Frenkel S R, Bradica G, Brekke J H, Goldman S M, Ieska K, Issack P, Bong M R, Tian H, Gokhale J, Coutts R D, Kronengold R T
Musculoskeletal Research Center, Department of Orthopedic Surgery, New York University-Hospital for Joint Diseases, New York, NY 10003, USA.
Osteoarthritis Cartilage. 2005 Sep;13(9):798-807. doi: 10.1016/j.joca.2005.04.018.
To investigate whether two different multiphasic implants could initiate and sustain repair of osteochondral defects in rabbits. The implants address the malleable properties of cartilage while also addressing the rigid characteristics of subchondral bone.
The bone region of both devices consisted of D, D-L, L-polylactic acid invested with hyaluronan (HY). The cartilage region of the first device was a polyelectrolytic complex (PEC) hydrogel of HY and chitosan. In the second device the cartilage region consisted of type I collagen scaffold. Eighteen rabbits were implanted bilaterally with a device, or underwent defect creation with no implant. At 24 weeks, regenerated tissues were evaluated grossly, histologically and via immunostaining for type II collagen.
PEC devices induced a significantly better repair than untreated shams. Collagen devices resulted in a quality of repair close to that of the PEC group, although its mean repair score (19.0+/-4.2) did not differ significantly from that of the PEC group (20.4+/-3.7) or the shams (16.5+/-6.3). The percentage of hyaline-appearing cartilage in the repair was highest with collagen implants, while the degree of bonding of repair to the host, structural integrity of the neocartilage, and reconstitution of the subchondral bone was greatest with PEC devices. Cartilage in both device-treated sites stained positive for type II collagen and GAG.
Both implants are capable of maintaining hyaline-appearing tissue at 24 weeks. The physicochemical region between the cartilage and bone compartments makes these devices well suited for delivery of different growth factors or drugs in each compartment, or different doses of the same factor. It also renders these devices excellent vehicles for chondrocyte or stem cell transplantation.
研究两种不同的多相植入物能否启动并维持兔骨软骨缺损的修复。这些植入物既能解决软骨的可塑特性，又能应对软骨下骨的坚硬特性。
两种装置的骨区域均由包埋透明质酸（HY）的D、D-L、L-聚乳酸组成。第一种装置的软骨区域是HY与壳聚糖的聚电解质复合物（PEC）水凝胶。第二种装置的软骨区域由I型胶原支架组成。18只兔双侧植入一种装置，或只制造缺损不植入。24周时，对再生组织进行大体观察、组织学评估及II型胶原免疫染色。
PEC装置诱导的修复明显优于未治疗的假手术组。胶原装置的修复质量接近PEC组，尽管其平均修复评分（19.0±4.2）与PEC组（20.4±3.7）或假手术组（16.5±6.3）相比无显著差异。修复中出现透明样软骨的百分比在胶原植入物中最高，而修复与宿主的结合程度、新软骨的结构完整性以及软骨下骨的重建在PEC装置中最为显著。两种装置处理部位的软骨II型胶原和糖胺聚糖染色均呈阳性。
两种植入物在24周时均能维持透明样组织。软骨和骨区室之间的物理化学区域使这些装置非常适合在每个区室递送不同的生长因子或药物，或相同因子的不同剂量。这也使这些装置成为软骨细胞或干细胞移植的理想载体。
