Disorganized collagen scaffold interferes with fibroblast mediated deposition of organized extracellular matrix in vitro.

Many tissue engineering applications require the remodeling of a degradable scaffold either in vitro or in situ. Although inefficient remodeling or failure to fully remodel the temporary matrix can result in a poor clinical outcome, very few investigations have examined in detail, the interaction of regenerative cells with temporary scaffoldings. In a recent series of investigations, randomly oriented collagen gels were directly implanted into human corneal pockets and followed for 24 months.

Design and performance of an optically accessible, low-volume, mechanobioreactor for long-term study of living constructs.

Currently available bioreactor systems used by tissue engineers permit either direct, high-magnification observation of cell behavior or application of mechanical loads to growing tissue constructs, but not both simultaneously. Further, in most loading bioreactors, the volume of the dead space is not minimized to reduce the cost associated with perfusion media, exogenous stimulatory/inhibitory agents, proteases, and label. We have designed, developed, and tested a bioreactor that simultaneously satisfies the combined requirements of providing (i) controlled tensile mechanical stimulation, (ii) direct high-magnification imaging capability, and (iii) low dead-space volume.

Morphologic characterization of organized extracellular matrix deposition by ascorbic acid-stimulated human corneal fibroblasts.

Purpose: To characterize the structure and morphology of extracellular matrix (ECM) synthesized by untransformed, cultured human corneal fibroblasts in long-term cultures.

Methods: Human corneal stromal keratocytes were expanded in transwell culture in the presence of fetal bovine serum and a stable derivative of vitamin C. The cells were allowed to synthesize a fibrillar ECM for up to 5 weeks.