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An apparatus was developed to apply user-specified displacements to biomaterial samples in culture. The device allowed cyclic waveforms of bandwidth 0 Hz to 20 Hz to be applied under physiologic thermal (37.5°C) and [CO 2] (5%) conditions. For a 0 Hz to 20 Hz bandwidth signal similar in shape to a ventricular pressure waveform, the mean displacement error was 0.26% of the full-scale output. The maximum overshoot was 0.700%. Environmental system evaluation tests demonstrated a specimen cartridge temperature of 37.20±0.15°C during cyclic loading and 37.23±0.21°C during static conditions, [CO 2] was 5.29±0.54% during cyclic loading and 5.25±0.61% during static conditions. Laminar flow applied at the loading rod entrances to the specimen cartridge ensured the sample remained sterile during testing. As a preliminary evaluation, polyurethane samples were seeded with fetal foreskin fibroblasts and subject to intermittent cyclic displacements. Results demonstrated enhanced cell proliferation and increased [PGE 2] for samples subjected to 10% strain compared with unstrained controls. A next step will be to evaluate cell response sensitivity to strain magnitude, duration, direction, and frequency. The long-term intent is to establish mechanical loading configurations that induce acceptable or adaptation-inducing responses for use in implant design and tissue engineering applications.