中文摘要：

目的：观察B7-H4在大鼠创伤性关节炎模型中的表达及变化情况,探讨其在创伤性关节炎中的作用及可能的机制。方法：将52只健康雄性SD大鼠随机分为实验组和对照组,每组26只。实验组行右后膝关节内侧副韧带和内侧半月板切除术;对照组行单侧膝关节切开术作为假手术对照。两组分别在术后24 h、48 h、1周、2周、4周5个时间点抽取关节液,采用酶联免疫吸附法（ELISA）测定关节液中B7-H4含量表达。结果：对照组术后各时间点B7-H4含量表达均较低,各时间点B7-H4含量差异无统计学意义（P〉0.05）;实验组术后各时间点B7-H4含量均高于对照组（均P〈0.05）;实验组术后48 h膝关节液中B7-H4含量较其他时间点明显增高（P〈0.05）;术后2周B7-H4表达较术后48 h明显降低（P〈0.05）;术后48 h、2周、4周3个时间点的B7-H4表达呈降低趋势。结论：B7-H4在创伤急性期的关节中表达增高,其在创伤愈合后期表达逐渐降低,同时对自身免疫反应抑制减弱与创伤性关节炎的发生、发展密切相关。

英文摘要：

Objective：The expressions and changes of B7-H4 in the post-traumatic osteoarthritis model in rats were observed in order to further elucidate the effect and possible mechanism in post-traumatic osteoarthritis.Methods：52 male SD rats were divided into experimental group and control group randomly with 26 in each group.The medial collateral ligament,and full medial meniscus of the right-posterior knee were cut off for the experimental group,while the control group was subjected to unilateral arthrotomy as pseudo operative controls.The specimens were collected at various time points after the surgery（24 h,48 h and 1,2,4 week respectively）.the enzyme-linked immunosorbent assay（ELISA） was performed to measure the expression of B7-H4.Results：The expression of B7-H4 in control group was very low,the differences between different time points have no statistical significance（P0.05）;The expression of B7-H4 in experimental group at all time points was significantly higher than those in control group（P0.05）;The expression of B7-H4 in experimental group at 48 h was significantly higher than those at any other time points（P0.05）;Compared with the expression of B7-H4 at 48 h,that at 2 week decreased remarkably（P0.05）;The expression of B7-H4 descended in proper order of 48 h,2 and 4 week.Conclusion：At the acute stage of post-traumatic osteoarthritis,the expression of B7-H4 is upgraded,and the degradation appearance at the post-healing stage.The weakened inhibition to autoimmune response is intimately correlated with traumatic arthritis.