Tanaka Takaaki, Komaki Hirokazu, Chazono Masaaki, Fujii Katsuyuki
Department of Orthopedic Surgery, NHO Utsunomiya National Hospital, Tochigi, Japan.
Tissue Eng. 2005 Jan-Feb;11(1-2):331-9. doi: 10.1089/ten.2005.11.331.
To evaluate the ability of a biphasic construct to repair osteochondral defects in articular cartilage, plugs made of chondrocytes in collagen gel overlying a resorbable porous beta-tricalcium phosphate (TCP) block were implanted into defects in rabbit knees. The repair tissue was evaluated at 8, 12, and 30 weeks. Eight weeks after implantation of the biphasic construct, histologic examination showed hyaline-like cartilage formation that was positive for safranin O and type II collagen. At 12 weeks, most of the beta-TCP was replaced by bone, with a small amount remaining in the underlying cartilage. In the cell-seeded layer, the newly formed middle and deep cartilage adjacent to the subchondral bone stained with safranin O, but no staining was observed in the superficial layer. In addition, cell morphology was distinctly different from the deep levels of the reparative cartilage, with hypertrophic cells at the bottom of the cartilaginous layer. At 30 weeks, beta-TCP had completely resorbed and a tidemark was observed in some areas. In contrast, controls (defects filled with a beta-TCP block alone) showed no cartilage formation but instead had subchondral bone formation. These findings indicate that beta-TCP-supported chondrocytes in collagen gel can partially repair isolated articular cartilage osteochondral defects.
为评估双相结构修复关节软骨骨软骨缺损的能力，将由胶原凝胶中的软骨细胞制成的塞子覆盖在可吸收多孔β-磷酸三钙（TCP）块上，植入兔膝关节的缺损处。在8周、12周和30周时对修复组织进行评估。双相结构植入8周后，组织学检查显示形成了番红O和II型胶原阳性的透明样软骨。12周时，大部分β-TCP被骨替代，少量残留在下方软骨中。在细胞种植层，与软骨下骨相邻的新形成的中层和深层软骨用番红O染色，但表层未观察到染色。此外，细胞形态与修复软骨的深层明显不同，软骨层底部有肥大细胞。30周时，β-TCP已完全吸收，部分区域观察到潮标。相比之下，对照组（仅用β-TCP块填充缺损）未形成软骨，而是形成了软骨下骨。这些发现表明，胶原凝胶中β-TCP支持的软骨细胞可部分修复孤立的关节软骨骨软骨缺损。
