Metabolic effects of X-ray irradiation on adult human articular chondrocytes

There have been few reports regarding the metabolic effects of X-ray irradiation on adult human articular chondrocytes. The purpose of this study was to evaluate whether exposure to X-ray irradiation during tumor surgery can cause impaired metabolism in adult articular cartilage. To achieve this we exposed cultured chondrocytes isolated from normal or degenerated cartilage to varying doses of X-ray irradiation, then measured apoptosis, and the production of chondroitin sulfates (CS), prostaglandin E2 (PGE2) and p38 mitogen-activated protein kinase (MAPK) in these cells. The number of apoptotic cells was not affected by irradiation in chondrocytes from normal or degenerated cartilage. Likewise, the production of C6S and C4S was not altered by irradiation in either group. The concentration of PGE2 in non-degenerated chondrocyte cultures did not change with radiation in a dose-dependent manner. However, the concentration of PGE2 in degenerated chondrocytes increased in a radiation dose-dependent manner. Irradiation at 10 Gy, in degenerated chondrocytes, induced remarkable activation of p38. This suggests that it is important to consider whether there is an osteoarthritic joint in the area that is to receive radiation therapy during tumor surgery.     

Hedgehog信号通路阻断剂环巴胺体外对佐剂性关节炎大鼠的关节软骨细胞增殖的影响

目的探讨Hedgehog(Hh)信号通路抑制剂环巴胺体外对佐剂性关节炎大鼠(AA)模型的关节软骨细胞增殖的影响和部分机制。方法弗氏完全佐剂诱导AA大鼠,测量关节炎指数和继发性足肿胀度,HE染色观察两组软骨组织生长情况;取AA大鼠踝关节软骨组织,采用胰蛋白酶-胶原酶法分离、培养、鉴定,环巴胺(0、0.05、0.5、5、20μmol/L)体外给药,MTT法检测AA大鼠踝关节软骨细胞增殖,Annexin V-FITC/PI双染检测AA大鼠踝关节软骨细胞凋亡,Western blotting检测AA大鼠踝关节软骨细胞Shh、Ptch1、Gli1的蛋白表达。结果弗氏完全佐剂诱导后,与正常大鼠相比,AA大鼠关节炎指数和继发性足肿胀度明显升高,HE染色显示,AA大鼠踝关节软骨组织有破坏;甲苯胺蓝和Ⅱ型胶原鉴定体外成功培养AA大鼠踝关节软骨细胞;体外给药环巴胺(0.05、0.5、5、20μmol/L)可升高AA模型关节软骨细胞增殖,流式细胞检测结果显示,环巴胺能降低AA模型软骨细胞凋亡率;与未用环巴胺组相比,环巴胺(0.5、5、20μmol/L)给药对AA软骨细胞中Hh信号通路相关蛋白(Shh、Ptch1、Gli1)表达显著下降。结论弗氏完全佐剂诱导建立AA大鼠模型成立,体外给药环巴胺可抑制AA大鼠软骨细胞的增殖,抑制软骨细胞的凋亡,该作用与抑制AA大鼠软骨细胞Hh信号有关。     

关节腔内骨髓间充质干细胞与同种异体骨的共培养

文章快速阅读：  文题释义： 局部微环境：在将构建的组织工程软骨植入局部进行修复治疗的过程中,会受到局部微环境的较大影响。局部的实际理化环境与各种生长因子,以及力学刺激等均会对组织工程软骨产生极大的影响,并直接影响到软骨修复效果。为此,在进行组织工程软骨构建的时候,可以尝试通过一定的方式,利用各种理化因子和局部血运等因素以更快的速度获得质量更好的组织工程软骨。 同种异体骨：经去抗原免疫、深低温冷冻等处理,抗原性极低,且具有良好的孔隙结构和生物相容性,可以为种子细胞的生长提供所需的空间,是一种十分理想的支架材料。 摘要 背景：构建组织工程软骨的时候,同种异体骨与骨髓间充质干细胞是常用的支架材料和种子细胞,以往大多采用体外培养的方式。膝关节内游离体可以长期存在于关节腔中,并维持一定的软骨组织学特性。因此,关节腔可能为软骨细胞的生长和发育提供良好的环境条件。 目的：探讨在关节腔内骨髓间充质干细胞与同种异体骨复合培养的效果。 方法：纳入5只新西兰新生白兔进行骨髓间充质干细胞分离与培养,利用1只成年新西兰白兔制备同种异体骨,进行骨髓间充质干细胞与同种异体骨复合。实验分组：腔内培养组将骨髓间充质干细胞与同种异体骨复合物培养于动物关节腔内,正常对照组设为同腔内正常软骨,体外培养组实施常规体外培养。培养4,8,12周进行组织学苏木精-伊红染色观察及Ⅱ型胶原免疫组织化学染色观察。 结果与结论：①培养12周进行苏木精-伊红染色和观察,正常对照组细胞质和软骨基质出现红染,细胞核出现蓝染,软骨细胞按照一定的方向呈紧密状有序排列。腔内培养组细胞质和软骨基质出现红染,细胞核出现蓝染,支架材料基本吸收。软骨细胞长入支架之中,细胞按照一定应力方向排列,且形态变小。体外培养组软骨细胞出现大量增殖,但呈无序状排列;②经免疫组织化学染色和观察,计数可得,随着培养时间的推移,腔内培养组的A值呈现出不断上升的情况,体外培养组和正常对照组均未出现明显的改变。且培养4,8,12周,正常对照组和腔内培养组的A值均显著高于体外培养组(P < 0.05)。培养4,8周,腔内培养组的A值均显著低于正常对照组(P < 0.05)。但培养12周,腔内培养组与正常对照组A值差异无显著性意义(P > 0.05);③实验结果表明,在体外和关节腔内环境下,均可以利用同种异体骨与骨髓间充质干细胞复合培养获得组织工程软骨,且关节腔内培养可以获得更好的培养效果。  中国组织工程研究杂志出版内容重点： 干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程 ORCID: 0000-0001-6799-7931(高峰光)     

Regeneration of hyaline articular cartilage with irradiated transforming growth factor beta1-producing fibroblasts

The regeneration of hyaline articular cartilage by cell-mediated gene therapy using transforming growth factor beta(1) (TGF-beta(1))-producing fibroblasts (NIH 3T3-TGF-beta(1)) has been reported previously. In this study, we investigated whether TGF-beta(1)-producing fibroblasts irradiated with a lethal dose of radiation are still capable of inducing the regeneration of hyaline articular cartilage. NIH 3T3TGF-beta(1) fibroblasts were exposed to doses of 20, 40, or 80 Gy, using a irradiator, and then injected into artificially made partial defects on the femoral condyle of rabbit knee joints. The rabbits were killed 3 or 6 weeks postinjection and hyaline articular cartilage regeneration was evaluated by histological and immunohistochemical staining (n = 5 per each group). Irradiated NIH 3T3-TGFbeta(1) fibroblasts started to die rapidly 3 days after irradiation; moreover, the kinetics of their viability were similar regardless of the radiation intensity. TGF-beta1 expression, measured by ELISA, showed that the TGF-beta(1) protein produced from the irradiated cells peaked 5 days after irradiation and thereafter declined rapidly. Complete filling of the defect with reparative tissue occurred in all the groups, although variations were observed in terms of the nature of the repair tissue. Histological and immunohistochemical staining of the repair tissue showed that the tissue newly formed by irradiated NIH 3T3-TGF-beta(1) fibroblasts after exposure to 20 Gy had hyaline cartilage-like characteristics, as was observed in the nonirradiated controls. On the other hand, the repair tissue formed by NIH 3T3-TGF-beta(1) fibroblasts irradiated with 40 or 80 Gy showed more fibrous cartilage-like tissue. These results suggest that TGF-beta(1)-producing fibroblasts irradiated up to a certain level of lethal dose (i.e., 20 Gy) are able to induce normal-appearing articular cartilage in vivo. Therefore, irradiated heterologous cell-mediated TGF-beta(1) gene therapy may be clinically useful and an efficient method of regenerating hyaline articular cartilage.     

Hydrogen peroxide induces apoptosis of chondrocytes; involvement of calcium ion and extracellular signal-regulated protein kinase

OBJECTIVE: Recent observations demonstrated that reactive oxygen species facilitate cartilage degradation. We demonstrated that hydrogen peroxide (H2O2) caused inhibition of proteoglycan synthesis, induction of apoptosis and stimulation of extracellular signal-regulated protein kinase (ERK) of the chondrocytes (Inflamm Res 48: 399-403, 1999). To determine whether activation of ERK is involved in the induction of chondrocyte apoptosis, we examined the signal transduction pathways in this hydrogen peroxide induced apoptosis. DESIGN: Bovine articular chondrocytes were cultured. To determine the induction of apoptosis, Annexin V staining and terminal deoxynucleotidyl transferase were used. The activity of caspase-3 was measured using an apopain assay kit. Intracellular Ca2+ imaging was observed after fura2-AM loading. RESULTS: Hydrogen peroxide enhanced annexin V positive apoptotic cells and caspase-3 activity, which is an executor of apoptosis. Hydrogen peroxide also enhanced intracellular Ca2+ and preincubation with the intracellular Ca2+ chelator protected chondrocytes against hydrogen peroxide-induced cell apoptosis, indicating that an increase in the cytosolic Ca2+ plays a decisive role in this action. When ERK activity was blocked with geldanamycin and PD098059, increased apoptosis was evident. CONCLUSION: Hydrogen peroxide induces chondrocyte apoptosis via Ca2+ signaling, and ERK is involved in these signal transduction pathways.     

流式细胞术定量检测细胞凋亡3种方法的比较研究

目的：探讨流式细胞术定量检测细胞凋亡３种方法的价值。方法：同时使用ＰＩ染色，ＴＵＮＥＬ及Ａｎｎｅｘｉｎ Ｖ／ＰＩ３壹量检测地塞米松处理小鼠的胸腺细胞凋亡发生率。结果：ＰＩ染色，Ａｎｎｅｘｉｎ Ｖ／ＰＩ，ＴＵＮＥＬ３种方法凋亡检出率分别为２７．１９％，３２．２８％，５０．１７％，两者之间均有显著差异。     

紫外线对角质细胞线粒体功能及凋亡的影响研究

目的： 分析紫外线（UV）照射对HaCaT角质细胞系线粒体功能及凋亡的影响。 方法： 以紫外线低剂量（UVA2J/cm2，UVB10mJ/cm2）和高剂量（UVA6J/cm2，UVB30mJ/cm2）照射HaCaT细胞，继续培养15 h，用流式细胞仪检测线粒体膜电位（△ψm）、线粒体质量（mitochondrial mass）；使用碘化丙啶（PI）进行DNA染色并用流式细胞仪检测亚二倍体分析凋亡，以及进行Annexin V-FITC与PI共染色，用激光共聚焦显微镜观察细胞凋亡情况。 结果： HaCaT细胞经紫外线照射后，△ψm下降的细胞比例随着照射剂量的增加而增加，对照组、低剂量组及高剂量组分别为7.94%±1.02%、25.87%±4.55%、39.27%±5.32%；线粒体质量降低的细胞比例同样随着照射剂量的增加而增加，对照组、低剂量组以及高剂量组分别为15.19%±1.58%、40.36%±4.41%、68.79%±5.46%。用PI检测DNA含量所产生的亚二倍体峰观测凋亡率，对照组、低剂量组以及高剂量组凋亡率分别为1.82%±0.51%、30.16%±5.47%、58.49%±5.98%。用Annexin V-FITC/PI染色分析细胞凋亡程度，其结果与PI-DNA染色所得结果一致，对照组仅有少量细胞死亡，低剂量组凋亡细胞较对照组为多（Annexin V-FITC单阳性细胞），高剂量组以坏死细胞为多（Annexin V-FITC/PI双阳性）。 结论： HaCaT细胞经紫外照射后，线粒体去极化作用增强，同时线粒体质量降低，这些变化与细胞凋亡相关。     

Articular cartilage repair in rabbits by using suspensions of allogenic chondrocytes in alginate

The feasibility of allogenic implants of chondrocytes in alginate gels was tested for the reconstruction in vivo of artificially full-thickness-damaged articular rabbit cartilage. The suspensions of chondrocytes in alginate were gelled by the addition of calcium chloride solution directly into the defects giving in situ a construct perfectly inserted and adherent to the subchondral bone and to the walls of intact cartilage. The tissue repair was controlled at 1, 2, 4 and 6 months after the implant by NMR microscopy, synchrotron radiation induced X-ray emission to map the sulfur of glycosaminoglycans and by histochemistry. Practically a complete repair of the defect was observed 4-6 months from the implant of the chondrocytes with the recovery of a normal tissue structure. Controls in which Ca-alginate alone was implanted developed only a fibrous cartilage.     

流式细胞术检测细胞凋亡比较研究

从三方面探讨检测细胞凋亡流式细胞术的方法.选用大鼠皮质神经元细胞,同时使用碘化丙锭(PI)An-nexin V/PI.JC-1法检测细胞凋亡率.结果显示三种方法的凋亡率分别是:2.60%,6.52%和18.56%,两两之间有显著性差异(P＜0.01).JC-1法最敏感,AV/PI次之,PI单染法不适合检测早期细胞凋亡.     

Role of apoptosis inhibition in various chondrocyte culture systems

Apoptosis may limit the utility of cell-based therapies for articular cartilage disorders. We tested the hypothesis that chondrocyte apoptosis can be reduced by optimizing the conditions employed to expand chondrocyte numbers in culture. Chondrocyte apoptosis was examined in monolayer and suspension culture, in the presence of fetal bovine serum (FBS) or autologous serum, and for culture periods of 2 or 4 days. The effect of these variables was assessed by measuring cell viability, Annexin V labeling and mitochondrial membrane potential. After 2 days of culture, the greatest increase in viable cell number (3.7-fold) occurred in monolayer cultures with autologous serum. After 4 days of culture, the greatest increase in cell number (9.0-fold) occurred in monolayer cultures supplemented with FBS. By Annexin V staining, the proportion of cells undergoing apoptosis after 2 days was not affected by the type of serum used or by culture in monolayer versus suspension. After 4 days of culture, the proportion of apoptotic cells was significantly reduced (35% to 13%, p<0.02) in suspension cultures with autologous serum. Apoptosis assessed by loss of mitochondrial membrane potential was decreased in the presence of autologous serum. These data suggest that suspension culture with autologous serum is useful in simultaneously maintaining cell proliferation and minimizing apoptosis in cultured human articular chondrocytes.     

Tissue engineering of articular cartilage using an allograft of cultured chondrocytes in a membrane-sealed atelocollagen honeycomb-shaped scaffold (ACHMS scaffold)

The aim of this study was to investigate with tissue engineering procedures the possibility of using atelocollagen honeycomb-shaped scaffolds sealed with a membrane (ACHMS scaffold) for the culturing of chondrocytes to repair articular cartilage defects. Chondrocytes from the articular cartilage of Japanese white rabbits were cultured in ACHMS scaffolds to allow a high-density, three-dimensional culturing for up to 21 days. Although the DNA content in the scaffold increased at a lower rate than monolayer culturing, scanning electron microscopy data showed that the scaffold was filled with grown chondrocytes and their produced extracellular matrix after 21 days. In addition, glycosaminoglycan (GAG) accumulation in the scaffold culture was at a higher level than the monolayer culture. Cultured cartilage in vitro for 14 days showed enough elasticity and stiffness to be handled in vivo. An articular cartilage defect was initiated in the patellar groove of the femur of rabbits and was subsequently filled with the chondrocyte-cultured ACHMS scaffold, ACHMS scaffold alone, or non-filled (control). Three months after the operations, histological analysis showed that only defects inserted with chondrocytes being cultured in ACHMS scaffolds were filled with reparative hyaline cartilage, and thereby highly expressing type II collagen. These results indicate that implantation of allogenic chondrocytes cultured in ACHMS scaffolds may be effective in repairing articular cartilage defects.     

Ⅱ型胶原水凝胶-细胞复合物在软骨损伤中的应用

BACKGROUND: As the main component of articular cartilage, type II collagen can induce bone marrow mesenchymal stem cells to differentiate into the cartilage. However, there is no uniform standard for the preparation of type II collagen hydrogel and its usage in the repair of sports-induced cartilage injury. OBJECTIVE:To investigate the effect of type II collagen hydrogel-cell complexes in the repair of cartilage injury. METHODS: After modeling, 30 New Zealand rabbits with cartilage injury were randomized into two groups (n=15 per group): type II collagen hydrogel-bone marrow mesenchymal stem cell complexes were implanted into the injured site of rabbits in experimental group, while only type II collagen hydrogel implanted in control group. Histomorphology observation was performed by hematoxylin-eosin and toluidine blue staining after 4 and 8 weeks after implantation. RESULTS AND CONCLUSION: In the experimental group, there were inflammatory cells infiltrated at the injured site, most of which were macrophages and only a small amount of which were neutrophils under hematoxylin-eosin staining, at 4 weeks after implantation, while toluidine blue staining showed no positive. At 8 weeks after implantation, a large amount of chondrocytes proliferated at the injured site that was repaired by chondroblasts and myotubes as well as new vessels under hematoxylin-eosin staining, and toluidine blue staining showed the injured tissues were similar to normal tissues. In the control group, at 4 weeks after implantation, obvious interstitial edema existed, whereas skeletal muscle cells disappeared around the injured site, and a lot of inflammatory cells infiltrated. Several chondroblasts formed at 8 weeks, accompanied by increased fibrous tissues. Moreover, toluidine blue staining always showed no positive in the control group. To conclude, the type II collagen hydrogel-cell complex has better chondrogenic ability that can be used for cartilage repair.     

骨髓间充质干细胞与同种异体脱钙骨基质组合生长因子诱导向软骨细胞分化

背景：用组织工程学方法高质量修复关节软骨缺损并达到很好的远期疗效目前尚无定论。鉴于此,课题组提出“同种异体骨髓间充质干细胞关节腔内定向培养组织工程软骨”的实验设技。 目的：同种异体脱钙骨基质组合转化生长因子β1和胰岛素样生长因子Ⅰ诱导骨髓间充质干细胞向软骨分化的能力,同时探索其在关节腔内培养促进向关节软骨定向分化的方法。 方法：分离兔骨髓间充质干细胞并行体外培养,分为两组：实验组DMEM培养液中加入转化生长因子β1和胰岛素样生长因子Ⅰ,对照组中未加入诱导因子。比较两组细胞的增殖情况和成软骨分化情况。制备同种异体脱钙骨基质支架材料,实验组骨髓间充质干细胞负载到同种异体脱钙骨基质中,构建组织工程软骨复合体,取另2只兔的腰背筋膜包裹后缝合固定到30只兔膝关节腔内行腔内培养。分别于植入后4,8,12周各取10只标本进行组织学切片观察及Ⅱ型胶原免疫组织化学观测,并对结果进行分析。 结果与结论：实验组中骨髓间充质干细胞集落形成效率明显高于对照组(u=3.326,P < 0.01)。实验组细胞爬片做Ⅱ型胶原免疫组化检测呈阳性,对照组未见阳性细胞。组织工程复合体在腔内培养12周后,苏木精-伊红染色见大量软骨细胞增生,胞核染色呈蓝色;甲苯胺蓝染色见软骨细胞成串排列,大量软骨陷窝形成,周围大量基质包绕;Ⅱ型胶原免疫组织化学反应见细胞外基质中出现大量棕黄色颗粒,Ⅱ型胶原染色强阳性。提示转化生长因子β1和胰岛素样生长因子Ⅰ可显著促进骨髓间充质干细胞增殖和成软骨分化,骨髓间充质干细胞与同种异体脱钙骨基质结合后可在关节腔内成功培养出组织工程软骨。同种异体脱钙骨基质符合组织工程软骨支架材料的基本要求。     

丝素蛋白/羟基磷灰石材料复合骨髓间充质干细胞构建组织工程化软骨

背景：随着组织工程的兴起,软骨损伤的修复可能性显著地提高,但单一的支架材料均不能符合理想支架,有一定的局限性。 目的：观察骨髓间充质干细胞复合丝素蛋白/羟基磷灰石构建组织工程化软骨的可行性。 方法：体外分离培养骨髓间充质干细胞,并定向诱导成软骨细胞,与丝素蛋白/羟基磷灰石复合培养,构建膝关节胫骨平台全层关节软骨缺损。54只大白兔单侧膝关节全层软骨缺损模型后随机抽签法分为3组,复合组植入细胞-丝素蛋白/羟基磷灰石复合物;材料组植入单纯丝素蛋白/羟基磷灰石,对照组不行任何植入。植入后8,12周CT检查及组织学检查观察软骨缺损修复情况。 结果与结论：植入后8周,复合组关节面不平整,关节间隙增大,形成新生类软骨细胞,基质丰富。材料组关节面塌陷,软骨细胞少量增殖。植入后12周,复合组关节面平整,关节间隙如常。大量软骨细胞出现,与周边软骨色泽一样,支架材料完全降解。材料组关节面不平整,软骨细胞不完全充填,支架材料部分降解。对照组未见修复。提示用骨髓间充质干细胞复合丝素蛋白/羟基磷灰石可形成透明软骨修复动物膝关节全层软骨缺损,显示了丝素蛋白/羟基磷灰石材料作为关节软骨组织工程支架材料的良好生物相容性。     

A differential assay of NK-cell-mediated cytotoxicity in K562 cells revealing three sequential membrane impairment steps using three-color flow-cytometry

Annexin V and propidium iodide (PI) staining is a general technique for detecting apoptosis by flow-cytometry (FCM). The release of 2',7'-bis-(2-carboxyethyl)-5- (and-6)-carboxyfluorescein (BCECF), a non-lipophilic membrane-impermeable labeling dye, from the cytoplasm of target cells is an indicator of increased membrane permeability. This study aimed to devise a three-color FCM technique involving the BCECF-release parameter in addition to conventional Annexin V and PI staining for the analysis of target K562 cells undergoing cytotoxic/apoptotic processes mediated by natural killer (NK) cells. The results demonstrated the following step-wise process of membrane impairment: (1) initiation of Annexin V staining accompanied by increasing forward scatter (FSC) before BCECF-release, indicating membrane impairment without permeabilization by necrosis; (2) BCECF-release with decreasing FSC before PI influx; and (3) PI staining with the lowest FSC state. Therefore, the early stage of cytotoxicity/apoptosis conventionally defined by the flow-cytometric criteria of Annexin V staining before PI staining could be sub-divided into two stages before and after BCECF-release. Annexin-V staining in tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis was also initiated without BCECF-release. Although the underlying mechanism of the transition process from stage 1 to stage 2 is still unknown, this FCM technique should be a useful tool for differential assays of target cells regarding the sequential processes of NK-induced cytotoxicity.     

选择性切断膝关节神经支对膝骨性关节炎模型兔关节软骨超微结构的影响

目的观察选择性切断膝关节神经支对兔膝骨性关节炎模型关节软骨超微结构的影响。方法采用Huhh法复制兔膝骨性关节炎模型，通过外科显微镜下选择性切断兔膝关节神经支，对关节软骨等结构进行形态学观察，运用TUNEL法检测软骨细胞的凋亡，并应用透射电镜观察关节软骨超微结构的变化。结果模型组兔膝关节软骨出现退变的表现，软骨细胞过度凋亡，其凋亡指数（31．25±6．83）明显高于正常组（3．16±0．65；P〈0．05）。模型组关节软骨超微结构明显受损，软骨细胞出现核固缩，线粒体肿胀，粗面内质网扩张、脱颗粒；软骨基质内胶原纤维断裂溶解，结构模糊。治疗组兔膝关节软骨退变有明显改善，细胞凋亡指数（15．43±3．72）明显低于模型组（P〈0．05），关节软骨超微结构较模型组有明显改善。结论选择性切断膝关节神经支对膝骨性关节炎模型兔关节软骨细胞凋亡有抑制作用，并能改善关节软骨的超微结构。     

Rabbit articular chondrocytes seeded on collagen-chitosan-GAG scaffold for cartilage tissue engineering in vivo

In this study, we prepared a tri-copolymer porous matrices by natural polymer, collagen (Col), Chitosan (Chi) and Chondroitin (CS). Rabbit articular chondrocytes were isolated from the shoulder articular joints of a rabbit, seeded in Col-Chi-CS scaffold, and implanted subcutaneously in the dorsum of athymic nude mice to tissue engineer articular cartilage in vivo. In vitro studies show that Chondrocytes adhered to the scaffold, where they proliferated and secreted extracellular matrices with time, filling the space within the scaffold. The results of hematoxylin and eosin staining scanning electron microscopy revealed that most of the chondrocytes maintained their typically rounded morphology. After 28 days of culture within Col-Chi-CS scaffold in vitro, the results of histological staining showed forming of cartilage-specific morphological appearance and structural characteristics such as lacunae. Subcutaneous implantation studies in nude mice demonstrated that a homogeneous cartilaginous tissue, which was similar to those of natural cartilage, formed when chondrocytes were seeded in Col-Chi-CS matrix after implant 12 weeks. The tri-copolymer matrix could therefore have potential applications as a three-dimensional scaffold for cartilage tissue engineering.     

超声对软骨细胞凋亡、caspase-8和caspase-3表达的影响

背景：超声治疗能够缓解疼痛,改善膝骨关节炎患者的运动功能,但目前关于超声治疗的文献缺乏一致性。 目的：进一步验证超声治疗的膝骨关节炎有效性。 方法：24 只兔子随机分为3组,正常组不干预;模型组兔行前交叉韧带离断诱导膝骨关节炎,不接受任何治疗;超声组兔建模后接受超声波治疗10 min/次,1次/d,0.3 W/cm2,1 MHz,共治疗10次。采用苏木精-伊红染色进行兔关节软骨组织学观察,运用免疫印迹和 RT-PCR技术检测兔软骨中的caspases3和caspases8 的表达,TUNEL技术检测兔膝骨关节软骨细胞凋亡率。 结果与结论：正常兔软骨组织软骨细胞呈柱状整齐的排列,模型中软骨层变薄,软骨细胞排列无序而少。超声治疗后软骨细胞重新排列,趋于整齐,细胞数增加。模型组为膝骨关节炎模型;与正常组比较,模型组和超声组改良Mankin 评分较高,模型组和超声组软骨细胞凋亡指数更高,模型组高于超声组。与正常组比较,模型组和超声组caspase-3 和caspase-8表达较高,超声治疗后两项指标表达下降。结果表明,超声可以改善软骨组织结构、降低caspase-3、caspase -8的表达,降低软骨细胞凋亡。提示超声治疗膝骨关节炎是有效的。     

Lectin-binding in normal and fibrillated articular cartilage of human patellae

Summary Fluorescein-isothiocyanate (FITC) labeled lectins were used to study the distribution of specific binding-sites in histological sections of normal and fibrillated articular cartilage of human patellae.It has been shown that normal articular cartilage reveals lectin binding-sites for Concanavalin A (Con A) and wheat germ agglutinin (WGA), but not for soybean agglutinin (SBA), peanut agglutinin (PNA) and Ulex europaeus agglutinin (UEA).In fibrillated cartilage the distribution pattern of Con A and WGA is completely changed. SBA, PNA and UEA show a distinct staining pattern in particular in the fibrillated areas of degenerated cartilage. Lectin-staining of the extracellular matrix and the chondrocytes in both normal and fibrillated cartilage did not show any correlation with material that was either PAS- or Alcian blue-positive. In comparison with the conventional PAS- and Alcian blue reaction lectin-staining proved to be superior.Visualization of intra- and extracellular glycoconjugate-changes in normal and fibrillated cartilage in areas with no PAS and/or Alcian blue staining indicates that all layers of the cartilage are involved in the pathological process.It is evident that lectins can demonstrate minute differences between normal and arthrotic cartilage and we therefore conclude that lectins are sensitive and specific tools for the study of degenerative joint diseases.     

羟基乙酸负载软骨细胞组织工程软骨修复喉软骨缺损

BACKGROUND: A three-dimensional biodegradable scaffold is important for tissue-engineered cartilage construction, and it that can provide conditions for cell attachment and proliferation. OBJECTIVE: To observe the treatment outcomes of glycolic acid loaded with chondrocytes in laryngeal cartilage repair. METHODS: Sixty New Zealand white rabbits were enrolled and randomly divided into control and experimental groups. Laryngeal cartilage defect models were established in each group, followed by implanted with glycolic acid loaded with chondrocytes and glycolic acid, respectively. Gross and histological observations were conducted at 4 and 8 weeks after implantation. RESULTS AND CONCLUSION: Gross observation showed that at 4 weeks after implantation, a deep red wound with an obvious boundary was seen in the control group; the dark red and smooth defect parallel to the surrounding tissue was found in the experimental group. Toluidine blue staining revealed that at 8 weeks after implantation, the laryngeal defect site showed no obvious inflammation and cartilage collapse, with numerous newly-formed chondrocytes in the experimental group; in contrast, mild inflammation and cartilage collapse were found in the defect region of the control group, and few newly-formed chondrocytes appeared. The positive areas of glycosaminoglycan and type II collagen in the experimental group were significantly larger than those in the control group at 4 and 8 weeks after implantation (P < 0.05). These results indicate that glycolic acid loaded with chondrocytes contributes to the repair of laryngeal cartilage defects.