Repair of Ear Cartilage Defects with Allogenic Bone Marrow Mesenchymal Stem Cells in Rabbits

The study aims to investigate the feasibility of repairing cartilaginous defects with chondrocytes induced from allogenic bone marrow mesenchymal stem cells (BMMSC) in rabbits’ ear. BMMSCs were isolated and purified from New Zealand rabbits, in vitro amplified, and cultured in chondrocyte induction medium in order to acquire chondrocytes. After 3 weeks of induction, their phenotypes were confirmed as chondrocytes, then they were implanted onto novel polymeric scaffolds made from Poly (dl-lactide-co-glycolide) (PLGA) embedded with chitosan nonwoven cloth. The experimental group was transplanted with tissue engineering cartilaginous grafts composed of chondrogenetic BMMSC/scaffolds; the scaffold group was treated with scaffolds without cells, while in the control group, nothing was implanted. Specimens were taken at 6, 12, and 18 weeks after implantation, and the healing condition was observed by hematoxylin-eosin staining and toluidine blue staining. The right and left ears with cartilage defects of eighteen rabbits were randomly divided into three groups. In the experimental group, after 18 weeks of transplantation, the gross observation indicated that the cartilaginous defects were completely repaired by chondrocytes with smooth surface and similar color with the surrounding tissue. Hematoxylin-eosin staining and toluidine blue staining suggested that the defective area was filled with mature cartilage cells with obvious lacunae but without obvious boundaries with the normal cartilage tissue, and that the new cartilage cells were evenly distributed with homogeneously dyed cytoplasm and smaller in size. The chondrocyte induced from allogenic BMMSC can be used to repair cartilage defects in rabbit’s ear.     

Bioactive Copper-Doped Glass Scaffolds Can Stimulate Endothelial Cells in Co-Culture in Combination with Mesenchymal Stem Cells

Bioactive glass (BG) scaffolds are being investigated for bone tissue engineering applications because of their osteoconductive and angiogenic nature. However, to increase the in vivo performance of the scaffold, including enhancing the angiogenetic growth into the scaffolds, some researchers use different modifications of the scaffold including addition of inorganic ionic components to the basic BG composition. In this study, we investigated the in vitro biocompatibility and bioactivity of Cu²⁺-doped BG derived scaffolds in either BMSC (bone-marrow derived mesenchymal stem cells)-only culture or co-culture of BMSC and human dermal microvascular endothelial cells (HDMEC). In BMSC-only culture, cells were seeded either directly on the scaffolds (3D or direct culture) or were exposed to ionic dissolution products of the BG scaffolds, kept in permeable cell culture inserts (2D or indirect culture). Though we did not observe any direct osteoinduction of BMSCs by alkaline phosphatase (ALP) assay or by PCR, there was increased vascular endothelial growth factor (VEGF) expression, observed by PCR and ELISA assays. Additionally, the scaffolds showed no toxicity to BMSCs and there were healthy live cells found throughout the scaffold. To analyze further the reasons behind the increased VEGF expression and to exploit the benefits of the finding, we used the indirect method with HDMECs in culture plastic and Cu²⁺-doped BG scaffolds with or without BMSCs in cell culture inserts. There was clear observation of increased endothelial markers by both FACS analysis and acetylated LDL (acLDL) uptake assay. Only in presence of Cu²⁺-doped BG scaffolds with BMSCs, a high VEGF secretion was demonstrated by ELISA; and typical tubular structures were observed in culture plastics. We conclude that Cu²⁺-doped BG scaffolds release Cu²⁺, which in turn act on BMSCs to secrete VEGF. This result is of significance for the application of BG scaffolds in bone tissue engineering approaches.     

Polydimethylsiloxane Films Modified with Chitosan/Pectin Multilayers as Scaffolds for Mesenchymal Stem Cells

Solid (smooth) and porous films of polydimethylsiloxane (PDMS) have been obtained; the effect of their structure on the adhesion of mesenchymal stem cells (MSCs) on their surface was found. It is shown that modification of these films with a (chitosan/pectin)₄ multilayer increased the efficiency of viable cell adhesion. A (3-aminopropyl)triethoxysilane–glutaraldehyde system was used to enhance the binding of the polysaccharide layer to the hydrophobic surface of PDMS. It was found that MSCs formed a monolayer culture of the fibroblast-like cells with high viability on porous PDMS modified with (chitosan/pectin)₄.     

自组装多肽纳米纤维支架诱导骨髓间充质干细胞定向分化

组织工程是现代修复重建医学领域的新思路,生物支架和种子细胞是组织工程两大关键要素。自组装多肽纳米纤维支架(SAPNS)是两亲性多肽(PAs)分子在一定条件下自组装成的一类具有三维网状结构的新型生物支架,其结构、生物功能、机械力学等特性类似天然细胞外基质(ECM),其内部经功能化修饰的抗原表位以高浓度呈递在纳米纤维表面并高效选择性地调控种子细胞生物学行为。种子细胞是组织成功再生的必需条件,骨髓间充质干细胞(BMSCs)因其良好的自我更新和多向分化潜能成为了组织工程最佳候选细胞。体外实验表明经特异功能化修饰的SAPNS在有/无辅助因子条件下可促进BMSCs黏附、增殖、迁移和定向分化,动物模型体内实验发现SAPNS结合BMSCs构建的组织工程移植物可修复缺损部位的组织结构和功能,故其在修复重建医学中有良好的应用前景。对SAPNS、自组装、BMSCs、SAPNS诱导BMSCs定向分化等方面进行了综述。     

Implantation of Ferumoxides Labeled Human Mesenchymal Stem Cells in Cartilage Defects

The field of tissue engineering integrates the principles of engineering, cell biology and medicine towards the regeneration of specific cells and functional tissue. Matrix associated stem cell implants (MASI) aim to regenerate cartilage defects due to arthritic or traumatic joint injuries. Adult mesenchymal stem cells (MSCs) have the ability to differentiate into cells of the chondrogenic lineage and have shown promising results for cell-based articular cartilage repair technologies. Autologous MSCs can be isolated from a variety of tissues, can be expanded in cell cultures without losing their differentiation potential, and have demonstrated chondrogenic differentiation in vitro and in vivo^{1, 2}.In order to provide local retention and viability of transplanted MSCs in cartilage defects, a scaffold is needed, which also supports subsequent differentiation and proliferation. The architecture of the scaffold guides tissue formation and permits the extracellular matrix, produced by the stem cells, to expand. Previous investigations have shown that a 2% agarose scaffold may support the development of stable hyaline cartilage and does not induce immune responses³.Long term retention of transplanted stem cells in MASI is critical for cartilage regeneration. Labeling of MSCs with iron oxide nanoparticles allows for long-term in vivo tracking with non-invasive MR imaging techniques⁴.This presentation will demonstrate techniques for labeling MSCs with iron oxide nanoparticles, the generation of cell-agarose constructs and implantation of these constructs into cartilage defects. The labeled constructs can be tracked non-invasively with MR-Imaging.Open in a separate windowClick here to view.^{(27M, flv)}     

比格犬会厌黏膜来源干细胞的分离培养与生物学特性鉴定

目的:探讨建立喉部黏膜间充质干细胞的分离培养方法,并对其生物学特性进行鉴定,为进一步研究其在喉部瘢痕中形成的作用及喉部组织工程提供参考.方法:以比格犬喉部会厌背侧(舌面)黏膜为研究对象,采用消化培养的方法分离具有间充质干细胞样细胞.选取第3代细胞对其进行生物学特性鉴定,首先利用MTT法检测其增殖活性及克隆形成情况,然后通过流式细胞术检测细胞表面分子标记物CD29及CD34的表达情况,最后应用第3代细胞对其进行成脂肪细胞和成骨细胞分化培养,观察其分化能力.结果:分离培养细胞形态较为一致,绝大多数呈梭形,排列不规则.MTT增殖活性实验及克隆形成试验结果显示,所分离的细胞具有良好的增殖活性和克隆形成率;流式细胞术结果显示,该细胞表达CD29间充质干细胞细胞表面标记物,低表达造血干细胞细胞表面标记物CD34;同时,该细胞诱导分化成脂肪细胞和成骨细胞实验表明,其具有多向分化潜能.结论:从比格犬会厌背侧黏膜分离的细胞具有间充质干细胞样特性,为进一步研究喉部瘢痕形成机制及喉部组织工程提供了技术基础.     

Effect of Pulsed Electromagnetic Fields on Human Mesenchymal Stem Cells Using 3D Magnetic Scaffolds

Alternative bone regeneration strategies that do not rely on harvested tissue or exogenous growth factors are needed. One of the major challenges in tissue reconstruction is recreating the bone tissue microenvironment using the appropriate combination of cells, scaffold, and stimulation to direct differentiation. This study presents a bone regeneration formulation that involves the use of human adipose-derived mesenchymal stem cells (hASCs) and a three-dimensional (3D) hydrogel scaffold based on self-assembled RADA16 peptides containing superparamagnetic iron oxide nanoparticles (NPs). Although superparamagnetic NPs could be used as stimulus to manipulate the cell proliferation and differentiation, in this paper their use is explored for assisting osteogenic differentiation of hASCs in conjunction with direct stimulation by extremely low-frequency pulsed electromagnetic fields (pEMFs). Cellular morphology, proliferation, and viability, as well as alkaline phosphatase activity, calcium deposition, and osteogenic capacity were monitored for cells cultured up to 21 days in the 3D construct. The results show that the pEMFs and NPs do not have any negative effect on cell viability, but instead distinctly induced early differentiation of hASCs to an osteoblastic phenotype, when compared with cells without biophysical stimulation. This effect is attributed to synergy between the pEMFs and NPs, which may have stimulated mechanotransduction pathways, which, in turn activated biochemical signals between cells to differentiate or proliferate. This approach may offer a safe and effective option for the treatment of non-union bone fractures. Bioelectromagnetics. © 2020 The Authors. Bioelectromagnetics published by Wiley Periodicals, Inc.     

间充质干细胞过滤分离器制备人羊膜间充质干细胞的研究

自然存在的间充质干细胞数量少,限制了其研究应用。依靠自主发明的间充质干细胞过滤分离器,分离制备了人羊膜间充质干细胞,并对制备的干细胞进行了三维培养扩增。结果表明,制备的干细胞形态长势良好,并能诱导分化为类胰岛样组织。与常规方法相比,干细胞收获率提高了8倍以上,且细胞活性状态良好。间充质干细胞过滤分离器可以批量制备高质量的各种间充质干细胞,有利于高效率地建设各种间充质干细胞库,以促进间充质干细胞的研究应用。     

间充质干细胞与肿瘤转移

间充质干细胞是一类能够自我更新、具有多向分化潜能的成体干细胞。近年来,有证据认为间充质干细胞是肿瘤组织中基质细胞的祖先,因此间充质干细胞微环境与肿瘤转移的关系逐渐成为研究热点,但间充质干细胞对肿瘤转移是促进还是抑制,目前的研究并不一致。我们简要综述了间充质干细胞参与肿瘤转移的研究进展。     

人滑膜间充质干细胞与人脐带间充质干细胞的生物学性状比较

该文旨在比较人滑膜间充质干细胞(human synovial mesenchymal stem cells,hSMSCs)与人脐带间充质干细胞(human umbilical cord mesenchymal stem cells,hUC-MSCs)的生物学性状.流式细胞仪鉴定hSMSCs和hUC-MSCs.比较两种间...     

自体骨髓间充质干细胞移植治疗股骨头无菌性坏死的临床观察

目的:观察自体骨髓间充质干细胞移植治疗股骨头无菌性坏死的临床效果及安全性.方法:对2012年9月至2013年1月期间在我院骨科住院治疗的55例患者随机分成两组,对照组接受常规治疗,治疗组接受自体骨髓间充质干细胞移植治疗治疗.结果:治疗组的临床疗效优于对照组,与对照组相比差异有统计学意义(P＜0.01);治疗组治疗后的DSA检查结果与对照相比,差异有统计学意义(P＜0.05);两组不良反应相互比较,无统计学意义(P＞0.05).结论:自体骨髓间充质干细胞移植治疗股骨头无菌性坏死效果显著,优于常规治疗.     

骨髓间充质干细胞的研究进展

骨髓间充质干细胞是存在于骨髓中的具有高度自我更新能力和多向分化潜能的干细胞群体 ,具有支持造血、多向分化潜能以及在细胞和基因工程中具有潜在应用前景等特点 ,将在医学上具有重要的临床应用价值。     

The Methods and Mechanisms to Differentiate Endothelial-Like Cells and Smooth Muscle Cells from Mesenchymal Stem Cells for Vascularization in Vaginal Reconstruction

Endothelial cells and smooth muscle cells (SMCs) are important aspects of vascularization in vaginal reconstruction. Research has confirmed that mesenchymal stem cells could differentiate into endothelial-like cells and SMCs. But the methods were more complicated and the mechanism was unknown. In the current study, we induced the bone mesenchymal stem cells (BMSCs) to differentiate into endothelial-like cells and SMCs in vitro by differentiation medium and investigated the effect of Wnt/β-catenin signaling on the differentiation process of BMSCs. Results showed that the hypoxic environment combined with VEGF and bFGF could induce increased expression of endothelial-like cells markers VEGFR1, VEGFR2, and vWF. The SMCs derived from BMSCs induced by TGF-β1 and PDGF-AB significantly expressed SMC markers SMMHC11 and α-SMA. The data also showed that activation of Wnt/β-catenin signaling could promote the differentiation of BMSCs into endothelial-like cells and SMCs. Thus, we established endothelial-like cells and SMCs in vitro by more simple methods, presented the important role of hypoxic environment on the differentiation of BMSCs into endothelial-like cells, and confirmed that the Wnt/β-catenin signaling pathway has a positive impact on the differentiation of BMSCs into endothelial-like cells and SMCs. This is important for vascular reconstruction.     

脐带间充质干细胞与再生障碍性贫血

再生障碍性贫血(aplastic anemia,AA)是由于物理、化学、生物或不明因素作用使骨髓造血干细胞和骨髓微环境严重受损,造成骨髓造血功能降低或衰竭,以全血细胞减少为主要表现的一组综合征。间充质干细胞(MSC)是属于中胚层的一类多能干细胞,主要存在于结缔组织和器官间质中。不仅具有多向分化潜能,还有多种免疫调节作用。许多研究表明MSCs抑制同种异体效应T淋巴细胞增殖,还能下调T淋巴细胞表面的活化分子CD25、CD38、CD69的表达。MSCs对DCs的分化、成熟和活化具有抑制作用,改变DCs的细胞因子分泌,使成熟的DCl分泌TNF-a减少,DC2分泌IL-10增加,从而抑制T淋巴细胞增殖。MSCs能够抑制IL-2和IL-15介导的NK细胞增殖,使IL-2刺激NK细胞分泌的IFN-y减少。通过这些机制来干预再生障碍性贫血,同时研究发现MSCs免疫原性较低。尤其脐带MSC,因为其独特优势,目前已经成为干细胞干预治疗AA的研究热点。     

间充质干细胞与肿瘤的关系

最近的研究表明问充质干细胞(mesenchymal stem cells,MSCs)与多种肿瘤的发生发展有密切关系.MSCs对多种肿瘤具有趋向性,外源性(局部混合注射或静脉注射)MSCs可参与肿瘤间质的形成,同时MSCs的免疫抑制作用可以促进肿瘤在体内的生长.通过细胞因子介导或直接的细胞接触,MSCs与多种肿瘤细胞之间存在相互作用.MSCs可以抑制肿瘤细胞的的凋亡,促进肿瘤细胞的增殖及肿瘤的转移.由于MSCs易于分离、体外扩增及进行基因修饰,因此可以利用MSCs对肿瘤的趋向性,使MSCs携带抗肿瘤基因来实现对肿瘤的靶向治疗.     

Human Mesenchymal Stem Cells Signals Regulate Neural Stem Cell Fate

Neural stem cells (NSCs) differentiate into neurons, astrocytes and oligodendrocytes depending on their location within the central nervous system (CNS). The cellular and molecular cues mediating end-stage cell fate choices are not completely understood. The retention of multipotent NSCs in the adult CNS raises the possibility that selective recruitment of their progeny to specific lineages may facilitate repair in a spectrum of neuropathological conditions. Previous studies suggest that adult human bone marrow derived mesenchymal stem cells (hMSCs) improve functional outcome after a wide range of CNS insults, probably through their trophic influence. In the context of such trophic activity, here we demonstrate that hMSCs in culture provide humoral signals that selectively promote the genesis of neurons and oligodendrocytes from NSCs. Cell–cell contacts were less effective and the proportion of hMSCs that could be induced to express neural characteristics was very small. We propose that the selective promotion of neuronal and oligodendroglial fates in neural stem cell progeny is responsible for the ability of MSCs to enhance recovery after a wide range of CNS injuries. Special issue dedicated to Anthony Campagnoni.     

Human Umbilical Mesenchymal Stem Cells-Seeded Bladder Acellular Matrix Grafts for Reconstruction of Bladder Defects in a Canine Model

Background

The goal of this study was to explore the feasibility of utilizing human umbilical mesenchymal stem cells (HUMSCs)-seeded Bladder acellular matrix graft (BAMG) for bladder reconstruction in a canine model.

Methodology/Principal Findings

HUMSCs were isolated from newborn umbilical cords and identified by flow cytometry. Partial cystectomy was performed in the experimental and control group. Bladder defects were repaired with HUMSCs-BAMG in the experimental group and repaired with unseeded-BAMG in control group. The implanted grafts were harvested after surgery. H&E and immunohistochemistry staining were performed to evaluate the regeneration of the bladder defect. Primary cultured HUMSCs displayed typical fibroblast morphology with spindle-shaped. Flow cytometry indicated that these cells were positive for CD105 (97.3%) and CD44 (99%), but negative for CD34 (2.8%), CD31 (2.1%), and CD45 (1.7%). Immunohistochemistry staining showed that a multilayered urothelium and well-developed smooth muscle were observed at 12 weeks in experiment group. In contrast, multilayered urothelial tissues were also observed at 12 weeks in group B, but well-developed smooth muscle bundles were observed.

Conclusions/Significance

Our preliminary results demonstrate that UMSC-seeded BAMGs are superior to unseeded BAMGs to promote the regeneration of bladder defects. Our findings indicated that HUMSCs may be a potential cell source for bladder tissue engineering.