髋臼发育不良股骨头软骨退行性变时序性和可逆性的实验研究
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摘要
[背景和目的]
发育性髋关节发育不良(Developmental dysplasia of the hip, DDH)是小儿常见的四肢畸形之一。随着早期筛查的开展,很多DDH患儿能够得到闭合复位等早期治疗,但其中相当一部分会出现残余髋臼发育不良,以后进展为骨关节炎(Osteoarthritis, OA)。目前对于残余髋臼发育不良治疗时机的选择有不同观点,残余髋臼发育不良在什么时间治疗才能逆转其病理变化尚无定论。已有研究对髋臼发育不良髋臼软骨的病理变化及其可逆性进行观察,但对股骨头软骨的变化及其时序性与可逆性的研究尚未见报告。由于髋关节内、外侧应力不同,本研究拟分别对不同时段髋臼发育不良兔模型股骨头内、外侧软骨的组织形态学变化和I型胶原、基质金属蛋白酶-13(Matrix metalloproteinase-13, MMP-13)表达情况进行观察,以探讨髋臼发育不良与骨关节炎的相关性,并通过对股骨头退行性变可逆性时间节点的观察为临床对残余髋发育不良治疗时机的选择提供理论依据。
[方法]
选取5周龄新西兰大白兔27只,随机分为A、B、C三组,每组9只。左后肢为实验侧,以石膏管型外固定保持伸膝屈髋位,三组固定时间分别为2周、4周、6周；右后肢为对照侧,不做处理。所有实验兔在固定2周后行骨盆正位片检查,证实造模成功。每组在达到各自固定时间后随机选取5只取材,构成幼兔组a、b、c组；各组另外4只拆除石膏继续喂养至6月龄时取材,构成成兔A、B、C组。股骨头内、外侧软骨应力部位不同,分别进行观察、分析。标本HE常规染色后光镜下进行软骨组织形态学观察,并进行改良Mankin评分；采用免疫组化染色观察Ⅰ型胶原、MMP-13表达情况,通过Image-Pro Plus 6.0软件测量累积光密度值(IOD值)进行定量分析。运用Stata 7软件进行统计分析。采用两样本均数t检验进行实验组与对照组以及同一股骨头内、外侧间的比较。取P<0.05为差异有统计学意义。
[结果]
1.组织形态学观察与改良Mankin评分：幼兔对照组中a、b、c各组均见软骨表面光滑,潮线清楚；实验组中a组见软骨细胞增多,b组见潮线模糊、多层潮线,c组见软骨表面轻度不规则,部分软骨细胞增生成簇。尽管组织形态学观察有所不同,但幼兔a、b、c各组实验组与对照组之间以及内、外侧之间改良Mankin评分均无统计学差异。成兔A、B组实验组与对照组均见部分软骨表面轻度不规则,潮线中断、模糊较多见。实验组与对照组之间以及内、外侧之间改良Mankin评分均无统计学差异；成兔C组对照组软骨表面轻度不规则,细胞排列规则；实验组软骨表面不规则,可见裂隙,细胞明显增多,增殖成簇,潮线模糊。实验组内、外侧改良Mankin评分均比对照组高(P<0.01),内、外侧之间改良Mankin评分无统计学差异。
2.Ⅰ型胶原表达：Ⅰ型胶原表达于软骨细胞胞浆内,在幼兔及成兔各组中均有表达。幼兔各组随固定时间延长表达逐渐增多,幼兔a、b组实验组与对照组比较、外侧与内侧比较均无统计学差异；幼兔c组实验组内、外侧均比对照组表达增多(外侧P=0.0013,内侧P=0.0201),实验组外侧比内侧表达增多(P=0.0185)。成兔A、B组实验组与对照组比较、外侧与内侧比较无统计学差异；成兔C组实验组内、外侧均比对照组表达增多(外侧P=0.0004,内侧P=0.0083),实验组外侧比内侧表达增多(P=0.0043)。
3.MMP-13表达：MMP-13表达于软骨细胞胞浆内,在幼兔及成兔各组中均有表达。幼兔各组随固定时间延长表达逐渐增多,幼兔a组实验组与对照组比较、外侧与内侧比较均无统计学差异；幼兔b、c组实验组内、外侧均比对照组表达增多(P<0.01,c组外侧P<0.05),外侧与内侧比较无统计学差异。成兔A组实验组与对照组比较、外侧与内侧比较无统计学差异；成兔B组实验组外侧比对照组表达增多(P=0.0067),内侧与对照组比较无统计学差异；实验组外侧比内侧表达增多(P=0.0488),对照组外侧与内侧比较无统计学差异；成兔C组实验组内、外侧均比对照组表达增多(外侧P=0.0118,内侧P=0.044),内外侧比较无统计学差异。
[结论]
1.髋臼发育不良股骨头软骨退行性变具有时序性与一定时段的可逆性。
2.髋臼发育不良股骨头软骨退行性变时I型胶原、MMP-13表达增多；MMP-13是反应软骨退变更敏感的指标。
3.股骨头内、外侧应力的差异在一定时段可能导致软骨退行性变出现差异。
[Background and Object]
Developmental dysplasia of the hip (DDH) is one of the common deformities of limbs in children. Most of DDH patients were diagnosed earlierly now, because of early screening during infant. Even the hip development improve after close or open reduction, there are still around 70% patients suffering from residual acetabular dysplasia(RAD), which is potential cause of osteoarthritis(OA) when they are adults. Controversy always exists in terms of the most optimalized age to treat RAD. So far it is unknown that whether the pathophysiological changes in RAD cartilage can be reversible or not. Our previous data suggested that the degeneration of acetabular cartilage in acetabular dysplasia (AD) was time-dependent and reversible. But the changes of femoral head cartilage and the sequence and reversibility of the changes in AD are still unknown. So histomorphological changes, type I collagen and matrix metalloproteinase-13(MMP-13) of femoral head cartilages of serial immature rabbit AD models were observed in this study, in order to study the relevance between AD and OA, and to provide theory evidence for choosing the correct age for treating AD in children by observing the time point of reversibility of femoral head cartilage degeneration in AD.
[Methods]
Twenty seven 5-week-old New Zealand rabbits were randomly divided into three groups, namely A, B, C. And every group owned 9 rabbits. The left hind limb as the experimental side, which was given cast immobilization, maintaining knee extended and hip flexed for 2,4,6 weeks for each group respectively. The right hind limb served as the control side with no treatment. The anteroposterior pelvic radiograph of all rabbits were taken after 2 weeks cast immobilization. The results shows AD models were established. Five rabbits were sacrificed from each group after achieving their own casting time, composing the immature groups a,b and c. And the other four were given cast removal and were sacrificed at 6 months old, composing the mature groups A,B and C. The medial and lateral parts of femoral head cartilages were observed respectively. The morphology of femoral head cartilages was observed using HE staining, and the modified Mankin scores were gotten according to the morphology. Expression of type I collagen and Matrix metalloproteinase-13 (MMP-13) in femoral head cartilages were detected by the Immunohistochemical staining (IHC). Using Image-Pro Prus 6.0 to measure the integrated optical density(IOD). Stata 7 was adopted for statistics. Using two samples t test to compare experimental groups with control groups and medial parts with lateral parts.
[Results]
1. Histomorphological study and modified Mankin scores:
Articular cartilages on control sides had smooth surfaces and tide lines were smooth in immature group a,b and c. On experimental side number of cartilage cells increased in immature group a; Tide line was blurred in immature group b; Cartilage had slightly irregular surface, cartilage cell number increased and a few cell clusters formed in immature group c. No significant difference of the modified Mankin scores in immature group a, b and c was found between experimental side and control side, nor did it between medial part and lateral part. In mature models, articular cartilages had slightly irregular surface, tide lines were blurred and interrupted both on control side and on experimental side in group A and B. No significant difference of the modified Mankin scores in group A and B was found between experimental side and control side, nor did it between medial parts and lateral parts. In mature group C cartilage surfaces were irregular, and there were a few hiatuses in the surfaces on experimental sides, cartilage cell number increased greatly, and the array of cells was disordered; Cell clusters were found frequently on experimental side. Tide lines were blurred. The modified Mankin score in group C experimental side was higher (P< 0.01). But no significant difference was found between medial part and lateral part.
2. The expression of type I collagen in femoral head cartilage of the AD
Type I collagen was expressed in cytochylema in cartilage cells. In immature groups, expression of type I collagen increased gradually after 2,4,6-weeks immobilization. But no significant difference was found between experimental side and control side, nor did it between medial part and lateral part in group a and b. In group c, expression of type I collagen in experimental side is higher both in medial part and in lateral part (lateral part P=0.0013, medial part P=0.0201), and it is highe in lateral part than that in medial part in experimental side (P=0.0185). In mature groups, no significant difference was found between experimental side and control side, nor did it between medial part and lateral part in group A and B. Expression of type I collagen in experimental side is higher both in medial part and in lateral part (lateral part P=0.0004, medial part P=0.0083), and it is higher in lateral part in experimental side (P=0.0043) in group C.
3. The expression of MMP-13 in femoral head cartilage of the AD
MMP-13 was expressed in cytochylema in cartilage cells. In immature groups, expression of MMP-13 increased gradually after 2,4,6-weeks immobilization. No significant difference was found between experimental side and control side, nor did it between medial part and lateral part in group a. Expression of MMP-13 in experimental side was higher both in medial part and in lateral part (P<0.01, lateral part of group c P<0.05), but there was no significant difference between medial part and lateral part both in group b and in group c. In mature groups, no significant difference was found between experimental side and control side, nor did it between medial part and lateral part in group A. Expression of MMP-13 in experimental side was higher only in lateral part (P=0.0067). In medial part no significant difference was found in group B. Expression of MMP-13 in experimental side was higher both in medial part and in lateral part (lateral part P=0.0118, medial part P=0.044), but there was no significant difference between medial part and lateral part in group C.
[Conclusions]
1. Degeneration of femoral head cartilage in the acetabular dysplasia is sequential, and it is reversible in some stage.
2. The expression of type I collagen and MMP-13 in femoral head cartilage in AD is higher when cartilage degenerated. MMP-13 may be a more sensitive monitor indicating cartilage degeneration.
3. The difference of mechanical stress between medial part and lateral part in femoral head may cause difference of cartilage degeneration in some stage.
发育性髋关节发育不良(Developmental dysplasia of the hip, DDH)是小儿常见的四肢畸形之一。随着早期筛查的开展,很多DDH患儿能够得到闭合复位等早期治疗,但其中相当一部分会出现残余髋臼发育不良,以后进展为骨关节炎(Osteoarthritis, OA)。目前对于残余髋臼发育不良治疗时机的选择有不同观点,残余髋臼发育不良在什么时间治疗才能逆转其病理变化尚无定论。已有研究对髋臼发育不良髋臼软骨的病理变化及其可逆性进行观察,但对股骨头软骨的变化及其时序性与可逆性的研究尚未见报告。由于髋关节内、外侧应力不同,本研究拟分别对不同时段髋臼发育不良兔模型股骨头内、外侧软骨的组织形态学变化和I型胶原、基质金属蛋白酶-13(Matrix metalloproteinase-13, MMP-13)表达情况进行观察,以探讨髋臼发育不良与骨关节炎的相关性,并通过对股骨头退行性变可逆性时间节点的观察为临床对残余髋发育不良治疗时机的选择提供理论依据。
[方法]
选取5周龄新西兰大白兔27只,随机分为A、B、C三组,每组9只。左后肢为实验侧,以石膏管型外固定保持伸膝屈髋位,三组固定时间分别为2周、4周、6周；右后肢为对照侧,不做处理。所有实验兔在固定2周后行骨盆正位片检查,证实造模成功。每组在达到各自固定时间后随机选取5只取材,构成幼兔组a、b、c组；各组另外4只拆除石膏继续喂养至6月龄时取材,构成成兔A、B、C组。股骨头内、外侧软骨应力部位不同,分别进行观察、分析。标本HE常规染色后光镜下进行软骨组织形态学观察,并进行改良Mankin评分；采用免疫组化染色观察Ⅰ型胶原、MMP-13表达情况,通过Image-Pro Plus 6.0软件测量累积光密度值(IOD值)进行定量分析。运用Stata 7软件进行统计分析。采用两样本均数t检验进行实验组与对照组以及同一股骨头内、外侧间的比较。取P<0.05为差异有统计学意义。
[结果]
1.组织形态学观察与改良Mankin评分：幼兔对照组中a、b、c各组均见软骨表面光滑,潮线清楚；实验组中a组见软骨细胞增多,b组见潮线模糊、多层潮线,c组见软骨表面轻度不规则,部分软骨细胞增生成簇。尽管组织形态学观察有所不同,但幼兔a、b、c各组实验组与对照组之间以及内、外侧之间改良Mankin评分均无统计学差异。成兔A、B组实验组与对照组均见部分软骨表面轻度不规则,潮线中断、模糊较多见。实验组与对照组之间以及内、外侧之间改良Mankin评分均无统计学差异；成兔C组对照组软骨表面轻度不规则,细胞排列规则；实验组软骨表面不规则,可见裂隙,细胞明显增多,增殖成簇,潮线模糊。实验组内、外侧改良Mankin评分均比对照组高(P<0.01),内、外侧之间改良Mankin评分无统计学差异。
2.Ⅰ型胶原表达：Ⅰ型胶原表达于软骨细胞胞浆内,在幼兔及成兔各组中均有表达。幼兔各组随固定时间延长表达逐渐增多,幼兔a、b组实验组与对照组比较、外侧与内侧比较均无统计学差异；幼兔c组实验组内、外侧均比对照组表达增多(外侧P=0.0013,内侧P=0.0201),实验组外侧比内侧表达增多(P=0.0185)。成兔A、B组实验组与对照组比较、外侧与内侧比较无统计学差异；成兔C组实验组内、外侧均比对照组表达增多(外侧P=0.0004,内侧P=0.0083),实验组外侧比内侧表达增多(P=0.0043)。
3.MMP-13表达：MMP-13表达于软骨细胞胞浆内,在幼兔及成兔各组中均有表达。幼兔各组随固定时间延长表达逐渐增多,幼兔a组实验组与对照组比较、外侧与内侧比较均无统计学差异；幼兔b、c组实验组内、外侧均比对照组表达增多(P<0.01,c组外侧P<0.05),外侧与内侧比较无统计学差异。成兔A组实验组与对照组比较、外侧与内侧比较无统计学差异；成兔B组实验组外侧比对照组表达增多(P=0.0067),内侧与对照组比较无统计学差异；实验组外侧比内侧表达增多(P=0.0488),对照组外侧与内侧比较无统计学差异；成兔C组实验组内、外侧均比对照组表达增多(外侧P=0.0118,内侧P=0.044),内外侧比较无统计学差异。
[结论]
1.髋臼发育不良股骨头软骨退行性变具有时序性与一定时段的可逆性。
2.髋臼发育不良股骨头软骨退行性变时I型胶原、MMP-13表达增多；MMP-13是反应软骨退变更敏感的指标。
3.股骨头内、外侧应力的差异在一定时段可能导致软骨退行性变出现差异。
[Background and Object]
Developmental dysplasia of the hip (DDH) is one of the common deformities of limbs in children. Most of DDH patients were diagnosed earlierly now, because of early screening during infant. Even the hip development improve after close or open reduction, there are still around 70% patients suffering from residual acetabular dysplasia(RAD), which is potential cause of osteoarthritis(OA) when they are adults. Controversy always exists in terms of the most optimalized age to treat RAD. So far it is unknown that whether the pathophysiological changes in RAD cartilage can be reversible or not. Our previous data suggested that the degeneration of acetabular cartilage in acetabular dysplasia (AD) was time-dependent and reversible. But the changes of femoral head cartilage and the sequence and reversibility of the changes in AD are still unknown. So histomorphological changes, type I collagen and matrix metalloproteinase-13(MMP-13) of femoral head cartilages of serial immature rabbit AD models were observed in this study, in order to study the relevance between AD and OA, and to provide theory evidence for choosing the correct age for treating AD in children by observing the time point of reversibility of femoral head cartilage degeneration in AD.
[Methods]
Twenty seven 5-week-old New Zealand rabbits were randomly divided into three groups, namely A, B, C. And every group owned 9 rabbits. The left hind limb as the experimental side, which was given cast immobilization, maintaining knee extended and hip flexed for 2,4,6 weeks for each group respectively. The right hind limb served as the control side with no treatment. The anteroposterior pelvic radiograph of all rabbits were taken after 2 weeks cast immobilization. The results shows AD models were established. Five rabbits were sacrificed from each group after achieving their own casting time, composing the immature groups a,b and c. And the other four were given cast removal and were sacrificed at 6 months old, composing the mature groups A,B and C. The medial and lateral parts of femoral head cartilages were observed respectively. The morphology of femoral head cartilages was observed using HE staining, and the modified Mankin scores were gotten according to the morphology. Expression of type I collagen and Matrix metalloproteinase-13 (MMP-13) in femoral head cartilages were detected by the Immunohistochemical staining (IHC). Using Image-Pro Prus 6.0 to measure the integrated optical density(IOD). Stata 7 was adopted for statistics. Using two samples t test to compare experimental groups with control groups and medial parts with lateral parts.
[Results]
1. Histomorphological study and modified Mankin scores:
Articular cartilages on control sides had smooth surfaces and tide lines were smooth in immature group a,b and c. On experimental side number of cartilage cells increased in immature group a; Tide line was blurred in immature group b; Cartilage had slightly irregular surface, cartilage cell number increased and a few cell clusters formed in immature group c. No significant difference of the modified Mankin scores in immature group a, b and c was found between experimental side and control side, nor did it between medial part and lateral part. In mature models, articular cartilages had slightly irregular surface, tide lines were blurred and interrupted both on control side and on experimental side in group A and B. No significant difference of the modified Mankin scores in group A and B was found between experimental side and control side, nor did it between medial parts and lateral parts. In mature group C cartilage surfaces were irregular, and there were a few hiatuses in the surfaces on experimental sides, cartilage cell number increased greatly, and the array of cells was disordered; Cell clusters were found frequently on experimental side. Tide lines were blurred. The modified Mankin score in group C experimental side was higher (P< 0.01). But no significant difference was found between medial part and lateral part.
2. The expression of type I collagen in femoral head cartilage of the AD
Type I collagen was expressed in cytochylema in cartilage cells. In immature groups, expression of type I collagen increased gradually after 2,4,6-weeks immobilization. But no significant difference was found between experimental side and control side, nor did it between medial part and lateral part in group a and b. In group c, expression of type I collagen in experimental side is higher both in medial part and in lateral part (lateral part P=0.0013, medial part P=0.0201), and it is highe in lateral part than that in medial part in experimental side (P=0.0185). In mature groups, no significant difference was found between experimental side and control side, nor did it between medial part and lateral part in group A and B. Expression of type I collagen in experimental side is higher both in medial part and in lateral part (lateral part P=0.0004, medial part P=0.0083), and it is higher in lateral part in experimental side (P=0.0043) in group C.
3. The expression of MMP-13 in femoral head cartilage of the AD
MMP-13 was expressed in cytochylema in cartilage cells. In immature groups, expression of MMP-13 increased gradually after 2,4,6-weeks immobilization. No significant difference was found between experimental side and control side, nor did it between medial part and lateral part in group a. Expression of MMP-13 in experimental side was higher both in medial part and in lateral part (P<0.01, lateral part of group c P<0.05), but there was no significant difference between medial part and lateral part both in group b and in group c. In mature groups, no significant difference was found between experimental side and control side, nor did it between medial part and lateral part in group A. Expression of MMP-13 in experimental side was higher only in lateral part (P=0.0067). In medial part no significant difference was found in group B. Expression of MMP-13 in experimental side was higher both in medial part and in lateral part (lateral part P=0.0118, medial part P=0.044), but there was no significant difference between medial part and lateral part in group C.
[Conclusions]
1. Degeneration of femoral head cartilage in the acetabular dysplasia is sequential, and it is reversible in some stage.
2. The expression of type I collagen and MMP-13 in femoral head cartilage in AD is higher when cartilage degenerated. MMP-13 may be a more sensitive monitor indicating cartilage degeneration.
3. The difference of mechanical stress between medial part and lateral part in femoral head may cause difference of cartilage degeneration in some stage.
引文
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[2]Herring JA. Developmental dysplasia of the hip. In:Tachdjian's Pediatric Orthopaedics.4th ed. Philadelphia:Saunders,2008:637-770.
[3]Engesaeter IO, Lie SA, Lehmann TG, et al. Neonatal hip instability and risk of total hip replacement in young adulthood:follow-up of 2,218,596 newborns from the Medical Birth Registry of Norway in the Norwegian Arthroplasty Register. Acta Orthop,2008,79(3):321-326.
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[6]Miosge N, Hartmann M, Maelicke C, et al. Expression of collagen type Ⅰ and type Ⅱ in consecutive stages of human osteoarthritis. Histochem Cell Biol,2004, 122(3):229-236.
[7]Andreas L, Eike M, Heiko S, et al:Changes in content and synthesis of collagen types and proteoglycans in osteoarthritis of the knee joint and comparison of quantitative analysis with Photoshop-based image analysis.Arch Orthop Trauma Surg,2010,130:557-564.
[8]Kamekura S, Hoshi K, Shimoaka T, et al. Osteoarthritis development in novel experimental mouse models induced by knee joint instability. Osteoarthritis Cartilage 2005;13:632-41.
[9]Pelletier J-P, Boileau C, Boily M, et al. The protective effect of licofelone on experimental osteoarthritis is correlated with the downregulation of gene expression and protein synthesis of several major cartilage catabolic factors: MMP-13, cathepsin K and aggrecanases. Arthritis Res Ther 2005;7:R1091-102.
[10]Yagi R, McBurney D, Laverty D, et al. Intrajoint comparisons of gene expression patterns in human osteoarthritis suggest a change in chondrocyte phenotype. J Orthop Res 2005;23:1128-38.
[11]陈连旭,余家阔,于长隆.大鼠、兔和人关节软骨组织形态学的比较.中国组织工程研究与临床康复,2007,11(41)：8230-8233.
[12]Ledingham J, Dawson S, Preston B, et al. Radiographic patterns and associations of osteoarthritis of the hip. Ann Rheum Dis,1992,51:1111-1116.
[13]Sakakibara Y, Miura T, Iwata H, et al. Effect of High-Molecular-Weight Sodium Hyaluronate on Immobilized Rabbit Knee. Clin Orthop Relat Res,1994,299, pp. 282-292.
[14]Maroudas A, Bayliss M T, Venn M F. Further studies on the composition of human femoral head cartilage. Ann Rheum Dis,1980,39:514-523.
[15]Anne-Christine BJ, Suzi HM, Erik D, et al. Which elements are involved in reversible and irreversible cartilage degradation in osteoarthritis? Rheumatol Int,2010,30:435-442.
[16]Claassen H, Kampen WU, Kirsch T. Localization of collagens and alkaline phosphatase activity during mineralization and ossification of human first rib cartilage. Histochem Cell Biol,1996,105:213-219.
[17]Yocum SA, Lopresti-Morrow LL, Reeves LM,et al. INHIBITION OF MATRIX METALLOPROTEINASES:THERAPEUTIC APPLICATIONS. (1999)878: 583-586
[18]Brew CJ, Clegg PD, Boot-Handford RP. Gene expression in human chondrocytes in late osteoarthritis is changed in both fibrillated and intact cartilage without evidence of generalised chondrocyte hypertrophy. Ann Rheum Dis,2010;69:234-240.
[19]Neuhold LA, Killar L, Zhao WG, et al. Postnatal expression in hyaline cartilage of constitutively active human collagenase-3 (MMP-13) induces osteoarthritis in mice. OURNAL OF CLINICAL INVESTIGATION,2001,107(1):35-44.
[20]Le Graverand MP, Eggerer J, Vignon E, et al. Assessment of specific mRNA levels in cartilage regions in a lapine model of osteoarthritis. J Orthop Res,2002,20:535-544.
[21]Bluteau G, Gouttenoire J, Conrozier T, et al. Differential gene expression analysis in a rabbit model of osteoarthritis induced by anterior cruciate ligament (ACL) section. Biorheology,2002;39(1-2):247-258.
[22]Hegemann N, Kohn B, Brunnberg L, et al. Biomarkers of joint tissue metabolism in canine osteoarthritic and arthritic joint disorders. Osteoarthritis Cartilage,2002,10(9)：14-21.
[23]Poole AR. An introduction to the pathophysiology of osteoarthritis. Front Biosci, 1999,4:662-670.
[24]Young AA, Smith MM, Smith SM, et al. Regional assessment of articular cartilage gene expression and small proteoglycan metabolism in an animal model of osteoarthritis. Arthritis Res Ther,2005,7(4):R852-R861.
[25]Stefano M, Giovanni F F, Giovanni M, et al. A correlation between knee cartilage degradation observed by arthroseopy and synovial proteinases activities[J]. Clini Biochem,2003,36:295—304.
[26]Sondergaard BC, Henriksen K, Wulf H, et al. Relative contribution of matrix metalloprotease and cysteine protease activities to cytokine-stimulated articular cartilage degradation. Osteoarthr Cartil,2006,14:738-748.
[27]Karsdal MA, Sumer EU, Wulf H, et al. Induction of increased cAMP levels in articular chondrocytes blocks matrix metalloproteinase-mediated cartilage degradation, but not aggrecanase-mediated cartilage degradation. Arthritis Rheum,2007,56:1549-1558.
[28]Karsdal MA, Madsen SH, Christiansen C, et al. Cartilage degradation is fully reversible in the presence of aggrecanase but not matrix metalloproteinase activity. Arthritis Res Ther,2008,10:R63.
[29]Li TY, Ma RX. Increasing thickness and fibrosis of the cartilage in acetabular dysplasia:a rabbit model research. CHINESE MEDICAL JOURNAL, 2010,123(21):3061-3066.
[30]张自明,马瑞雪,吉士俊.实验性髋臼发育不良的病理形态学研究.中国矫形外科杂志,2002,9(5)：480-482.
[31]Shimogaki K, Yasunaga Y, Ochi M. A histological study of articular cartilage after rotational acetabular osteotomy for hip dysplasia. J Bone and Joint Sur(Br), 2005,87(7):1019-1023.
[32]Raab P, Lohr J, Krauspe R. Remodeling of the acetabulum after experimental hip joint dislocation:an animal experiment study of the rabbit. Z Orthop Hire Grenzgeb,1998,136:519-524.
[33]Mav AB, Brand, Richard KI, et al. Cumulative hip contactstress predicts osteoarthritis in DDH. Clin Orthop Relat Res,2008,466(4):884-891.
[34]陈百成,张静,2004.骨关节炎.北京：人民卫生出版社,199.
[1]Watanabe H. Aggrecan and its chondroitin sulfate in cartilage[J]. Seikagaku, 2008,80(1):28-32.
[2]Fosang AJ, Rogerson FM, East CJ, et al. ADAMTS- 5:The story so far[J]. Eur Cell Mater,2008,15(1):11-26.
[3]Pratta MA, Yao WQ, Decicco C, et al. Aggrecan protects cartilage collagen from proteolytic cleavage [J]. J Biol Chem,2003,278(46):45539-45545.
[4]Stanton, H. et al. ADAMTS-5 is the major aggrecanase in mouse cartilage in vivo and in vitro[J]. Nature,2005,434,648-652.
[5]Glasson SS, Askew R, Sheppard B, et al. Characterization of and osteoarthritis susceptibility in ADAMTS-4-knockout mice[J]. Arthritis Rheum.2004,50, 2547-2558.
[6]Gendron C, Kashiwagi M, Lim NH, et al. Proteolytic activities of human ADAMTS-5-Comparative studies with ADAMTS -4 [J]. J Biol Chem,2007, 282(25):18294-18306.
[7]Lorenzo P, Bayliss MT, Heinegard, D. Altered patterns and synthesis of extracellular matrix macromolecules in early osteoarthritis[J]. Matrix Biol,2004, 23,381-391.
[8]Fang C, Johnson D, Leslie MP. et al. Tissue distribution and measurement of cartilage oligomeric matrix protein in patients with magnetic resonance imaging detected bone bruises after acute anterior cruciate ligament tears [J]. J Orthop Res, 2001,19,634-641.
[9]Arokoski JPA, Hyttinen MM, Lapvetelainen T, et al. Decreased birefringence of the superficial zone collagen network in the canine knee (stifle) articular cartilage after long distance running training, detected by quantitative polarised light microscopy. Ann Rheum Dis.1996,55,253-264.
[10]Frisbie DD, Al-Sobayil F, Billinghurst RC, et al. Changes in synovial fluid and serum biomarkers with exercise and early osteoarthritis in horses[J]. Osteoarthritis and Cartilage,2008,16,1196-1204.
[11]Matyas JR, Atley L, Ionescu M. Analysis of cartilage biomarkers in the early phases of canine osteoarthritis[J]. Arthritis and Rheumatism,2003,50,542-543.
[12]Innes JF, Little CB, Hughes CE, et al. Products resulting from cleavage of the interglobular domain of aggrecan in samples of synovial fluid collected from dogs with early- and late-stage osteoarthritis. American Journal of Veterinary Research, 2005,66,1679-1685.
[13]Sharif M, Kirwan J, Charni N, et al. A 5-yr longitudinal study of type ⅡA collagen synthesis and total type II collagen degradation in patients with knee osteoarthritis-association with disease progression. Rheumatology,2007,46, 938-943.
[14]Cibere J, Zhang H, Garnero P, et al. Association of biomarkers with pre-radiographically defined and radiographically defined knee osteoarthritis in a population-based study. Arthritis Rheum,2009,60(5):1372-80.
[15]Vaughan L, Mendler M, Huber S. et al. D-periodic distribution of collagen type IX along cartilage fibrils. J Cell Biol.1988,106,991-997.
[16]Eyre DR, Pietka T, Weis MA, et al. Covalent cross-linking of the NC1 domain of collagen type IX to collagen type Ⅱ in cartilage. J Biol Chem.2004,279, 2568-2574.
[17]Danfelter M, Onnerfjord P, Heinegard, D. Fragmentation of proteins in cartilage treated with interleukin-1:specific cleavage of type IX collagen by matrix metalloproteinase 13 releases the NC4 domain. J Biol Chem.2007,282, 36933-36941.
[18]Heinegard D, Saxne T. The role of the cartilage matrix in osteoarthritis. Nat Rev Rheumatol.2011,7,50-56.
[19]Halasz K, Kassner A, Morgelin M, et al. COMP acts as a catalyst in collagen fibrillogenesis. J Biol Chem.2007,282,31166-31173.
[20]Thur J, Rosenberg K, Nitsche DP, et al. Mutations in cartilage oligomeric matrix protein causing pseudoachondroplasia and multiple epiphyseal dysplasia affect binding of calcium and collagen Ⅰ, Ⅱ, and IX. J Biol Chem.2001,276, 6083-6092.
[21]Heinegard D. Proteoglycans and more-from molecules to biology. Int J Exp Pathol.2009,90,575-586.
[22]Chaganti RK, Kelman A, Lui L, et al. Change in serum measurements of cartilage oligomeric matrix protein and association with the development and worsening of radiographic hip osteoarthritis. Osteoarthritis and Cartilage,2008,16, 566-571.
[23]Petersson IF, Boegard T, Svensson B, et al. Changes in cartilage and bone metabolism identified by serum markers in early osteoarthritis of the knee joint. British Journal of Rheumatology,1998,37,46-50.
[24]Heathfield TF, Onnerfjord P, Dahlberg L, et al. Cleavage of fibromodulin in cartilage explants involves removal of the N-terminal tyrosine sulfate-rich region by proteolysis at a site that is sensitive to matrix metalloproteinase-13. J Biol Chem,2004,279,6286-6295.
[25]Aigner T, Kurz B, Fukui N, et al. Roles of chondrocytes in the pathogenesis of osteoarthritis. Curr Opin Rheumatol,2002,14:578-584
[26]Goldring MB. Update on the biology of the chondrocyte and new approaches to treating cartilage diseases. Best Pract Res Clin Rheumatol,2006,20:1003-1025.
[27]Valcourt U, Gouttenoire J, Aubert-Foucher E, et al. Alternative splicing of type Ⅱ procollagen pre-mRNA in chondrocytes is oppositely regulated by BMP-2 and TGF-[beta]1. FEBS Lett,2003,545:115-119.
[28]Pfander D, Swoboda B, Kirsch T. Expression of early and late differentiation markers (proliferating cell nuclear antigen, Syndecan-3, Annexin VI, and Alkaline Phosphatase) by human osteoarthritic chondrocytes. Am J Pathol,2001, 159:1777-1783
[29]Benya P, Shaffer JD. Dedifferentiated chondrocytes re-express the differentiated collagen phenotype when cultured in agarose gels. Cell,1982,30, 215-224.
[30]Tew SR, Hardingham TE. Regulation of SOX9 mRNA in human articular chondrocytes involving p38 MAPK activation and mRNA stabilization. J Biol Chem.2006,281,39471-39479.
[31]Tew SR, Murdoch AD, Rauchenberg RP, et al. Cellular methods in cartilage research:primary human chondrocytes in culture and chondrogenesis in human bone marrow stem cells. Methods,2008,45,2-9.
[32]Katapodi T, Tew SR, Hardingham TE. Assembly of cartilage matrix by osteoarthritic human articular chondrocytes on Hyalograft matrices varies with donor, but is enhanced in hypoxic conditions. Biomaterials,2009,30,535-540.
[33]Tew SR, Li Y, Pothacharoen P, et al. Retroviral transduction with SOX9 enhances re-expression of the chondrocyte phenotype in passaged osteoarthritic human articular chondrocytes. Osteoarthr. Cartil.,2005,13,80-89.
[34]Sondergaard BC, Henriksen K, Wulf H, et al. Relative contribution of matrix metalloprotease and cysteine protease activities to cytokine-stimulated articular cartilage degradation. Osteoarthr Cartil,2006,14:738-748
[35]Karsdal MA, Sumer EU, Wulf H, et al. Induction of increased cAMP levels in articular chondrocytes blocks matrix metalloproteinase-mediated cartilage degradation, but not aggrecanase-mediated cartilage degradation. Arthritis Rheum,2007,56:1549-1558
[36]Karsdal MA, Madsen SH, Christiansen C, et al. Cartilage degradation is fully reversible in the presence of aggrecanase but not matrix metalloproteinase activity. Arthritis Res Ther,2008,10:R63
[37]Stoop R, van der Kraan PM, Buma P, et al. Denaturation of type Ⅱ collagen in articular cartilage in experimental murine arthritis. Evidence for collagen degradation in both reversible and irreversible cartilage damage. J Pathol,1999,188:329-337.
[38]Van Meurs JB, van Lent PL, Holthuysen AE, et al. Kinetics of aggrecanase- and metalloproteinase-induced neoepitopes in various stages of cartilage destruction in murine arthritis. Arthritis Rheum,1999,42:1128-1139.
[2]Herring JA. Developmental dysplasia of the hip. In:Tachdjian's Pediatric Orthopaedics.4th ed. Philadelphia:Saunders,2008:637-770.
[3]Engesaeter IO, Lie SA, Lehmann TG, et al. Neonatal hip instability and risk of total hip replacement in young adulthood:follow-up of 2,218,596 newborns from the Medical Birth Registry of Norway in the Norwegian Arthroplasty Register. Acta Orthop,2008,79(3):321-326.
[4]Pfander D,Rahmanzadeh R,Scheller EE. Presence and distribution of collagen Ⅱ,collagen Ⅰ,fibronectin and tenascin in rabbit normal and osteoarthritic cartilage. J Rheumatol,1999,26:386-394.
[5]Marlovits S, Hombauer M, Truppe M, et al. Changes in the ratio of type-Ⅰ and type-Ⅱ collagen expression during monolayer culture of human chondrocytes. J Bone Joint Surg Br,2004,86:286-295.
[6]Miosge N, Hartmann M, Maelicke C, et al. Expression of collagen type Ⅰ and type Ⅱ in consecutive stages of human osteoarthritis. Histochem Cell Biol,2004, 122(3):229-236.
[7]Andreas L, Eike M, Heiko S, et al:Changes in content and synthesis of collagen types and proteoglycans in osteoarthritis of the knee joint and comparison of quantitative analysis with Photoshop-based image analysis.Arch Orthop Trauma Surg,2010,130:557-564.
[8]Kamekura S, Hoshi K, Shimoaka T, et al. Osteoarthritis development in novel experimental mouse models induced by knee joint instability. Osteoarthritis Cartilage 2005;13:632-41.
[9]Pelletier J-P, Boileau C, Boily M, et al. The protective effect of licofelone on experimental osteoarthritis is correlated with the downregulation of gene expression and protein synthesis of several major cartilage catabolic factors: MMP-13, cathepsin K and aggrecanases. Arthritis Res Ther 2005;7:R1091-102.
[10]Yagi R, McBurney D, Laverty D, et al. Intrajoint comparisons of gene expression patterns in human osteoarthritis suggest a change in chondrocyte phenotype. J Orthop Res 2005;23:1128-38.
[11]陈连旭,余家阔,于长隆.大鼠、兔和人关节软骨组织形态学的比较.中国组织工程研究与临床康复,2007,11(41)：8230-8233.
[12]Ledingham J, Dawson S, Preston B, et al. Radiographic patterns and associations of osteoarthritis of the hip. Ann Rheum Dis,1992,51:1111-1116.
[13]Sakakibara Y, Miura T, Iwata H, et al. Effect of High-Molecular-Weight Sodium Hyaluronate on Immobilized Rabbit Knee. Clin Orthop Relat Res,1994,299, pp. 282-292.
[14]Maroudas A, Bayliss M T, Venn M F. Further studies on the composition of human femoral head cartilage. Ann Rheum Dis,1980,39:514-523.
[15]Anne-Christine BJ, Suzi HM, Erik D, et al. Which elements are involved in reversible and irreversible cartilage degradation in osteoarthritis? Rheumatol Int,2010,30:435-442.
[16]Claassen H, Kampen WU, Kirsch T. Localization of collagens and alkaline phosphatase activity during mineralization and ossification of human first rib cartilage. Histochem Cell Biol,1996,105:213-219.
[17]Yocum SA, Lopresti-Morrow LL, Reeves LM,et al. INHIBITION OF MATRIX METALLOPROTEINASES:THERAPEUTIC APPLICATIONS. (1999)878: 583-586
[18]Brew CJ, Clegg PD, Boot-Handford RP. Gene expression in human chondrocytes in late osteoarthritis is changed in both fibrillated and intact cartilage without evidence of generalised chondrocyte hypertrophy. Ann Rheum Dis,2010;69:234-240.
[19]Neuhold LA, Killar L, Zhao WG, et al. Postnatal expression in hyaline cartilage of constitutively active human collagenase-3 (MMP-13) induces osteoarthritis in mice. OURNAL OF CLINICAL INVESTIGATION,2001,107(1):35-44.
[20]Le Graverand MP, Eggerer J, Vignon E, et al. Assessment of specific mRNA levels in cartilage regions in a lapine model of osteoarthritis. J Orthop Res,2002,20:535-544.
[21]Bluteau G, Gouttenoire J, Conrozier T, et al. Differential gene expression analysis in a rabbit model of osteoarthritis induced by anterior cruciate ligament (ACL) section. Biorheology,2002;39(1-2):247-258.
[22]Hegemann N, Kohn B, Brunnberg L, et al. Biomarkers of joint tissue metabolism in canine osteoarthritic and arthritic joint disorders. Osteoarthritis Cartilage,2002,10(9)：14-21.
[23]Poole AR. An introduction to the pathophysiology of osteoarthritis. Front Biosci, 1999,4:662-670.
[24]Young AA, Smith MM, Smith SM, et al. Regional assessment of articular cartilage gene expression and small proteoglycan metabolism in an animal model of osteoarthritis. Arthritis Res Ther,2005,7(4):R852-R861.
[25]Stefano M, Giovanni F F, Giovanni M, et al. A correlation between knee cartilage degradation observed by arthroseopy and synovial proteinases activities[J]. Clini Biochem,2003,36:295—304.
[26]Sondergaard BC, Henriksen K, Wulf H, et al. Relative contribution of matrix metalloprotease and cysteine protease activities to cytokine-stimulated articular cartilage degradation. Osteoarthr Cartil,2006,14:738-748.
[27]Karsdal MA, Sumer EU, Wulf H, et al. Induction of increased cAMP levels in articular chondrocytes blocks matrix metalloproteinase-mediated cartilage degradation, but not aggrecanase-mediated cartilage degradation. Arthritis Rheum,2007,56:1549-1558.
[28]Karsdal MA, Madsen SH, Christiansen C, et al. Cartilage degradation is fully reversible in the presence of aggrecanase but not matrix metalloproteinase activity. Arthritis Res Ther,2008,10:R63.
[29]Li TY, Ma RX. Increasing thickness and fibrosis of the cartilage in acetabular dysplasia:a rabbit model research. CHINESE MEDICAL JOURNAL, 2010,123(21):3061-3066.
[30]张自明,马瑞雪,吉士俊.实验性髋臼发育不良的病理形态学研究.中国矫形外科杂志,2002,9(5)：480-482.
[31]Shimogaki K, Yasunaga Y, Ochi M. A histological study of articular cartilage after rotational acetabular osteotomy for hip dysplasia. J Bone and Joint Sur(Br), 2005,87(7):1019-1023.
[32]Raab P, Lohr J, Krauspe R. Remodeling of the acetabulum after experimental hip joint dislocation:an animal experiment study of the rabbit. Z Orthop Hire Grenzgeb,1998,136:519-524.
[33]Mav AB, Brand, Richard KI, et al. Cumulative hip contactstress predicts osteoarthritis in DDH. Clin Orthop Relat Res,2008,466(4):884-891.
[34]陈百成,张静,2004.骨关节炎.北京：人民卫生出版社,199.
[1]Watanabe H. Aggrecan and its chondroitin sulfate in cartilage[J]. Seikagaku, 2008,80(1):28-32.
[2]Fosang AJ, Rogerson FM, East CJ, et al. ADAMTS- 5:The story so far[J]. Eur Cell Mater,2008,15(1):11-26.
[3]Pratta MA, Yao WQ, Decicco C, et al. Aggrecan protects cartilage collagen from proteolytic cleavage [J]. J Biol Chem,2003,278(46):45539-45545.
[4]Stanton, H. et al. ADAMTS-5 is the major aggrecanase in mouse cartilage in vivo and in vitro[J]. Nature,2005,434,648-652.
[5]Glasson SS, Askew R, Sheppard B, et al. Characterization of and osteoarthritis susceptibility in ADAMTS-4-knockout mice[J]. Arthritis Rheum.2004,50, 2547-2558.
[6]Gendron C, Kashiwagi M, Lim NH, et al. Proteolytic activities of human ADAMTS-5-Comparative studies with ADAMTS -4 [J]. J Biol Chem,2007, 282(25):18294-18306.
[7]Lorenzo P, Bayliss MT, Heinegard, D. Altered patterns and synthesis of extracellular matrix macromolecules in early osteoarthritis[J]. Matrix Biol,2004, 23,381-391.
[8]Fang C, Johnson D, Leslie MP. et al. Tissue distribution and measurement of cartilage oligomeric matrix protein in patients with magnetic resonance imaging detected bone bruises after acute anterior cruciate ligament tears [J]. J Orthop Res, 2001,19,634-641.
[9]Arokoski JPA, Hyttinen MM, Lapvetelainen T, et al. Decreased birefringence of the superficial zone collagen network in the canine knee (stifle) articular cartilage after long distance running training, detected by quantitative polarised light microscopy. Ann Rheum Dis.1996,55,253-264.
[10]Frisbie DD, Al-Sobayil F, Billinghurst RC, et al. Changes in synovial fluid and serum biomarkers with exercise and early osteoarthritis in horses[J]. Osteoarthritis and Cartilage,2008,16,1196-1204.
[11]Matyas JR, Atley L, Ionescu M. Analysis of cartilage biomarkers in the early phases of canine osteoarthritis[J]. Arthritis and Rheumatism,2003,50,542-543.
[12]Innes JF, Little CB, Hughes CE, et al. Products resulting from cleavage of the interglobular domain of aggrecan in samples of synovial fluid collected from dogs with early- and late-stage osteoarthritis. American Journal of Veterinary Research, 2005,66,1679-1685.
[13]Sharif M, Kirwan J, Charni N, et al. A 5-yr longitudinal study of type ⅡA collagen synthesis and total type II collagen degradation in patients with knee osteoarthritis-association with disease progression. Rheumatology,2007,46, 938-943.
[14]Cibere J, Zhang H, Garnero P, et al. Association of biomarkers with pre-radiographically defined and radiographically defined knee osteoarthritis in a population-based study. Arthritis Rheum,2009,60(5):1372-80.
[15]Vaughan L, Mendler M, Huber S. et al. D-periodic distribution of collagen type IX along cartilage fibrils. J Cell Biol.1988,106,991-997.
[16]Eyre DR, Pietka T, Weis MA, et al. Covalent cross-linking of the NC1 domain of collagen type IX to collagen type Ⅱ in cartilage. J Biol Chem.2004,279, 2568-2574.
[17]Danfelter M, Onnerfjord P, Heinegard, D. Fragmentation of proteins in cartilage treated with interleukin-1:specific cleavage of type IX collagen by matrix metalloproteinase 13 releases the NC4 domain. J Biol Chem.2007,282, 36933-36941.
[18]Heinegard D, Saxne T. The role of the cartilage matrix in osteoarthritis. Nat Rev Rheumatol.2011,7,50-56.
[19]Halasz K, Kassner A, Morgelin M, et al. COMP acts as a catalyst in collagen fibrillogenesis. J Biol Chem.2007,282,31166-31173.
[20]Thur J, Rosenberg K, Nitsche DP, et al. Mutations in cartilage oligomeric matrix protein causing pseudoachondroplasia and multiple epiphyseal dysplasia affect binding of calcium and collagen Ⅰ, Ⅱ, and IX. J Biol Chem.2001,276, 6083-6092.
[21]Heinegard D. Proteoglycans and more-from molecules to biology. Int J Exp Pathol.2009,90,575-586.
[22]Chaganti RK, Kelman A, Lui L, et al. Change in serum measurements of cartilage oligomeric matrix protein and association with the development and worsening of radiographic hip osteoarthritis. Osteoarthritis and Cartilage,2008,16, 566-571.
[23]Petersson IF, Boegard T, Svensson B, et al. Changes in cartilage and bone metabolism identified by serum markers in early osteoarthritis of the knee joint. British Journal of Rheumatology,1998,37,46-50.
[24]Heathfield TF, Onnerfjord P, Dahlberg L, et al. Cleavage of fibromodulin in cartilage explants involves removal of the N-terminal tyrosine sulfate-rich region by proteolysis at a site that is sensitive to matrix metalloproteinase-13. J Biol Chem,2004,279,6286-6295.
[25]Aigner T, Kurz B, Fukui N, et al. Roles of chondrocytes in the pathogenesis of osteoarthritis. Curr Opin Rheumatol,2002,14:578-584
[26]Goldring MB. Update on the biology of the chondrocyte and new approaches to treating cartilage diseases. Best Pract Res Clin Rheumatol,2006,20:1003-1025.
[27]Valcourt U, Gouttenoire J, Aubert-Foucher E, et al. Alternative splicing of type Ⅱ procollagen pre-mRNA in chondrocytes is oppositely regulated by BMP-2 and TGF-[beta]1. FEBS Lett,2003,545:115-119.
[28]Pfander D, Swoboda B, Kirsch T. Expression of early and late differentiation markers (proliferating cell nuclear antigen, Syndecan-3, Annexin VI, and Alkaline Phosphatase) by human osteoarthritic chondrocytes. Am J Pathol,2001, 159:1777-1783
[29]Benya P, Shaffer JD. Dedifferentiated chondrocytes re-express the differentiated collagen phenotype when cultured in agarose gels. Cell,1982,30, 215-224.
[30]Tew SR, Hardingham TE. Regulation of SOX9 mRNA in human articular chondrocytes involving p38 MAPK activation and mRNA stabilization. J Biol Chem.2006,281,39471-39479.
[31]Tew SR, Murdoch AD, Rauchenberg RP, et al. Cellular methods in cartilage research:primary human chondrocytes in culture and chondrogenesis in human bone marrow stem cells. Methods,2008,45,2-9.
[32]Katapodi T, Tew SR, Hardingham TE. Assembly of cartilage matrix by osteoarthritic human articular chondrocytes on Hyalograft matrices varies with donor, but is enhanced in hypoxic conditions. Biomaterials,2009,30,535-540.
[33]Tew SR, Li Y, Pothacharoen P, et al. Retroviral transduction with SOX9 enhances re-expression of the chondrocyte phenotype in passaged osteoarthritic human articular chondrocytes. Osteoarthr. Cartil.,2005,13,80-89.
[34]Sondergaard BC, Henriksen K, Wulf H, et al. Relative contribution of matrix metalloprotease and cysteine protease activities to cytokine-stimulated articular cartilage degradation. Osteoarthr Cartil,2006,14:738-748
[35]Karsdal MA, Sumer EU, Wulf H, et al. Induction of increased cAMP levels in articular chondrocytes blocks matrix metalloproteinase-mediated cartilage degradation, but not aggrecanase-mediated cartilage degradation. Arthritis Rheum,2007,56:1549-1558
[36]Karsdal MA, Madsen SH, Christiansen C, et al. Cartilage degradation is fully reversible in the presence of aggrecanase but not matrix metalloproteinase activity. Arthritis Res Ther,2008,10:R63
[37]Stoop R, van der Kraan PM, Buma P, et al. Denaturation of type Ⅱ collagen in articular cartilage in experimental murine arthritis. Evidence for collagen degradation in both reversible and irreversible cartilage damage. J Pathol,1999,188:329-337.
[38]Van Meurs JB, van Lent PL, Holthuysen AE, et al. Kinetics of aggrecanase- and metalloproteinase-induced neoepitopes in various stages of cartilage destruction in murine arthritis. Arthritis Rheum,1999,42:1128-1139.