生长因子与牙周组织工程

生长因子的开发和合理运用是促进牙周组织工程种子细胞再生潜力发挥的重要因素之一。本文重点综述各类生长因子在牙周再生中的作用特点及其注意事项。     

生长因子在组织工程中的应用

生长因子具有促进细胞增殖 ,组织或血管的修复和再生的作用 ,是组织工程的三个主要研究方面之一。本文对目前组织工程领域研究和应用的一些重要生长因子的主要作用以及近期的实验进展进行了综述 ,并指出了当前生长因子临床应用所面临的问题以及今后的研究方向     

转化生长因子及其受体和受体相互作用蛋白在肺癌组织中的检测

我们分别采用免疫组化和Ｎｏｒｔｈｅｒｎ杂交方法，观察了肺癌细胞转化生长因子β（ＴＧＦβ）信息传递通路中主要信号分子ＴＧＦβ１、ＴＧＦβ２、ＴβＲＩ、ＴβＲⅡ以及受体相互作用蛋白１（ＴＧＦβｒｅｃｅｐｔｏｒｉｎｔｅｒａｃｔｉｎｇｐｒｏｔｅｉｎ１，ＴＲＩＰ１）在肺癌、癌旁和正常肺组织中的表达状况，以探讨ＴＧＦβ与肺癌发生发展的关系。一、材料与方法１－一般资料：６５例标本均取自本院１９９６年９月～１９９８年４月手术切除病理确诊的肺癌患者。男５５例，女１０例；年龄２６～８１岁，平均５８－４岁；…     

关节软骨组织工程的研究进展

介绍了关节软骨组织工程中种子细胞、支架材料的研究现状以及生长因子在关节软骨组织工程中的应用进展，阐明了随着对细胞行为、支架材料特性、细胞与材料的组合构建研究的深入，组织工程在关节软骨修复方面应用前景十分广阔。     

生长因子在组织工程中的应用

生长因子具有促进细胞增殖，组织或血管的修复和再生的作用，是组织工程的三个主要研究方面之一。本对目前组织工程领域研究和应用的一些重要生长因子的主要作用以及近期的实验进展进行了综述，并指出了当前生长因子临床应用所面临的问题以及今后的研究方向。     

生长因子与牙周组织工程

生长因子的开发和合理运用是促进牙周组织工程种子细胞再生潜力发挥的重要因素之一。本文重点综述各类生长因子在牙周再生中的作用特点及其注意事项。     

生长因子对骨骼肌损伤与修复的作用

BACKGROUND: Growth factors involved in the regulation of cellular processes play an important role in the wound healing and tissue regeneration. OBJECTIVE:To elaborate the role of a variety of cellular processes involving growth factors in the repair of skeletal muscle injury, and to provide the references for the treatment and rehabilitation strategies, and the synthesis of biomaterials with growth factor for the skeletal muscle after injury. METHODS: A computer-based online search was conducted in PubMed, Mendeley, Google Scholar, and CNKI databases from 1995 to November 2015 to screen the relevant literatures using the keywords “skeletal muscle, damage repair, insulin-like growth factor, epidermal growth factor, growth factor”. Data screening, processing, and summary were performed. RESULTS AND CONCLUSION: Fifty-one eligible literatures were included. Exercise training promotes the repair and regeneration of the injured skeletal muscle cells and the recovery of the function by activating satellite cells in the sarcolemma and basement membrane to produce the numerous myoblasts. The repair involves the complex biological process regulated by growth factors. Exogenous growth factors up-regulate the mRNA expression of endogenous growth factors, stimulate the proliferation of the myoblasts, accelerate the fusion between myotubes and muscle fibers, promote the repair of skeletal muscle injury, inhibit the formation of scars, thereby enhancing the healing quality. 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程     

明胶基生物材料在组织工程中的应用

本主要对明胶及其复合材料在组织工程领域的研究进展作了评述，表明明胶基生物材料作为种子细胞和信号分子的载体具有广阔的应用前景。     

血管组织工程相关生长因子的控制释放研究进展

生长因子在细胞的黏附、增殖和组织的再生过程中发挥着重要的作用。将生长因子负载于高分子材料支架上，可以实现对生长因子的控制释放。其释放机制随负载方法的不同而存在着差异。本文总结了共混、凝胶、微球包埋以及化学键合法在血管组织工程中相关生长因子控制释放方面的研究进展，并指出了超细纤维包埋法的应用前景。     

血管内皮细胞生长因子与实体肿瘤

血管内皮细胞生长因子（ＶＥＧＦ）具有选择性促血管内皮细胞生长和增强血管渗透性的作用，在多种实体肿瘤中有高水平合成，并与肿瘤的分级和转移相关，ＶＥＧＦ受体主要表达于血管内皮细胞，通过干预ＶＥＧＦ及其受体抑制肿瘤血管形成是阻遏肿瘤生长和转移的重要策略     

电穿孔转染酸性成纤维细胞生长因子基因对骨骼肌卫星细胞的影响

背景：课题组早期研究表明体外一定剂量酸性成纤维细胞生长因子对骨骼肌卫星细胞增殖有促进作用。 目的：进一步验证电穿孔转染酸性成纤维细胞生长因子基因对骨骼肌卫星细胞生长、增殖及分化的影响。 方法：原代培养、纯化骨骼肌卫星细胞,将带有酸性成纤维细胞生长因子基因的质粒pSectag-GFP-aFGF通过电转染的方法转染大鼠骨骼肌卫星细胞,荧光显微镜观察绿色荧光蛋白的表达情况并计算转染率,以流式细胞仪分析转染后细胞周期,绘制细胞生长曲线,观察转染后肌管形成情况,Western Bloting检测酸性成纤维细胞生长因子基因的表达。 结果与结论：①免疫细胞化学检测：骨骼肌肌动蛋白呈阳性表达。②转染效率：pSectag-aFGF质粒电转染12 h后即可看见散在发绿色荧光的卫星细胞,72-96 h达高峰,阳性表达率约90%。③细胞周期检测：电转染后S期所占的百分比明显多于未转染对照组(P < 0.05)。④细胞生长曲线检测：电转染细胞接种后第3天进入对数生长期,第5天后开始减少。⑤分化能力观察：电转染组肌管较未转染对照组明显减少,老化细胞较少。⑥Western-blot：酸性成纤维细胞生长因子基因在转染骨骼肌卫星细胞中表达。结果表明,通过电穿孔法可以将酸性成纤维细胞生长因子基因转染进骨骼肌卫星细胞并获得高效持久的表达,并有促进骨骼肌卫星细胞增殖及抑制分化为肌管的作用。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;组织工程全文链接：     

Regenerative function of immune system: Modulation of muscle stem cells

Ageing is characterised by progressive deterioration of physiological systems and the loss of skeletal muscle mass is one of the most recognisable, leading to muscle weakness and mobility impairments. This review highlights interactions between the immune system and skeletal muscle stem cells (widely termed satellite cells or myoblasts) to influence satellite cell behaviour during muscle regeneration after injury, and outlines deficits associated with ageing. Resident neutrophils and macrophages in skeletal muscle become activated when muscle fibres are damaged via stimuli (e.g. contusions, strains, avulsions, hyperextensions, ruptures) and release high concentrations of cytokines, chemokines and growth factors into the microenvironment. These localised responses serve to attract additional immune cells which can reach in excess of 1 × 10⁵ immune cell/mm³ of skeletal muscle in order to orchestrate the repair process. T-cells have a delayed response, reaching peak activation roughly 4 days after the initial damage. The cytokines and growth factors released by activated T-cells play a key role in muscle satellite cell proliferation and migration, although the precise mechanisms of these interactions remain unclear. T-cells in older people display limited ability to activate satellite cell proliferation and migration which is likely to contribute to insufficient muscle repair and, consequently, muscle wasting and weakness. If the factors released by T-cells to activate satellite cells can be identified, it may be possible to develop therapeutic agents to enhance muscle regeneration and reduce the impact of muscle wasting during ageing and disease.     

骨骼肌卫星细胞生长因子与运动训练的关系

背景：大运动量训练可以导致骨骼肌组织微细结构的损伤性变化, 而骨骼肌卫星细胞的激活、增殖与分化和肌肉组织损伤的修复有密切关系。 目的：文章从训练导致肌肉组织结构性损伤需要修复的客观实际出发,提出运动后骨骼肌结构的修复与骨骼肌卫星细胞生长因子之间存在某种依赖关系。 方法：由第一作者通过计算机网络检索中国期刊全文数据库(CNKI)和Medline数据库(2000/2010),检索词分别为“骨骼肌卫星细胞,生长因子,运动训练,骨骼肌超微结构”和“Skeletal muscle satellite cells,exercise,growth factor”。 共检索到97篇文章,按纳入和排除标准对文献进行筛选,共纳入23篇文章。从运动后骨骼肌组织修复与骨骼肌卫星细胞生长因子的激活作用机制进行总结,对两者间的联系进行分析。 结果与结论：大强度训练可以导致骨骼肌组织的损伤,而卫星细胞是运动后恢复期骨骼肌修复的关键,其生长因子也与训练方式等因素有关。目前在骨骼肌卫星细胞的生长因子与运动训练之间的联系还缺乏足够的认识与研究。     

生长因子在关节软骨损伤修复中的应用进展

关节是人体重要的运动器官,其组织结构特殊,成熟关节软骨组织没有血供,一旦损伤难以自愈.临床上常用的关节软骨损伤修复手段有微骨裂术、关节软骨移植、关节置换术、软骨组织工程等,但这些方法的修复效果都不理想.生长因子是体内组织分泌的一种具有生物活性的物质,可促进细胞生长、增殖、迁移和分化.软骨发育过程中有许多生长因子参与,如成纤维细胞生长因子(FGF)、骨形态发生蛋白(BMP)、胰岛素样生长因子(IGF)等.研究显示,在关节软骨修复过程中加入外源性生长因子可有效促进关节软骨损伤的修复.对目前应用于关节软骨损伤修复研究中的生长因子进行综述,讨论这些生长因子在关节软骨发育及其在关节软骨修复中的作用,分析生长因子在关节软骨修复应用中存在的问题.     

复合富血小板血浆珊瑚骨修复下颌骨缺损

BACKGROUND: Platelet rich plasma contains various growth factors, such as platelet-derived growth factor, metastatic growth factor, insulin-like growth factor, epidermal growth factor as well as vascular endothelial growth factor. Therefore, it can directly or indirectly promote cell differentiation and proliferation in different stages of bone regeneration.     

Satellite cells express the trophic factor IGF-I in regenerating skeletal muscle

The expression of insulin-like growth factor I (IGF-I, somatomedin C) was studied in regenerating skeletal muscle. Irreversible damage to skeletal muscle cells was induced in the extensor digitorum longus muscle (EDL) of adult rats by ischaemia, preceded by glycogen depletion, and the regeneration process was studied for periods up to 14 days after injury. The IGF-I was demonstrated by indirect immunofluorescence. Immunoreactivity against ribonucleotide reductase (RR) was used as a marker for DNA synthesis, that is, cell proliferation. Increased IGF-I immunoreactivity could be demonstrated within 24h after injury in satellite cells, intramuscular nerves and in blood vessels. The IGF-I immunoreactivity remained virtually unchanged in the contralateral, undamaged EDL. An increasing number of satellite cells, expressing high IGF-I immunoreactivity, could be demonstrated in the injured EDL, and within 72 h myoblasts, expressing high IGF-I and RR immunoreactivity, were formed. Small immature muscle cells, displaying high IGF-I immunoreactivity, were observed 4 days after injury. Increased IGF-I immunoreactivity was still obvious in the regenerated muscle cells 14 days after injury while RR immunoreactivity was seen only in scattered satellite cells. It is concluded that IGF-I may act as a trophic factor during regeneration of skeletal muscle after injury.     

Mechanisms of muscle stem cell expansion with cytokines.

Stem cell expansion and proliferation are important for cell transplantation and stem cell-mediated applications. While we have demonstrated that muscle stem cells can be obtained from adult skeletal muscle tissue, these cells represent only a small percentage of the muscle-derived cells and require in vitro expansion for successful stem cell-mediated therapies. In this study, we have examined the potential of several cytokines to stimulate stem cell growth by combining a non-exponential mathematical model with a unique cell culture system. The growth kinetics of two populations of muscle stem cells were characterized in culture medium supplemented with epidermal growth factor (EGF), fibroblast growth factor-2 (FGF-2), insulin-like growth factor-1 (IGF-1), FLT-3 ligand, hepatocyte growth factor, or stem cell factor (SCF). The division time (DT) and fraction of mitotically active cells were investigated as key parameters to further understand the mechanism of the expansion of the stem cell populations. Our results show that expansion of the freshly isolated, muscle-derived stem cells (MDSC) occurred by recruiting cells into the cell cycle in the presence of EGF, IGF-1, and SCF. However, expansion of the cultured stem cell clone, MC13, is attributed to a reduction of the length of the cell cycle in the presence of FGF-2, EGF, IGF-1, and SCF. Both MDSC and MC13 growth were inhibited in the presence of FLT-3 ligand by increasing the length of the cell cycle. Our results suggest that EGF, IGF-1, FGF-2, and SCF are important cytokines for stimulating the proliferation of MDSC. In addition, this study illustrates that expansion of stem cells occurs through different mechanisms, which consequently demonstrates the importance of monitoring several parameters of cell growth, such as DT and dividing fraction, following stimulation with growth factors.     

Exercise-induced muscle damage and inflammation: fact or fiction?

Physical exercise is necessary for maintaining normal function of skeletal muscle. The mechanisms governing normal muscle function and maintenance are vastly unknown but synergistic function of hormones, neurosignalling, growth factors, cytokines and other factors, is undoubtedly important. Because of the complex interaction among these systems the lack of complete understanding of muscle function is not surprising. The purpose of exercise-induced changes in muscle cell function is to adapt the tissue to a demand of increased physical work capacity. Some of the approaches used to investigate changes in skeletal muscle cell function are exercise and electrical stimulation in animals and human models and isolated animal muscle. From these models, it has been concluded that during physical exercise, in an intensity and duration dependent manner, skeletal muscle is damaged and subsequently inflamed. The purpose of the inflammation would be to repair the exercise-induced damage. Because of the design and methods used in a majority of these studies, concerns must be raised, and the question asked whether the paradigm of exercise-induced muscle inflammation in fact is fiction. In a majority of conducted studies, a non-exercising control group is lacking and because of the invasive nature of the sampling methods used to study inflammation it does not appear impossible that observed inflammatory events in human skeletal muscle after physical exercise are methodological artefacts.     

Fibroblasts influence muscle progenitor differentiation and alignment in contact independent and dependent manners in organized co-culture devices

Myoblasts are precursor muscle cells that lie nascent to mature skeletal muscle. Once muscle is damaged, these cells migrate, fuse, and regenerate the muscle tissue. It is known that skeletal muscle can partially regenerate in vivo after muscle tissue damage. However, this regeneration does not always occur, especially in more severe injuries. Cellular therapy using tissue-engineering approaches has been shown to improve organ repair and function. To exploit potential benefits of using cell therapy as an avenue for skeletal muscle repair, it is important to understand the cellular dynamics underlying skeletal myocyte formation and growth. Cardiac fibroblasts have been shown to have a major influence on cardiomyocyte function, repair, and overall spatial distribution. However, little is known regarding fibroblasts’ role on skeletal myocyte function. In this study, we utilized a reconfigurable co-culture device to understand the contact and paracrine effects of fibroblasts on skeletal myocyte alignment and differentiation using murine myoblast and fibroblast cell lines. We demonstrate that myotube alignment is increased by direct contact with fibroblasts, while myotube differentiation is reduced both in the gap and contact configurations with fibroblasts after 6 days of co-culture. Furthermore, neutralizing antibodies to FGF-2 can block these effects of fibroblasts on myotube differentiation and alignment. Finally, bi-directional signaling is critical to the observed myoblast-fibroblast interactions, since conditioned media could not reproduce the same effects observed in the gap configuration. These findings could have direct implications on cell therapies for repairing skeletal muscle, which have only utilized skeletal myoblasts or stem cell populations alone.