Cartilage mechanobiology

The cartilage is a highly pressurized tissue, in which chondrocytes metabolically secrete highly charged proteoglycans that create swelling pressure in a dense and rigid collagen scaffold. The pressurization is further exacerbated by load-bearing duties which pressurize the interstitial fluids of the cartilage. As a postdoc in the Chaudhuri lab at Stanford, I am investigating how this pressurized environment influences cellular function in chondrocytes [1]. To do this, I am studying chondrocyte behavior in 3-D in vitro models of the articular cartilage, consisting of chondrocytes embedded in engineered hydrogels of tunable viscoelasticity, which differentially gate metabolically-secreted proteins to create different pressurized environments for the chondrocytes. I am also studying how these cellular responses are amplified by external mechanical loads. These studies elucidate new mechanisms through which cells sense the mechanical properties of their microenvironment, and highlight fundamental processes underlying the development and maturation of tissues such as the cartilage.

Schematic illustration of the confinement pressure generated by the cellular secretion of extracellular proteins in a highly dense and elastic collagen scaffold of the articular cartilage.

1. Song, J., Jones, S., Yang, F., Bhutani, N., Levenston, M. E., & Chaudhuri, O. “Cell-Secreted Extracellular Matrix Mediates Chondrocyte Mechanosensation of Microenvironment Viscoelasticity.” Manuscript in preparation.