The Studies towards Prevention of Osteoarthritis of the knee joint Using Adenovirus Vector Encording Hyaluronic Acid Synthe tase Type-2 Gene

1、由长寿医学科学中心提供透明质酸合成酶2型基因腺病毒载体（HAS2病毒），通过直接注射关节来了解该病毒是否有预防骨关节炎（OA）的作用。将病毒载体注射于兔膝关节或骨性关节炎模型。注射HAS病毒后6周，观察关节液透明质酸（HA）浓度、关节软骨组织学及宏观表现。结果表明：HA病毒注射组（HA病毒组）关节液中HA浓度与野生型病毒注射组（野生组）和载体注射组（载体组）无统计学差异。三组间肉眼及组织学检查均无明显差异。然后，我们确定了HAS2病毒是否对正常（非oa）兔膝盖的HA合成有加速作用。在兔正常膝关节内注射HAS2病毒。结果表明，HAS2病毒组HA浓度有略高于野生组，但低于载体组的趋势。因此，这些结果表明可能是一种负反馈机制影响了结果，或者病毒浓度过低而无法表达HA合成的加速效应。2、我们将研究策略从体内研究改为体外研究，使用关节软骨细胞。透明质酸在软骨组织中也有重要作用，软骨细胞自身也能合成透明质酸。将HAS2病毒感染胎牛关节软骨分离的软骨细胞，在5个时间点收集条件培养基，直到7天。在感染HAS2病毒的软骨细胞条件培养基中，HA浓度在7 d前的任何时间点均高于未感染的软骨细胞。因此，在体外实验中证实了HAS病毒对关节软骨细胞有加速HA合成的作用。这种加速效应可用于关节软骨的组织工程技术或预防OA进展。少

1, Through the courtesy of the Medical Science Center of longevity, the adenovirus vector encording hyaluronic acid synthetase type-2 gene (HAS2 virus) was presented and used to know whether the virus had the prevention effects or osteoarthritis (OA) by injection directly to the joint. The virus vector was injected in the knee joints or rabbit OA model. Then, hyaluronic acid (HA) concentration in joint fluid, macroscopic findings and histology of articular cartilage were evaluated at 6 weeks after HAS virus injection. The result showed that HA concentration in joint fluid of HA virus injected group (HA virus group) had no statistical difference between wild type virus injected group (wild group) and carrier vehicle injected group (carrier group). Macroscopic and histological examination also showed no apparent difference between three groups. Then, we ascertained whether HAS2 virus had the acceleration effects of HA synthesis for normal (non-OA) rabbit knee. HAS2 virus was injected in … More the rabbit normal knee joints. The results showed that HA concentration of HAS2 virus group had the tendency towards a little bit higher than that of wild group, but lower than that of carrier group. Thus, these results indicated that a kind of negative feedback mechanisms might affect the results or the concentration of the virus was too low to express the acceleration effects of HA synthesis.2, We changed the strategy from in vivo study to in vitro study, in which articular chondrocytes were used. HA has some important roles also in cartilage tissue, and chondrocytes themselves synthesize HA.HAS2 virus was infected to the chondrocytes isolated from fetal cow articular cartilage, and condition medium was collected at 5 time points till 7 days. HA concentration in condition medium of HAS2 virus infected chondrocytes was higher than that of non-infeced chondrocytes at any time points till 7 days. Therefore it was verified that HAS virus had the acceleration effects of HA synthesis for articular chondrocytes in vitro. This acceleration effects can be used for tissue engineering technique of articular cartilage or prevention of OA progression. Less