Dynamics of extracellular matrix production and turnover in tissue engineered cardiovascular structures

作者：Stock UA^*; Wiederschain D; Kilroy SM; Shum Tim D; Khalil PN; Vacanti JP; Mayer JE; Moses MA

来源：Journal of Cellular Biochemistry, 2001, 81(2): 220-228.

DOI：10.1002/1097-4644(20010501)81:2<220::AID-JCB1037>3.0.CO;2-O

• extracellular matrix
• remodeling
• tissue engineering
• blood vessels

Appropriate matrix formation, turnover and remodeling in tissue-engineered small diameter vascular conduits are crucial requirements for their long-term patency and function. This complex process requires the deposition and accumulation of extracellular matrix molecules as well as the remodeling of this extracellular matrix (ECM) by matrix metalloproteinases (MMPs) and their endogenous inhibitors (TIMPs). In this study, we have investigated the dynamics of ECM production and the activity of MMPs and TIMPs in long-term tissue-engineered vascular conduits using quantitative ECM analysis, substrate gel electrophoresis, radiometric enzyme assays and Western blot analyses. Over a time period of 169 days in vivo, levels of elastin and proteoglycans/glycosaminoglycans in tissue-engineered constructs came to approximate those of their native tissue counter parts. The kinetics of collagen deposition and remodeling, however, apparently require a much longer time period. Through the use of substrate gel electrophoresis, proteolytic bands whose molecular weight was consistent with their identification as the active form of MMP-2 (approximate to 64-66 kDa) were detected in ail native and tissue-engineered samples. Additional proteolytic bands migrating at approximate to 72 kDa representing the latent form of MMP-2 were detected in tissue-engineered samples at time points from 5 throughout 55 days. Radiometric assays of MMP-1 activity demonstrated no significant differences between the native and tissue-engineered samples. This study determines the dynamics of ECM production and turnover in a long-term tissue-engineered vascular tissue and highlights the importance of ECM remodeling in the development of successful tissue-engineered vascular structures.

• 出版日期2001