osteogenically induced human adipose-derived stromal/stem cells (hASCs).

In Vitro Prevascularization of Self-Assembled Human Bone-Like Tissues and Preclinical Assessment Using a Rat Calvarial Bone Defect Model.

In vitro prevascularization has the potential to address the challenge of maintaining cell viability at the core of engineered constructs, such as bone substitutes, and to improve the survival of tissue grafts by allowing quicker anastomosis to the host microvasculature. The self-assembly approach of tissue engineering allows the production of biomimetic bone-like tissue constructs including extracellular matrix and living human adipose-derived stromal/stem cells (hASCs) induced towards osteogenic differentiation. We hypothesized that the addition of endothelial cells could improve osteogenesis and biomineralization during the production of self-assembled human bone-like tissues using hASCs.

In vivo remodeling of human cell-assembled extracellular matrix yarns.

Cell-assembled extracellular matrix (CAM) has been used to produce vascular grafts. While these completely biological vascular grafts performed well in clinical trials, the in vivo remodeling and inflammatory response of this truly "bio" material has not yet been investigated. In this study, human CAM yarns were implanted subcutaneously in nude rats to investigate the innate immune response to this matrix.

Cell-assembled extracellular matrix (CAM) sheet production: Translation from using human to large animal cells.

We have created entirely biological tissue-engineered vascular grafts (TEVGs) using sheets of cell-assembled extracellular matrix (CAM) produced by human fibroblasts . A large animal TEVG would allow long-term pre-clinical studies in a clinically relevant setting (graft size and allogeneic setting). Therefore, canine, porcine, ovine, and human skin fibroblasts were compared for their ability to form CAM sheets.

Biofabrication and preclinical evaluation of a large-sized human self-assembled skin substitute.

Severe skin burns are widely treated using split-thickness skin autografts. However, the accessibility of the donor site may be limited depending on the size of the injured surface. As an alternative to skin autografts, our laboratory is clinically investigating a model of human self-assembled skin substitute (SASS) with a standard size of 35 cm.

Biomimetic Tissue-Engineered Bone Substitutes for Maxillofacial and Craniofacial Repair: The Potential of Cell Sheet Technologies.

Maxillofacial defects are complex lesions stemming from various etiologies: accidental, congenital, pathological, or surgical. A bone graft may be required when the normal regenerative capacity of the bone is exceeded or insufficient. Surgeons have many options available for bone grafting including the "gold standard" autologous bone graft.

A Cell-Based Self-Assembly Approach for the Production of Human Osseous Tissues from Adipose-Derived Stromal/Stem Cells.

Achieving optimal bone defect repair is a clinical challenge driving intensive research in the field of bone tissue engineering. Many strategies focus on seeding graft materials with progenitor cells prior to in vivo implantation. Given the benefits of closely mimicking tissue structure and function with natural materials, the authors hypothesize that under specific culture conditions, human adipose-derived stem/stromal cells (hASCs) can solely be used to engineer human reconstructed osseous tissues (hROTs) by undergoing osteoblastic differentiation with concomitant extracellular matrix production and mineralization.

Tissue-Engineered Tubular Heart Valves Combining a Novel Precontraction Phase with the Self-Assembly Method.

Recently, the tubular shape has been suggested as an effective geometry for tissue-engineered heart valves, allowing easy fabrication, fast implantation, and a minimal crimped footprint from a transcatheter delivery perspective. This simple design is well suited for the self-assembly method, with which the only support for the cells is the extracellular matrix they produce, allowing the tissue to be completely free from exogenous materials during its entire fabrication process. Tubular constructs were produced by rolling self-assembled human fibroblast sheets on plastic mandrels.