Studies on the stem cell niche and the efficacy of cancer therapeutics require complex multicellular structures and interactions between different cell types and extracellular matrix (ECM) in three dimensional (3D) space. We have engineered a 3D in vitro model of mammary gland that encompasses a defined, porous collagen/hyaluronic acid (HA) scaffold forming a physiologically relevant foundation...

Electrospun nanofibers have been used for various biomedical applications. However, electrospinning commonly produces two-dimensional (2D) membranes, which limits the application of nanofibers for the 3D tissue engineering scaffold. In the present study, a porous 3D scaffold (3DS-1) based on electrospun gelatin/PLA nanofibers has been prepared for cartilage tissue regeneration. To further impro...

Collagen and hyaluronic acid (HA) are main components of the extracellular matrix and have been utilized in electrospinning; a technique that creates nanosized fibers for tissue scaffolds. A collagen/HA polymer solution was electrospun into a scaffold material for osteoporosis patients who have reduced bone strength. To synthesize nanofibers, a high voltage was applied to the polymer solution t...

Bio-engineered skin and soft tissue substitutes may be either acellular or cellular. Acellular products (i.e., cadaveric human dermis with cellular material removed) contain a matrix or scaffold composed of materials such as collagen, hyaluronic acid, and fibronectin. Cellular products contain living cells such as fibroblasts and keratinocytes within a matrix. The cells contained within the mat...

Recent investigations into micro-architecture of scaffolds has revealed that mean pore sizes are cell-type specific and influence cellular shape, differentiation, and extracellular matrix secretion. In this context, the overall goal of this study was to investigate whether scaffold mean pore sizes affect mesenchymal stem cell initial attachment, chondrogenic gene expression, and cartilage-like ...

Synthesis of hyaluronic acid was investigated in a cell-free system derived from a strain of Group A streptococci. Preparative procedures were improved so that an enzyme system 70 times more active than that previously reported was obtained. The hyaluronic acid synthesized could be separated into trichloroacetic acid-soluble and -insoluble fractions. On the basis of pulse-chase experiments, it ...

When the concentration of hyaluronic acid was monitored in primary cultures of mouse skin dermal fibroblasts, there was an increase in hyaluronic acid proportional to the increase in cell number during the logarithmic growth phase. The concentration reached the maximum value 2 days before the cells became confluent, and then decreased gradually. Hyaluronic acid added at 1 mg ml-1 during the log...