Tissue Engineering of Cartilage Subtypes

描述（由申请人提供）： 人们普遍认为，细胞通过改变它们的基因表达来响应可溶性因子和生物力学力。来自不同解剖位置的软骨细胞都表达一组共同的基质分子，但这些基质分子要么以不同的水平表达，要么在不同解剖位置的软骨中以不同的方式组装。据推测，生物力学力与局部可溶性因子的组合是负责细胞外基质的差异组装。进一步假设，通过将软骨细胞从一个解剖位置移动到另一个解剖位置，软骨细胞将采用植入部位的基质结构。拟议研究的目的是使用从耳、鼻、关节和气管软骨中分离的软骨细胞来检验这一假设，这些软骨细胞已在培养中扩增并与有利于软骨产生的基质结合。这些不同解剖结构的结构将被转换到不同的解剖部位，沿着将对照结构植入回其原始部位。随着时间的推移，将收获样本并进行生物力学、生物化学和免疫组织化学分析，以确定植入的软骨细胞是否已调节其细胞外基质以匹配植入部位。在进行植入物实验之前，将收集关于天然软骨的生物化学、生物力学和免疫组织化学特征的基线数据。最后，将在兔喉气管重建的临床前模型中测试软骨细胞。这项研究解决了复杂的基质组装如何调节的基本问题，并测试了易于获得的耳廓软骨细胞在喉气管重建的临床前模型中的实际应用，该模型将测试移植的工程软骨是否具有足够的生物力学强度和长期稳定性以开发用于人类。

DESCRIPTION (provided by applicant): It is well accepted that cells respond both to soluble factors and to biomechanical forces by altering their gene expression. Chondrocytes from different anatomic locations all express a set of common matrix molecules, but those matrix molecules are either expressed at different levels or are assembled differently in cartilage at different anatomic locations. It is postulated that biomechanical forces in combination with local soluble factors are responsible for the differential assembly of the extracellular matrix. It is further hypothesized that by moving chondrocytes from one anatomic location to another, the chondrocytes will adopt the matrix structure of the implantation site. The objective of the proposed studies is to test this hypothesis using chondrocytes isolated from auricular, nasal, articular, and tracheal cartilage that have been expanded in culture and combined with a matrix that is conducive to cartilage production. These constructs of different anatomic origin will be switched into different anatomic sites, along with control constructs implanted back to their site of origin. Over time, the samples will be harvested and will undergo biomechanical, biochemical and immunohistochemical analyses to determine if the implanted chondrocytes have modulated their extracellular matrix to match the implant site. Prior to conducting the implant experiments, baseline data on the biochemical, biomechanical and immunohistochemical characteristics of native cartilage will be complied. Finally, chondrocytes will be tested in a pre-clinical model of laryngeal tracheal reconstruction in rabbits. This study addresses both the fundamental question of how complex matrix assembly is regulated and tests the practical use of easily-obtained auricular chondrocytes in a preclinical model for laryngeal-tracheal reconstruction that will test whether transplanted engineered cartilage has sufficient biomechanical strength and long-term stability to be developed for use in humans.