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1.
目的采用倒置显微镜、扫描电镜(scanning electron microscopy,SEM)、荧光显微镜和激光共聚焦显微镜((laser scanning confocal microscopy,LSCM))技术对大鼠颌下腺细胞(rat submandibular gland cells,RSMGs)与丝素-壳聚糖(silk fibroin-chitosan,SFCs)的体外复合培养进行形态学观察。为观测、评估种子细胞在三维支架的内部生长情况提供技术支持。方法取0~8 d龄SD大鼠的颌下腺,对大鼠颌下腺细胞进行原代培养、分离纯化并传代;用抗细胞角蛋白单克隆抗体(CK8)及淀粉酶抗体的免疫细胞化学染色鉴定细胞来源。选取传至第二代的对数生长期的RSMGs作为种子细胞,选取SFCs共混膜(5×5×2)mm作为支架材料构建组织工程化涎腺样结构。将种子细胞与支架材料复合培养并分别于倒置显微镜、SEM、荧光显微镜和LSCM下观察二者复合生长情况。结果倒置显微镜可以直接观察活细胞与支架复合生长情况,方法简单易行。SEM可以较精确的展示细胞支架复合生长的表面超微结构。经过荧光染料的着色,荧光显微镜和LSCM都可以观察到支架上锚定的种子细胞。荧光显微镜可见细胞核的荧光信号均匀的分布在支架孔隙内。LSCM通过层扫描及三维重建技术对较厚的标本获取图像;并可以通过旋转图像,从不同角度观察细胞支架复合物的三维剖面或整体结构,得到更为准确的定位信息。结论四种显微技术均可应用于RSMGs与SFCs体外共培养的形态学观测。LSCM的三维重建技术结合荧光染料标记可以较好地获得RSMGs与SFCs复合生长的情况,有着较广泛的应用价值。  相似文献   

2.
Monolayer formation of SaOS‐2 (human osteoblast‐like cells) was observed on VACNT (vertically aligned multiwalled carbon nanotubes) scaffolds without purification or functionalization. The VACNT were produced by a microwave plasma chemical vapour deposition on titanium surfaces with nickel or iron as catalyst. Cell viability and morphology studies were evaluated by LDH (lactate dehydrogenase) release assay and SEM (scanning electron microscopy), respectively. The non‐toxicity and the flat spreading with monolayer formation of the SaOs‐2 on VACNT scaffolds surface indicate that they can be used for biomedical applications.  相似文献   

3.
Bone tissue engineering offers promising alternatives to repair and restore tissues. Our laboratory has employed poly(lactide-co-glycolide) PLAGA microspheres to develop a three dimensional (3-D) porous bioresorbable scaffold with a biomimetic pore structure. Osseous healing and integration with the surrounding tissue depends in part on new blood vessel formation within the porous structure. Since endothelial cells play a key role in angiogenesis (formation of new blood vessels from pre-existing vasculature), the purpose of this study was to better understand human endothelial cell attachment, viability, growth, and phenotypic expression on sintered PLAGA microsphere scaffold. Scanning electron microscopy (SEM) examination showed cells attaching to the surface of microspheres and bridging the pores between the microspheres. Cell proliferation studies indicated that cell number increased during early stages and reached a plateau between days 10 and 14. Immunofluorescent staining for actin showed that cells were proliferating three dimensionally through the scaffolds while staining for PECAM-1 (platelet endothelial cell adhesion molecule) displayed typical localization at cell-cell contacts. Gene expression analysis showed that endothelial cells grown on PLAGA scaffolds maintained their normal characteristic phenotype. The cell proliferation and phenotypic expression were independent of scaffold pore architecture. These results demonstrate that PLAGA sintered microsphere scaffolds can support the growth and biological functions of human endothelial cells. The insights from this study should aid future studies aimed at enhancing angiogenesis in three dimensional tissue engineered scaffolds.  相似文献   

4.
Bone marrow is a useful cell source for skeletal tissue engineering approaches. In vitro differentiation of marrow mesenchymal stem cells (MSCs) to chondrocytes or osteoblasts can be induced by the addition of specific growth factors to the medium. The present study evaluated the behaviour of human MSCs cultured on various scaffolds to determine whether their differentiation can be induced by cell-matrix interactions. MSCs from bone marrow collected from the acetabulum during hip arthroplasty procedures were isolated by cell sorting, expanded and characterised by a flow cytometry system. Cells were grown on three different scaffolds (type I collagen, type I + II collagen and type I collagen + hydroxyapatite membranes) and analysed by histochemistry, immunohistochemistry and spectrophotometry (cell proliferation, alkaline phosphatase activity) at 15 and 30 days. Widely variable cell adhesion and proliferation was observed on the three scaffolds. MSCs grown on type I+II collagen differentiated to cells expressing chondrocyte markers, while those grown on type I collagen + hydroxyapatite differentiated into osteoblast-like cells. The study highlighted that human MSCs grown on different scaffold matrices may display different behaviours in terms of cell proliferation and phenotype expression without growth factor supplementation.  相似文献   

5.
目的建立热量限制的体外模型,观察不同能量培养条件下对人神经母细胞瘤细胞株SH-SY5Y细胞生长代谢的影响。方法将人神经母细胞瘤细胞株SH-SY5Y细胞分别采用含有低浓度(2 g/L)、正常浓度(3.15g/L)或高浓度(4.5 g/L)葡萄糖的培养基进行常规传代培养,利用MTT代谢率、细胞生长曲线及LDH漏出率等指标观察各组细胞生长情况。结果与正常葡萄糖浓度培养条件下培养的对照组相比,高糖组细胞突起缩短,细胞胞体皱缩,MTT代谢率稍低(0.573±0.001),LDH漏出率高,细胞生长状态差;与对照组相比,低糖组细胞突起伸展,MTT代谢率较低(0.428±0.003),LDH漏出率低,细胞生长速度缓慢,但是形态良好。结论高糖培养对细胞有损伤作用,细胞代谢加速,更容易衰老死亡;而低糖培养起到保护作用,在热量限制允许范围内降低培养液的含糖量,不但不会对细胞造成损伤,反而对细胞的代谢及生长起到保护作用,延长细胞的总体寿命。  相似文献   

6.
AFP or SA immobilized on nitrocellulose membranes (AFP-NC or SA-NC) were used as affinity matrices to purify cell membrane proteins with affinity for AFP (AFP-BP) and for SA (SA-BP) from membrane-enriched extracts of Raji cells (a B-lymphoma cell line), as well as for normal resting and activated peripheral blood lymphocytes (PBMC). SDS-PAGE and ligand blotting assays showed that AFP-BP and SA-BP isolated from Raji cells are probably identical molecules. They consisted of two sets of polypeptides of 31 kDa and 18 kDa. The glycoprotein nature of isolated 31 kDa and 18 kDa peptides was suggested by positive staining with Schiff's reagent, and amino-acid analysis revealed similar amino-acid composition for the two glycoproteins. In human PHA-activated PBMC, only the 18 kDa polypeptide was identified and isolated as AFP-BP or SA-BP. As in Raji cells, this 18 kDa polypeptide, isolated by affinity for AFP or for SA, appeared to be the same molecule. Contrary to Raji cells and activated PBMC, no proteins with an affinity for AFP or for SA were identified or isolated in resting PBMC. These observations strongly suggest that the isolated 31 kDa and 18 kDa glycoproteins are probably AFP receptors previously demonstrated in several neoplastic and normal cells undergoing growth and/or differentiation; indeed, they were identical to albumin-binding proteins described by others.  相似文献   

7.
目的:研究氨磷汀对体外培养的神经元样细胞的缺血再灌注损伤的保护作用,为其最终用于临床脑缺血的治疗打下基础。方法:体外培养的PC12细胞氧糖剥夺4h后复氧复糖,给予不同浓度的氨磷汀处理,20h后镜下观察细胞形态学变化,用MTT和LDH检测细胞活力和损伤情况,免疫荧光染色观察凋亡细胞,流式细胞仪计数凋亡细胞的比例。结果:高浓度氨磷汀对正常PC12细胞活力有抑制作用(P〈0.05),而低浓度则无。氨磷汀可以提高缺血再灌注损伤PC12细胞活力(P〈0.05),减少LDH释放(P〈0.05),保护细胞正常形态,抑制细胞凋亡(P〈0.05)。结论:氨磷汀对氧糖剥夺引起的神经元样细胞的缺血再灌注损伤具有保护作用。  相似文献   

8.
We describe here the use of Alta, a pre-existing scarlet-red stain of cosmetic use, for staining proteins on sodium dodecyl sulfate (SDS) polyacrylamide gels, as well as for a single step staining of gels and nitrocellulose membranes during Western blot analysis. This stain, which is composed of 0.8% Crocein scarlet (brilliant crocein) and 0.2% Rhodamine B, is inexpensive, easy to use and nearly as sensitive as Coomassie Brilliant Blue (CBB) R-250. The gels can be stained in 10% Alta (2 h) and can be destained effectively only with 7% acetic acid as opposed to the conventional destainer (methanol/acetic acid/water) required for CBB-stained gels. In an alternative procedure, the proteins can be stained on the gel while electrophoresis by simply using 5% Alta in the top tank buffer and the stain can be viewed under UV-transilluminator. This procedure can also be used for Western blot analysis, as a single step procedure for staining of proteins on the gel as well as on the nitrocellulose membrane, as the stain is retained on the membrane after protein transfer. Thus, this staining procedure allows monitoring of proteins after each step in the Western blot, thereby eliminating the need to run separate gels for staining and Western blot analysis, and also the need for Ponceau Red S staining of the nitrocellulose membrane during Western blot analysis.  相似文献   

9.
Influence of mechanical characteristics and matrix architecture of substrates used in cell culture is an important issue to tissue engineering. Chitosan‐based materials have been processed into porous structures, injectable gels and membranes, and are investigated to regenerate various tissues. However, the effect of these structures on cell growth and matrix production in accordance with each of the differing scaffolds has not been examined. We investigated the influence of porous structures, hydrogels, and membranes on the growth of normal human fibroblasts and their matrix production in a serum‐free system. We used chitosan alone and in combination with gelatin. Injectable hydrogels were prepared using 2‐glycerol phosphate. From the same solution, porous scaffolds and membranes were formed using controlled rate freezing and lyophilization, and air‐drying, respectively. Fibroblast growth was evaluated on the 4th and 10th days using flow cytometry and CFDA‐SE pre‐staining. Cell morphology was assessed using actin and nucleus staining. Total protein content, collagen, tropoelastin, and MMP2/MMP‐9 activity in the media supernatant were assessed by BCA, Sircol?, Fastin Elastin, and fluorogeneic peptide assays. Collagen accumulated in the matrix was assessed by Sircol? assay after pepsin/acetic acid digestion and by Masson's Trichrome staining. These results showed increased viability of fibroblasts on chitosan–gelatin porous scaffold with decreased proliferation relative to tissue culture plastic (TCP) surface despite the cells showing spindle shape. The total protein, collagen, and tropoelastin contents were higher in the spent media from chitosan–gelatin porous scaffolds compared to other conditions. MMP2/MMP9 activity was comparable to TCP. An increase in collagen content was also observed in the matrix, suggesting increased matrix deposition. In summary, matrix production is influenced by the form of chitosan structures, which significantly affects the regenerative process. Biotechnol. Bioeng. 2012; 109:1314–1325. © 2011 Wiley Periodicals, Inc.  相似文献   

10.
We studied the extracellular localization of factor VIII-related antigen (VIIIR: Ag) in cultures of human endothelial cells. The cells deposited both VIIIR: Ag and fibronectin already during their initial adhesion phase and in immunofluorescence microscopy of spread cells extracellular VIIIR: Ag was localized to fibrils coaligning with pericellular fibronectin. When human fibroblasts, which do not synthesize VIIIR: Ag, were cultured in endothelial cell post-culture medium, a fibrillar matrix localization of VIIIR: Ag was seen, comparable to that of endothelial cell cultures. A fibrillar VIIIR: Ag-specific staining was also seen in cell-free pericellular matrices of endothelial cells, produced by deoxycholate treatment. In immunoelectron microscopy, VIIIR: Ag was seen in fibrillar extracellular material between and underneath the cells and in cell-free matrices of endothelial cells as well.In immunofluorescence microscopy of cell-free matrices, VIIIR: Ag codistributed with both fibronectin and type III procollagen. Digestion of the matrices with purified bacterial collagenase abolished the type III procollagen-specific fluorescence, whereas the fibrillar VIIIR: Ag-specific staining, codistributing with fibronectin, remained unaffected. In electrophoresis of isolated, metabolically labelled endothelial cell matrices, major polypeptides with Mr 220–240; 180; 160; 80 and 45 kD and some minor polypeptides were resolved. In addition, immunoblotting revealed fibronectin, VIIIR: Ag and type III procollagen as components of cell-free matrices of endothelial cells. Direct overlay of iodinated cellular fibronectin on electrophoretically separated polypeptides of cultured endothelial cells, transferred to nitrocellulose, suggested that fibronectin binds directly to VIIIR: Ag. Our results indicate that VIIIR: Ag produced by human endothelial cells is a component of the pericellular matrix and is not bound to collagen but may directly associate with fibronectin.  相似文献   

11.
The cytotoxic effect of dehydroabietic acid (DHAA), a resin acid found in rosin, was studied on human polymorphonuclear leukocytes using leakage of 51Cr from prelabeled cells, supravital staining, and transmission electron microscopy. DHAA caused a strong dose-related release of 51Cr, a high uptake of trypan blue, and total cell necrosis, as seen in transmission electron microscopy. Albumin slightly reduced the toxic effects, whereas the addition of zinc in various forms strongly inhibited these toxic effects of DHAA in the concentration range of 10-500 micrograms/mL. In the presence of albumin, zinc oxide as a suspension inhibited the damage of the cell membranes more than a filtrate of zinc oxide, indicating a subsequent slow release of zinc from the zinc oxide.  相似文献   

12.
The cytotoxic effect of dehydroabietic acid (DHAA), a resin acid found in rosin, was studied on human polymorphonuclear leukocytes (PMN) using leakage of 51Cr from prelabeled cells, supravital staining, and transmission electron microscopy. DHAA caused a strong dose-related release of 51Cr, a high uptake of trypan blue, and total cell necrosis as seen in transmission electron microscopy. Albumin slightly reduced the toxic effects, whereas the addition of zinc in various forms strongly inhibited these toxic effects of DHAA in the concentration range 10-500 micrograms/mL. In the presence of albumin, zinc oxide as a suspension inhibited the damage of the cell membranes more than a filtrate of zinc oxide, indicating a subsequent slow release of zinc from the zinc oxide.  相似文献   

13.
为探讨胶原海绵对颌下腺 (submandibulargland ,SMG)导管细胞的细胞相容性 ,采用HE染色光镜观察及免疫组化观察SMG导管细胞接种于胶原海绵后 ,细胞的生长情况。光镜下可见接种后第 1d细胞数量较少 ,分散于胶原海绵支架中间 ,第 7d细胞数量明显增加 ,免疫组织化学染色抗IV型胶原抗体染色呈阳性 ,说明细胞与支架材料之间已经有细胞外基质产生。胶原海绵具有良好的细胞相容性 ,是一种理想的支架材料。与胶原海绵复合培养 ,颌下腺导管细胞仍可保持良好的增殖能力。  相似文献   

14.
Electrospun nanocomposite scaffolds were fabricated by encapsulating multi-walled carbon nanotubes (MWNT) in poly (lactic acid) (PLA) nanofibers. Scanning electron microscopy (SEM) confirmed the fabrication of nanofibers, and transmission electron microscopy identified the alignment and dispersion of MWNT along the axis of the fibers. Tensile testing showed an increase in the tensile modulus for a MWNT loading of 0.25 wt% compared with electrospun nanofibrous mats without MWNT reinforcement. Conductivity measurements indicated that the confined geometry of the fibrous system requires only minute doping to obtain significant enhancements at 0.32 wt%. Adipose-derived human mesenchymal stem cells (hMSCs) were seeded on electrospun scaffolds containing 1 wt% MWNT and 0 wt% MWNT, to determine the efficacy of the scaffolds for cell growth, and the effect of MWNT on hMSC viability and proliferation over two weeks in culture. Staining for live and dead cells and DNA quantification indicated that the hMSCs were alive and proliferating through day 14. SEM images of hMSCs at 14 days showed morphological differences, with hMSCs on PLA well spread and hMSCs on PLA with 1% MWNT closely packed and longitudinally aligned.  相似文献   

15.
壳聚糖基角膜细胞载体的制备及其细胞相容性   总被引:1,自引:0,他引:1  
为探讨羟丙基壳聚糖基共混膜作为组织工程技术中角膜细胞培养载体的可行性, 分别制备了羟丙基壳聚糖/硫酸软骨素、羟丙基壳聚糖/明胶/硫酸软骨素以及羟丙基壳聚糖/氧化透明质酸/硫酸软骨素三种共混膜。测定其透光率、含水量和蛋白吸附性能; 在共混膜上培养兔角膜上皮细胞, 通过观察角膜上皮细胞在不同载体膜上的生长状态、贴附情况, 测定细胞活性以及上清液中乳酸脱氢酶的活性, 研究三种壳聚糖基载体膜片与角膜上皮细胞的相容性。膜片理化性质测定结果表明三种共混膜片具有良好的透明度, 适宜的含水量和较强的蛋白吸附性能; 细胞相容性实验结果表明羟丙基壳聚糖/明胶/硫酸软骨素共混膜对细胞的损伤最小, 有利于细胞在膜上的贴附和生长, 表现出良好的细胞相容性, 有望作为角膜细胞载体体外构建组织工程化角膜。  相似文献   

16.
The spatial cell-material interaction remains vital issue in forming biodegradable scaffolds in Tissue Engineering. In this study, to understand the influence of spatial architecture on cellular behavior, 2D and 3D chitosan scaffolds of 50-190 kD and >310 kD MW were synthesized through air drying and controlled rate freezing/lypohilization technique, respectively. In addition, chitosan was emulsified with 19, 76, and 160 kD 50:50 poly lactide-co-glycolide (PLGA) using 1,2-Dimyristoyl-sn-Glycero-3-Phosphocholine (DMPC) as stabilizer. 2D and 3D scaffolds were formed by air drying and lyophilization as before. Tensile and compressive properties of films and scaffolds were analyzed in wet conditions at 37 degrees C. Alterations in the cell spreading, proliferation, and cytoskeletal organization of human umbilical vein endothelial cells (HUVECs) and mouse embryonic fibroblasts (MEFs) were studied. These results showed that the formed 3D chitosan scaffolds had interconnected open pore architecture (50-200 microm size). HUVECs and MEFs had reduced spreading areas and circular morphology on 2D chitosan membranes compared with 3D chitosan scaffolds. The fluorescence photomicrographs for actin (using Alexa Fluor 488 phalloidin) and cytoplasm staining (using carboxyfluorescein diacetate-succinimidyl ester) demonstrated that the cells spread within 3D chitosan matrix. 2D and 3D emulsified chitosan and chitosan/PLGA scaffolds reduced the spreading of HUVECs and MEFs even further. Proliferation results, analyzed via MTT-Formazan assay and BrdU uptake assay, correlated with the spreading characteristics. The reductions in cell spreading area on emulsified surfaces were not detrimental to the viability and endocytic activity but to proliferation. The observed alterations in cellular colonization are in part due to the substrate stiffness and surface topography. In summary, these results suggest a significant influence of spatial architecture on cellular colonization.  相似文献   

17.
Epithelial cells require adherence to a matrix for regular growth. During standard keratinocyte cell culture in serum-free medium, we observed that cell colonies formed not only on the bottom of the culture vessels but also at the medium/air interface. Coomassie blue staining detected a protein membrane that extended up to several centimeters between the colonies of floating cells. Ultrastructural investigation of this membrane revealed structures closely resembling those of basement membranes, and immunochemical staining confirmed the presence of laminins-1 and -5 as well as collagen IV, representative components of basement membranes. Cells attached to the floating membrane proliferated and could be cultivated for up to six months. When keratinocyte-conditioned medium was filtered and transferred to a culture vessel without cells, the protein membrane at the liquid/air interface formed within one week suggesting self-assembly of cell-released proteins. Our findings provide a basis for the production of epidermal basement membranes for potential medical uses.  相似文献   

18.
Our aim was to study how mouse skeletal muscle membranes are altered by eccentric and isometric contractions. A fluorescent dialkyl carbocyanine dye (DiOC18(3)) was used to label muscle membranes, and the membranes accessible to the dye were observed by confocal laser scanning microscopy. Experiments were done on normal mouse soleus muscles and soleus muscles injured by 20 eccentric or 20 isometric contractions. Longitudinal optical sections of control muscle fibers revealed DiOC18(3) staining of the plasmalemma and regularly spaced transverse bands corresponding in location to the T-tubular system. Transverse optical sections showed an extensive reticular network with the DiOC18(3) staining. Injured muscle fibers showed distinctively different staining patterns in both longitudinal and transverse optical sections. Longitudinal optical sections of the injured fibers revealed staining in a longitudinally-oriented pattern. No correlations were found between the abnormal DiOC18(3) staining and the reductions in maximal isometric tetanic force or release of lactate dehydrogenase (P0.32). Additionally, no difference in the extent of abnormal staining was found between muscles performing eccentric contractions and those performing the less damaging isometric contractions. However, many fibers in muscles injured by eccentric contractions showed swollen regions with marked loss of membrane integrity and an elevated free cytosolic calcium concentration as observed in Fluo-3 images. In conclusion, a loss of cell membrane integrity results from contractile activity, enabling DiOC18(3) staining of internal membranes. The resulting staining pattern is striking and fibers with damaged cell membranes are easily distinguished from uninjured ones.  相似文献   

19.
We report on the feasibility of applying porous gelatin hydrogels, prepared by a novel and controlled cryogenic treatment, as cell-interactive scaffolds for tissue engineering applications. Despite the large number of publications on gelatin as a biomaterial, a detailed study of screening a limited number of gelatin scaffolds for their interaction with a panel of human cells has, to the best of our knowledge, not yet been published. In the present work, we have evaluated two types of porous gelatin scaffolds that differ in their pore geometry and pore size. Type I hydrogels contained top-to-bottom transverse channels (i.e. cones) with a decreasing diameter from the top (330 microm) to the bottom (20-30 microm). Type II hydrogels contained spherical pores with a diameter of 135 microm. Both types of scaffolds were evaluated by confocal laser scanning microscopy in terms of adhesion, spreading, and proliferation of human cells (endothelial, epithelial, fibroblast, glial, and osteoblast) by visualizing cells using calcein-acetoxy methyl ester as a vital stain. The results indicated that cells attached, spread, and proliferated on both types of hydrogels. In addition, the scaffolds developed can be used for the long-term culturing of human cells.  相似文献   

20.
Background: The use of polymer-based delivery systems, on which cells are cultured and transferred, improves the ease of handling and transfer of the keratinocytes. A transparent polymer also allows observation of cell growth prior to grafting as well as re-epithelialization after grafting to the wound. We have developed techniques for cultured keratinocytes on TegadermTM (3M), an inexpensive and easily available polyurethane-based wound dressing, for treatment of burn and chronic wounds. In this study, we evaluate cell culture characteristics of three different cell types, human epidermal keratinocytes, human dermal fibroblasts and pig bone marrow mesenchymal stem cells on Tegaderm membrane. Methods: Cells were isolated from human skin or pig bone marrow and cultured on membranes for a period of five days. Cell proliferation was assessed by colorimetric assay (MTT) and scanning electron microscopy. Results and conclusions: This study confirms that Tegaderm membranes support attachment and growths for these cell types, with those growth characteristics are similar, if not as good as that of optimal condition of tissue culture plastics. Data from our study suggest that Tegaderm membranes can be used, modified and developed further as an economical and easily available material for tissue engineered skin.  相似文献   

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