Title:

Bioengineering of Articular Cartilage and Synovial Fluid: Foundations for Biological Joint Replacement

Speaker:

Dr. Robert L. Sah

Affiliation:

University of California, San Diego

When:

Tuesday, August 17, 2010 at 11:00:00 AM   Add to Calendar

Where:

IBB Building, Room 1128

Host:

Johnna Temenoff
johnna.temenoff@bme.gatech.edu

Abstract

Joint articulation involves the relative motion of apposing cartilage surfaces, sliding past each other in a synovial fluid solution. The tribological and load-bearing properties of cartilage that facilitate biomechanical behavior serve as design targets for engineered tissues. The load-bearing properties of cartilage vary markedly from the articular surface to the subchondral bone, due the depth-varying aggrecan content as well as the dense, resilient collagen network.

The low-friction and low-wear properties of cartilage are due in part to lubricating molecules in synovial fluid, particularly proteoglycan 4 and hyaluronan. The shear to which the articular cartilage and indwelling chondrocytes are subjected is governed both by the friction-dependent shear stress within, and the shear modulus of, cartilage near the articular surface. The lubricating properties of synovial fluid for articular surface can be diminished in injury and disease due to changes in the concentration of hyaluronan or proteoglycan 4. Such alterations may disrupt the mechanobiology of the synovial joint.

The bioengineering of articular cartilage and synovial fluid materials may be useful both for scientific and therapeutic purposes. Biotechnologies targeting cell expansion and assembly as well as bioreactor culture can facilitate both the formation of a porous material like articular cartilage and of a liquid lubricant like synovial fluid. The quest to attain material phenotypes resembling native articular cartilage and synovial fluid in health and disease challenges our understanding of the synovial joint at multiple scales. A sufficient understanding and successful fabrication of osteochondral structures in joint-scale bioreactors may lead to future-generation therapies such as biological joint replacement.

Biography

A biographical statement from Dr. Sah was not included with the announcement.