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1.
兔关节软骨细胞的分离、培养和形态学特征 总被引:9,自引:2,他引:7
[目的]探讨兔关节软骨细胞的分离、培养方法,观察单层高浓度培养时细胞表型表达情况.[方法]无菌条件下,从 2周龄新西兰白兔的颞颌关节及四肢关节髁突面削取软骨片,采用机械-酶消化法分离软骨细胞,经台盼蓝拒染计数,将细胞按 1× 106个 /孔接种于 6孔培养板,传代培养,描绘生长曲线.利用相差显微镜及透射电镜观察细胞形态.应用甲苯胺蓝及Ⅱ型胶原免疫组化对细胞进行鉴定.[结果]每克软骨能获取 1 5× 106个软骨细胞,活性率为 95%.培养 2~ 3 d,细胞贴壁、变形,呈多角形; 8 d左右,细胞融合成层.透射电镜观察显示细胞核圆形,有丰富的粗面内质网、高尔基体及分泌的基质成分.甲苯胺蓝及Ⅱ型胶原染色阳性.细胞传至 5代后,出现"成纤维细胞样".[结论]本研究建立了简单易行的软骨细胞分离、培养方法;初代、第 2代细胞生长良好,适合于实验研究;软骨细胞 5代培养后,细胞表型发生改变. 相似文献
2.
G. J. Breur M. D. Lapierre K. Kazmierczak K. M. Stechuchak G. P. McCabe 《Calcified tissue international》1997,61(5):418-425
In this study, we tested the hypotheses that (a) both the domain volume (volume of the cell and the matrix it has formed)
and matrix volume of juxtametaphyseal hypertrophic chondrocytes in the growth plate is tightly controlled, and that (b) the
domain volume of juxtametaphyseal hypertrophic chondrocytes is a strong determinant of the rate of bone length growth. We
analyzed the rate of bone length growth (oxytetracycline labeling techniques) and nine stereologic and kinetic parameters
related to the juxtametaphyseal chondrocytic domain in the proximal and distal radial and tibial growth plates of 21- and
35-day-old rats. The domain volume increased with increasing growth rates, independent of the location of the growth plate
and the age of the animal. Within age groups, the matrix volume per cell increased with increasing growth rates, but an identical
growth plate had the same matrix volume per cell in 21- and 35-day-old rats. The most suitable regression model (R
2= 0.992) to describe the rate of bone length growth included the mean volume of juxtametaphyseal hypertrophic chondrocytes
and the mean rate of cell loss/cell proliferation. This relationship was independent of the location of the growth plate and
the age of the animal. The data suggest that the domain volume of juxtametaphyseal hypertrophic chondrocytes, as well as the
matrix volume produced per cell, may be tightly regulated. In addition, the volume of juxtametaphyseal hypertrophic chondrocytes
and the rate of cell loss/rate of cell proliferation may play the most important role in the determination of the rate of
bone length growth.
Received: 2 December 1996 / Accepted: 24 March 1997 相似文献
3.
人脂肪干细胞结合微载体在生物反应器中向软骨细胞分化 总被引:3,自引:0,他引:3
[目的]探索在旋转生物反应器内,应用微载体技术快速扩增并向软骨分化人脂肪干细胞。[方法]将人脂肪干细胞结合Cytodex3微载体在旋转的生物反应器(RCSS)内进行动态培养,应用倒置显微镜和扫描电镜对微载体表面的脂肪干细胞进行动态观察,并对收获的脂肪干细胞进行Safran in-O、tolu id ine b lue染色等组织化学染色及Ⅱ型胶原的免疫化学染色分析。[结果]脂肪干细胞于24 h内贴附于Cytodex3微载体表面,细胞形态为短梭形,随时间的延长,贴附于微载体的细胞逐渐增多,到培养后期,细胞密度可达最初接种的19倍左右,在微载体上收获的细胞进行番红花O、阿利新蓝染色呈阳性,Ⅱ型胶原染色阳性,均强于对照组。[结论]利用微载体细胞培养技术可简便快速地在体外扩增脂肪干细胞,并成功实现向软骨细胞分化。 相似文献
4.
R. D’Anchise N. Manta E. Prospero C. Bevilacqua A. Gigante 《Journal of orthopaedics and traumatology》2005,6(1):36-43
Abstract
From our overall experience in 56 patients, we here report the treatment with matrix-induced autologous chondrocyte implantation (MACI) of 35 patients suffering from knee cartilage defects measuring about 4 cm2, and followed for a minimum of 6 months. A total of 36 knees were treated (1 patient on both knees) and clinically observed for 22 months (in some cases for over 39 months), in accordance with a standardised protocol. Subjective parameters (pain, well-being, functional state, symptoms during specific activity) and objective outcomes (IKDC score and Lysholm and Tegner scores) were recorded. One or 2 years after implantation, some biopsies of the regenerated cartilage were histologically evaluated. The subjective parameters (VAS pain score, 2.80±1.49, p<0.0001; change vs. basal score, 2.72) promptly normalized after 1 month, as did the objective ones (IKDC score after 6 months, 1.53±0.59, p<0.0001; change vs. basal score, 1.78). Similar results were observed after the treatment of a femoropatellar kissing lesion. The three cartilage biopsies that were analysed from different patients showed a tissue positivity to immunohistochemical markers of hyaline cartilage. The conclusions of this preliminary analysis are that the clinical outcome and histological evaluation suggest that MACI is able to relieve pain and restore the functionality of the knee, and that the treatment appears capable of regenerating hyaline cartilage. 相似文献
5.
《The Knee》2022
BackgroundPatellofemoral joint cartilage defects are difficult to treat due to their unique thickness and topography.PurposeTo report the postoperative outcomes of patients age 21 and younger treated with particulated juvenile allograft cartilage (PJAC) for full-thickness cartilaginous defects of the patellofemoral joint. The primary aim was to report surgical outcomes and complication rates, as well as return to sport activity. A secondary aim was to provide objective scores of defect restoration by magnetic resonance imaging (MRI) assessment.MethodsA retrospective review of all PJAC cases conducted between 2012 and 2019 at a single tertiary care urban musculoskeletal institution was conducted. Patients 21 years old or younger with minimum clinical follow up of 1 year and postoperative MRI at a minimum of 6 months were included. Cartilage restoration by MRI was independently assessed using the International Cartilage Repair Society’s (ICRS) standardized system.ResultsThirty four patients, 36 knees, were included, with mean age 16.1 ± 3.1 years old. Return to sport rate among patients who participated in a sport preoperatively was 100%. On independent MRI assessment, two thirds of defects achieved an overall grade of normal or nearly normal, while 28 patients (78%) had majority defect fill. Primary graft failure occurred in two cases and one patient experienced a surgical complication.ConclusionRestoration of patellofemoral chondral defects in young patients with particulated juvenile allograft results in satisfactory short-term outcomes and postoperative MRI appearance, along with high rates of return to sport and low rate of complications and graft failure.What is known about the subject: Patellofemoral joint cartilage defects are difficult to treat due to their unique thickness and topography. Several cartilage restoration techniques are available, but these rarely achieve the same mechanical properties as native hyaline cartilage. PJAC is a cell-based technique that has demonstrated promise since its introduction in 2007.What this study adds to existing knowledge: This series of patients adds the largest single cohort of pediatric and adolescent patients who receive PJAC for defects of the patellofemoral joint. Surgeons treating patients in this age group should be aware of every technique, and their respective outcomes. 相似文献
6.
Inoue H Hiraki Y Nawa T Ishizeki K 《Anatomical science international / Japanese Association of Anatomists》2002,77(4):237-246
In order to analyze the phenotypic conversion of chondrocytes, mandibular condyles of mice and rabbits were cultured under
cell and organ culture systems, and then examined by a combination of morphological and biochemical procedures. In organ culture,
mandibular condylar cartilage (MCC) obtained from newborn mice began to mineralize from the central zone and then progressively
widened towards the peripheral zone. Electron microscopic observations showed that with the increasing duration of the organ
culture, chondrocytes at the central zone converted into spindle-shaped osteoblastic cells accompanying the formation of the
bone type of thick-banded collagen fibrils. To obtain a better understanding of the chondrocytic conversion, immunolocalizations
for type I and type X collagens and osteocalcin (OC) were examined in mouse MCC cells in cell culture. Type X collagen and
OC were expressed almost simultaneously at the late stage of culture, and type I collagen was detected along the calcified
nodues after the production of these proteins. Northern blot analysis in cell cultures of rabbit MCC indicated that type II
collagen and alkaline phosphatase (ALPase) messenger ribonucleic acids (mRNAs) were highly expressed at day 7, but subsequently
decreased. In contrast, mRNA for type I collagen was expressed at a low level on day 7 and peaked on day 12. The present results
suggest that, morphologically and biochemically, cellular modification in MCC cells under culture conditions occurs at a cellular
morphological level and also at marker-gene-expression level. 相似文献
7.
Andreas Ratzka Ina Kalus Markus Moser Thomas Dierks Stefan Mundlos Andrea Vortkamp 《Developmental dynamics》2008,237(2):339-353
Modification of the sulfation pattern of heparan sulfate (HS) during organ development is thought to regulate binding and signal transduction of several growth factors. The secreted sulfatases, Sulf1 and Sulf2, desulfate HS on 6-O-positions extracellularly. We show that both sulfatases are expressed in overlapping patterns during embryonic skeletal development. Analysis of compound mutants of Sulf1 and Sulf2 derived from gene trap insertions and targeted null alleles revealed subtle but distinct skeletal malformations including reduced bone length, premature vertebrae ossification and fusions of sternebrae and tail vertebrae. Molecular analysis of endochondral ossification points to a function of Sulf1 and Sulf2 in delaying the differentiation of endochondral bones. Penetrance and severity of the phenotype increased with reduced numbers of functional alleles indicating redundant functions of both sulfatases. The mild skeletal phenotype of double mutants suggests a role for extracellular modification of 6-O-sulfation in fine-tuning rather than regulating the development of skeletal structures. 相似文献
8.
软骨组织工程中力学因素的影响及应用 总被引:1,自引:0,他引:1
力学因素是软骨组织工程中的重要影响因素之一。近年来的研究表明,力学作用可以刺激细胞因子及激素的分泌,改变三维支架上培养的软骨细胞的新陈代谢,从而促进软骨组织的生长与重建。目前已经有诸多关于体外构建软骨组织的报道,但对于其中的力学因素的影响(包括力学因素对软骨细胞增殖的促进及力学刺激的传导机制等)还没有完全认识。就以上几方面做一综述,并简单介绍生物反应器在软骨组织工程中的应用。 相似文献
9.
Miguel Urioste María Luisa Martínez-Frías Eva Bermejo Nicols Jimnez Dolores Romero Carmen Nieto Amelia Villa 《American journal of medical genetics. Part A》1994,49(1):94-97
We report on a newborn infant with clinical and radiological manifestations of some type of short rib-polydactyly syndrome who died soon after birth. Chromosomal studies on peripheral blood lymphocytes and chondrocytes demonstrated an apparently balanced pericentric inversion of chromosome 4 (present in the mother also). This association may have occurred by chance but, if not, the chromosomal breakpoints could interrupt the gene responsible for short rib-polydactyly syndromes, or else be related to the mechanism of short rib-polydactyly syndromes. © 1994 Wiley-Liss, Inc. 相似文献
10.