To date, static culture for the tissue engineering of articular cartilage has shown to be inadequate
in conferring functionality to constructs. Various forms of mechanical stimuli accompany articular
cartilage development in vivo, and one of these is hydrostatic pressure. This study used histology,
biochemistry, and biomechanics to examine the effects of intermittent hydrostatic pressure, applied
at 10 MPa and 1 Hz for 4 h per day for 5 days per week for up to 8 weeks on self-assembled chondrocyte
constructs. The self-assembling process is a novel approach that allows engineering of articular
cartilage constructs without the use of exogenous scaffolds. The self-assembled constructs
were found to be capable of enduring this loading regimen. Significant increases in collagen production
were only observed in pressurized samples. Intermittent hydrostatic pressure prevented a
significant decrease in total GAG, which was significant in controls. Aside from the beneficial effects
intermittent hydrostatic pressure may have on ECM synthesis, its effects on mechanical properties
may require longer culture periods to manifest. This study demonstrates the successful use of
the self-assembling process to produce articular cartilage constructs. It also shows for the first time
that long-term culture of tissue-engineered articular cartilage construct benefits from intermittent
hydrostatic pressure.
