Center of Experimental Orthopaedics, Saarland University Medical Center , Homburg, Germany.
Departamento de Farmacia y Tecnología Farmacéutica, R+DPharma Group (GI-1645), Facultad de Farmacia, Universidade de Santiago de Compostela , Santiago de Compostela, Spain.
ACS Appl Mater Interfaces. 2016 Aug 17;8(32):20600-13. doi: 10.1021/acsami.6b06509. Epub 2016 Aug 3.
Gene therapy is an attractive strategy for the durable treatment of human osteoarthritis (OA), a gradual, irreversible joint disease. Gene carriers based on the small human adeno-associated virus (AAV) exhibit major efficacy in modifying damaged human articular cartilage in situ over extended periods of time. Yet, clinical application of recombinant AAV (rAAV) vectors remains complicated by the presence of neutralizing antibodies against viral capsid elements in a majority of patients. The goal of this study was to evaluate the feasibility of delivering rAAV vectors to human OA chondrocytes in vitro and in an experimental model of osteochondral defect via polymeric micelles to protect gene transfer from experimental neutralization. Interaction of rAAV with micelles of linear (poloxamer PF68) or X-shaped (poloxamine T908) poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO) copolymers (PEO-PPO-PEO micelles) was characterized by means of isothermal titration calorimetry. Micelle encapsulation allowed an increase in both the stability and bioactivity of rAAV vectors and promoted higher levels of safe transgene (lacZ) expression both in vitro and in experimental osteochondral defects compared with that of free vector treatment without detrimental effects on the biological activity of the cells or their phenotype. Remarkably, protection against antibody neutralization was also afforded when delivering rAAV via PEO-PPO-PEO micelles in all systems evaluated, especially when using T908. Altogether, these findings show the potential of PEO-PPO-PEO micelles as effective tools to improve current gene-based treatments for human OA.
基因治疗是一种有吸引力的策略，可以持久治疗人类骨关节炎（OA），这是一种逐渐的、不可逆转的关节疾病。基于小型人腺相关病毒（AAV）的基因载体在长时间内原位修饰受损的人关节软骨方面表现出显著的疗效。然而，重组 AAV（rAAV）载体的临床应用仍然受到大多数患者存在针对病毒衣壳元件的中和抗体的影响。本研究的目的是评估通过聚合物胶束将 rAAV 载体递送至体外和实验性骨软骨缺损模型中的人类 OA 软骨细胞的可行性，以防止基因转移受到实验性中和作用的影响。通过等温滴定微量热法来表征 rAAV 与线性（泊洛沙姆 PF68）或 X 形（聚氧乙烯 T908）聚（氧化乙烯）（PEO）和聚（氧化丙烯）（PPO）嵌段共聚物（PEO-PPO-PEO 胶束）的相互作用。胶束包封允许 rAAV 载体的稳定性和生物活性均增加，并促进了更高水平的安全转基因（lacZ）表达，无论是在体外还是在实验性骨软骨缺损中，与游离载体处理相比，对细胞的生物学活性或表型没有不利影响。值得注意的是，当通过 PEO-PPO-PEO 胶束递送 rAAV 时，在所有评估的系统中都提供了针对抗体中和的保护作用，尤其是在使用 T908 时。总的来说，这些发现表明 PEO-PPO-PEO 胶束作为有效工具，具有改善当前针对人类 OA 的基因治疗的潜力。
