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Updated: May 23, 2026
Mechanical Stimulation of Chondrocyte-agarose Hydrogels
Published on: October 27, 2012
Continuous cyclic compressive loading modulates biological and mechanical properties of collagen hydrogels seeded
Sven Nebelung1, Karsten Gavenis, Björn Rath
1Department of Orthopaedics and Trauma Surgery, Aachen University Hospital, Aachen, Germany. Sven.Nebelung@rwth-aachen.de
Purpose:
This study investigated the potential of cyclic compressive loading in the generation of in vitro engineered cartilaginous tissue with the aim of contributing to a better understanding of mechanical preconditioning and its possible role in further optimizing existing matrix-associated cartilage replacement procedures.
Methods:
Human chondrocytes were harvested from 12 osteoarthritic knee joints and seeded into a type I collagen (col-I) hydrogel at low density (2 × 10(5) cells/ml gel). The cell-seeded hydrogel was condensed and cultivated under continuous cyclic compressive loading (frequency: 0.3 Hz; strain: 10%) for 14 days under standardized conditions. After retrieval, specimens were subject to staining, histomorphometric evaluation, gene expression analysis and biomechanical testing.
Results:
Cellular morphology was altered by both stimulation and control conditions as was staining for collagen II (col-II). Gene expression measurements revealed a significant increase for col-II under either cultivation condition. No significant differences in col-I, aggrecan and MMP-13 gene expression profiles were found. The col-II/col-I mRNA ratio significantly increased under stimulation, whereas the biomechanical properties deteriorated under either cultivation method.
Conclusions:
Although the effects observed are small, mechanical preconditioning has demonstrated its potential to modulate biological properties of collagen hydrogels seeded with human chondrocytes.
