Riesle J, Hollander A P, Langer R, Freed L E, Vunjak-Novakovic G
Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge 02139, USA.
J Cell Biochem. 1998 Dec 1;71(3):313-27. doi: 10.1002/(sici)1097-4644(19981201)71:3<313::aid-jcb1>3.0.co;2-c.
The function of articular cartilage as a weight-bearing tissue depends on the specific arrangement of collagen types II and IX into a three-dimensional organized collagen network that can balance the swelling pressure of the proteoglycan/water gel. To determine whether cartilage engineered in vitro contains a functional collagen network, chondrocyte-polymer constructs were cultured for up to 6 weeks and analyzed with respect to the composition and ultrastructure of collagen by using biochemical and immunochemical methods and scanning electron microscopy. Total collagen content and the concentration of pyridinium crosslinks were significantly (57% and 70%, respectively) lower in tissue-engineered cartilage that in bovine calf articular cartilage. However, the fractions of collagen types II, IX, and X and the collagen network organization, density, and fibril diameter in engineered cartilage were not significantly different from those in natural articular cartilage. The implications of these findings for the field of tissue engineering are that differentiated chondrocytes are capable of forming a complex structure of collagen matrix in vitro, producing a tissue similar to natural articular cartilage on an ultrastructural scale.
关节软骨作为负重组织的功能取决于II型和IX型胶原蛋白在三维有序胶原网络中的特定排列，该网络能够平衡蛋白聚糖/水凝胶的肿胀压力。为了确定体外构建的软骨是否含有功能性胶原网络，将软骨细胞-聚合物构建体培养长达6周，并使用生化和免疫化学方法以及扫描电子显微镜对胶原的组成和超微结构进行分析。与小牛关节软骨相比，组织工程软骨中的总胶原含量和吡啶交联浓度显著降低（分别降低57%和70%）。然而，工程软骨中II型、IX型和X型胶原蛋白的比例以及胶原网络的组织、密度和纤维直径与天然关节软骨中的并无显著差异。这些发现对组织工程领域的意义在于，分化的软骨细胞能够在体外形成复杂的胶原基质结构，在超微结构尺度上产生与天然关节软骨相似的组织。
