The effects of varying frequency and duration of mechanical stimulation on a tissue-engineered tendon construct.

Decellularized, discarded human tissues, such as the human umbilical vein, have been widely utilized for tissue engineering applications, including tendon grafts. When recellularized, such natural scaffolds are cultured in 3D dynamic culture environments (bioreactor systems). For tendon tissue-engineered grafts, such systems often employ oscillatory mechanical stimulation in the form uniaxial tensile strain.

Tenocytic extract and mechanical stimulation in a tissue-engineered tendon construct increases cellular proliferation and ECM deposition.

Chemical and mechanical stimulation, when properly utilized, positively influence both the differentiation of in vitro cultured stem cells and the quality of the deposited extracellular matrix (ECM). This study aimed to find if cell-free extract from primary tenocytes can positively affect the development of a tissue-engineered tendon construct, consisting of a human umbilical vein (HUV) seeded with mesenchymal stem cells (MSCs) subjected to cyclical mechanical stimulation. The tenocytic cell-free extract possesses biological material from tendon cells that could potentially influence MSC tenocytic differentiation and construct development.

Long-term in vivo effect of PEG bone tissue engineering scaffolds.

Polyethylene glycol (PEG) performs multiple roles for bone tissue engineering scaffolds. Successful in vivo implantation for long periods of time requires a scaffold that is biocompatible, osteoconductive, osteoinductive, and promotes cell recruitment and attachment. PEG has significant advantages such as excellent biocompatibility and flexibility, but certain drawbacks such as poor mechanical strength and cell attachment limit its use as a plain scaffold.

The effect of cell seeding density on the cellular and mechanical properties of a mechanostimulated tissue-engineered tendon.

The initial seeding density is a critical variable in functional tissue engineering. A sufficient number of cells uniformly distributed throughout the scaffold is a key requirement to achieve homogeneous extracellular matrix deposition in vitro. However, high initial seeding densities might have negative repercussions on nutrient availability, cellular metabolism, and cell viability.