Journal of Stem Cell Research & Therapy

Doublecortin and tissue engineering/regeneration of articular cartilage

International Conference on Regenerative & Functional Medicine

November 12-14, 2012 Hilton San Antonio Airport, USA

Zongbing You

Scientific Tracks Abstracts: J Stem Cell Res Ther

Abstract:

It is estimated that 24.3 million American adults have osteoarthritis. The current clinical treatments, other than total joint replacement, do not change the course of osteoarthritis. Regenerative medicine, including tissue engineering, offers exciting opportunities to restore functional articular cartilage. However, currently the tissue-engineered cartilages behave like physeal (within growth plates) or endochondral (within the cartilaginous anlagen of future bones) cartilages that undergo premature hypertrophy, unlike the stable articular cartilage that lasts a lifetime. Articular cartilage and physeal/endochondral cartilage are both hyaline cartilages. However, we have found 107 genes that are highly (≥ 5 fold) expressed in the surface articular chondrocytes, while 129 genes are highly expressed in the resting zone chondrocytes of growth plate. Doublecortin (DCX) is one of the genes highly expressed in immature articular chondrocytes but not expressed in growth plates. DCX is expressed in the mesenchymal stem/precursor cells of the osteo-chondral lineage in the mouse embryonic limbs at embryonic days of 9.5 to 12.5. DCX expression is maintained when the stem/precursor cells differentiate into articular chondrocytes at embryonic day 13.5 up to a few weeks after birth. In contrast, DCX expression is turned off when the stem/precursor cells differentiate into endochondral chondrocytes. Indeed, when DCX expression is maintained in human adipose tissue-derived mesenchymal stem cells during their differentiation into chondrocytes, the resulting chondrocytes express higher levels of genes that are specifically expressed in articular chondrocytes. Therefore, it is potentially possible to manipulate DCX expression during tissue engineering or regeneration of bona fide articular cartilage.

Biography :

Dr. You obtained his MD in 1989 and PhD in 1994 from the West China University of Medical Sciences. He has performed postdoctoral studies at the Beijing Medical University in China, Freiburg University in Germany, and University of Michigan in the USA. He is an Assistant Professor in the Department of Structural & Cellular Biology and the Department of Orthopaedic Surgery, Member of the Tulane Cancer Center, Louisiana Cancer Research Consortium, Tulane Center for Aging, and Tulane Center for Stem Cell Research and Regenerative Medicine at Tulane University School of Medicine. Dr. You has published 45 papers in scientific journals.