Radiosensitivity of normal human epidermal cells in culture

International Nuclear Information System (INIS)

Dover, R.; Potten, C.S.

1983-01-01

Using an in vitro culture system the authors have derived #betta#-radiation survival curves over a dose range 0-8 Gy for the clonogenic cells of normal human epidermis. The culture system used allows the epidermal cells to stratify and form a multi-layered sheet of keratinizing cells. The cultures appear to be a very good model for epidermis in vivo. The survival curves show a population which is apparently more sensitive than murine epidermis in vivo. It remains unclear whether this is an intrinsic difference between the species or is a consequence of the in vitro cultivation of the human cells. (author)

Effect of X-Rays on Growth Rate of Rose Shoot Cultures and the Ability of Isolated Protoplasts to Form Cell Colonies

International Nuclear Information System (INIS)

Moustafa, R. A. K.

2004-01-01

The popularity of rose as a garden plant, allied with its use in the production of cut flowers and also as a source of aromatic rose oils, make it one of the most important ornamental crops. Roses, however, have suffered from a narrow genetic base to which only few species have contributed significantly. In vitro culture of plants might facilitate the improvement of rose via the exploitation of somaclonal variation to generate new genetic variability and selection within the variation for desirable traits. The application of mutagens for in vitro cultures, in addition to the induced mutations, may lead to increase the somaclonal variation, thus providing additional variation for selection. On the other hand, plant protoplasts offer exciting possibilities to establish in vitro selection programs based on single cells. Induced variation in isolated protoplasts using mutagen agents may be one mean to select useful mutants. Thus the present experiments were conducted to determine the effect of X-rays on shoot cultures and the isolated protoplasts of rose (Rosa sp.). The materials consisted of the three rose varieties Rosa wichuriana, Paricer charm and Heckenzauber.The applied doses were 0, 10, 20, 30, 40, 50 and 60 Gy. Obtained results indicated that the genotypes differed in their sensitivity to X-rays. Rosa wichuriana seemed to be the most sensitive variety to radiation, where a dose of 20 Gy caused approximately 50% reduction in growth rate of shoot cultures, while the same dose decreased the growth rate of Paricer charm only by 25% and did not affect the growth of Heckenzauber. Results also revealed that the ability of irradiated protoplasts to form cell colonies increased when a dose of 10 Gy was performed. Doses higher than that level caused gradual decreasing in the forming of cell colonies, but however, the protoplasts could form colonies even when a dose of 60 Gy was applied. (Author)

Nanotechnology, Cell Culture and Tissue Engineering

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Kazutoshi Haraguchi

2011-01-01

Full Text Available We have fabricated new types of polymer hydrogels and polymer nanocomposites, i.e., nanocomposite gels (NC gels and soft, polymer nanocomposites (M-NCs: solid, with novel organic/inorganic network structures. Both NC gels and M-NCs were synthesized by in-situ free-radical polymerization in the presence of exfoliated clay platelets in aqueous systems and were obtained in various forms such as film, sheet, tube, coating, etc. and sizes with a wide range of clay contents. Here, disk-like inorganic clay nanoparticles act as multi-functional crosslinkers to form new types of network systems. Both NC gels and M-NCs have extraordinary optical and mechanical properties including ultra-high reversible extensibility, as well as a number of new characteristics relating to optical anisotropy, polymer/clay morphology, biocompatibility, stimuli-sensitive surfaces, micro-patterning, etc. For examples, the biological testing of medical devices, comprised of a sensitization test, an irritation test, an intracutaneous test and an in vitro cytotoxicity test,was carried out for NC gels and M-NCs. The safety of NC gels and M-NCs was confirmed in all tests. Also, the interaction of living tissue with NC gel was investigated in vivo by implantation in live goats; neither inflammation nor concrescence occurred around the NC gels. Furthermore, it was found that both N-NC gels consisting of poly(N-isopropylacrylamide(PNIPA/clay network and M-NCs consisting of poly(2-methoxyethyacrylate(PMEA/clay network show characteristic cell culture and subsequent cell detachment on their surfaces, although it was almost impossible to culture cells on conventional, chemically-crosslinked PNIPA hydrogels and chemically crossslinked PMEA, regardless of their crosslinker concentration. Various kinds of cells, such ashumanhepatoma cells (HepG2, normal human dermal fibroblast (NHDF, and human umbilical vein endothelial cells (HUVEC, could be cultured to be confluent on the surfaces of N

A microwell cell culture platform for the aggregation of pancreatic β-cells.

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Bernard, Abigail B; Lin, Chien-Chi; Anseth, Kristi S

2012-08-01

Cell-cell contact between pancreatic β-cells is important for maintaining survival and normal insulin secretion. Various techniques have been developed to promote cell-cell contact between β-cells, but a simple yet robust method that affords precise control over three-dimensional (3D) β-cell cluster size has not been demonstrated. To address this need, we developed a poly(ethylene glycol) (PEG) hydrogel microwell platform using photolithography. This microwell cell-culture platform promotes the formation of 3D β-cell aggregates of defined sizes from 25 to 210 μm in diameter. Using this platform, mouse insulinoma 6 (MIN6) β-cells formed aggregates with cell-cell adherin junctions. These naturally formed cell aggregates with controllable sizes can be removed from the microwells for macroencapsulation, implantation, or other biological assays. When removed and subsequently encapsulated in PEG hydrogels, the aggregated cell clusters demonstrated improved cellular viability (>90%) over 7 days in culture, while the β-cells encapsulated as single cells maintained only 20% viability. Aggregated MIN6 cells also exhibited more than fourfold higher insulin secretion in response to a glucose challenge compared with encapsulated single β-cells. Further, the cell aggregates stained positively for E-cadherin, indicative of the formation of cell junctions. Using this hydrogel microwell cell-culture method, viable and functional β-cell aggregates of specific sizes were created, providing a platform from which other biologically relevant questions may be answered.

3D cellular structures and co-cultures formed through the contactless magnetic manipulation of cells on adherent surfaces.

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Abdel Fattah, Abdel Rahman; Mishriki, Sarah; Kammann, Tobias; Sahu, Rakesh P; Geng, Fei; Puri, Ishwar K

2018-02-27

A magnet array is employed to manipulate diamagnetic cells that are contained in paramagnetic medium to demonstrate for the first time the contactless bioprinting of three-dimensional (3D) cellular structures and co-cultures of breast cancer MCF-7 and endothelial HUVEC at prescribed locations on tissue culture treated well plates. Sequential seeding of different cell lines and the spatial displacement of the magnet array creates co-cultured cellular structures within a well without using physically intrusive well inserts. Both monotypic and co-culture experiments produce morphologically rich 3D cell structures that are otherwise absent in regular monolayer cell cultures. The magnetic contactless bioprinting of cells provides further insight into cell behaviour, invasion strategies and transformations that are useful for potential applications in drug screening, 3D cell culture formation and tissue engineering.

Pock forming ability of fowl pox virus isolated from layer chicken and its adaptation in chicken embryo fibroblast cell culture.

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Gilhare, Varsha Rani; Hirpurkar, S D; Kumar, Ashish; Naik, Surendra Kumar; Sahu, Tarini

2015-03-01

The objective of the present study was to examine pock forming ability of field strain and vaccine strain of fowl pox virus (FPV) in chorioallantoic membrane (CAM) of embryonated chicken eggs and its adaptation in chicken embryo fibroblast (CEF) cell culture. Dry scabs were collected from 25 affected birds in glycerin-saline and preserved at 4°C until processed. Virus was isolated in 10-day-old embryonated chicken eggs by dropped CAM method. The identity of the virus is confirmed by clinical findings of affected birds, pock morphology and histopathology of infected CAM. In addition one field isolate and vaccine strain of FPV was adapted to CEF cell culture. CEF cell culture was prepared from 9-day-old embryonated chicken eggs. Clinical symptoms observed in affected birds include pox lesion on comb, wattle, eyelids and legs, no internal lesions were observed. All field isolates produced similar findings in CAM. Pocks produced by field isolates ranged from 3 mm to 5 mm at the third passage while initial passages edematous thickening and necrosis of CAM was observed. Pocks formed by lyophilized strain were ranges from 0.5 mm to 2.5 mm in diameter scattered all over the membrane at the first passage. Intra-cytoplasmic inclusion bodies are found on histopathology of CAM. At third passage level, the CEF inoculated with FPV showed characteristic cytopathic effect (CPE) included aggregation of cells, syncytia and plaque formation. FPV field isolates and vaccine strain produced distinct pock lesions on CAMs. Infected CAM showed intracytoplasmic inclusion bodies. The CEF inoculated with FPV field isolate as well as a vaccine strain showed characteristic CPE at third passage level.

Insect Cell Culture

NARCIS (Netherlands)

Oers, van M.M.; Lynn, D.E.

2010-01-01

Insect cell cultures are widely used in studies on insect cell physiology, developmental biology and microbial pathology. In particular, insect cell culture is an indispensable tool for the study of insect viruses. The first continuously growing insect cell cultures were established from

Biosynthesis of 14C-phytoene from tomato cell suspension cultures (Lycopersicon esculentum) for utilization in prostate cancer cell culture studies.

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Campbell, Jessica K; Rogers, Randy B; Lila, Mary Ann; Erdman, John W

2006-02-08

This work describes the development and utilization of a plant cell culture production approach to biosynthesize and radiolabel phytoene and phytofluene for prostate cancer cell culture studies. The herbicide norflurazon was added to established cell suspension cultures of tomato (Lycopersicon esculentum cv. VFNT cherry), to induce the biosynthesis and accumulation of the lycopene precursors, phytoene and phytofluene, in their natural isomeric forms (15-cis-phytoene and two cis-phytofluene isomers). Norflurazon concentrations, solvent carrier type and concentration, and duration of culture exposure to norflurazon were screened to optimize phytoene and phytofluene synthesis. Maximum yields of both phytoene and phytofluene were achieved after 7 days of treatment with 0.03 mg norflurazon/40 mL fresh medium, provided in 0.07% solvent carrier. Introduction of 14C-sucrose to the tomato cell culture medium enabled the production of 14C-labeled phytoene for subsequent prostate tumor cell uptake studies. In DU 145 prostate tumor cells, it was determined that 15-cis-phytoene and an oxidized product of phytoene were taken up and partially metabolized by the cells. The ability to biosynthesize, radiolabel, and isolate these carotenoids from tomato cell cultures is a novel, valuable methodology for further in vitro and in vivo investigations into the roles of phytoene and phytofluene in cancer chemoprevention.

AMMONIA REMOVAL FROM MAMMALIAN CELL CULTURE MEDIUM BY ION-EXCHANGE MEMBRANES

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Metabolites such as ammonia and lactic acid formed during mammalian cell culture can frequently be toxic to the cells themselves beyond a threshold concentration of the metabolites. Cell culture conducted in the presence of such accumulated metabolites is therefore limited in pro...

A method for culturing human hair follicle cells.

Science.gov (United States)

Weterings, P J; Vermorken, A J; Bloemendal, H

1981-01-01

For the first time a method for culturing human hair follicle cells is described. The bovine eye lens capsule, a basement membrane-like structure, is used as the substrate for the cultures. In a culture medium supplemented with hydrocortisone and insulin about 70% of the original follicles will form growing colonies of diploid keratinocytes.

Progenitor cells in auricular cartilage demonstrate cartilage-forming capacity in 3D hydrogel culture

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IA Otto

2018-02-01

Full Text Available Paramount for the generation of auricular structures of clinically-relevant size is the acquisition of a large number of cells maintaining an elastic cartilage phenotype, which is the key in producing a tissue capable of withstanding forces subjected to the auricle. Current regenerative medicine strategies utilize chondrocytes from various locations or mesenchymal stromal cells (MSCs. However, the quality of neo-tissues resulting from these cell types is inadequate due to inefficient chondrogenic differentiation and endochondral ossification, respectively. Recently, a subpopulation of stem/progenitor cells has been identified within the auricular cartilage tissue, with similarities to MSCs in terms of proliferative capacity and cell surface biomarkers, but their potential for tissue engineering has not yet been explored. This study compared the in vitro cartilage-forming ability of equine auricular cartilage progenitor cells (AuCPCs, bone marrow-derived MSCs and auricular chondrocytes in gelatin methacryloyl (gelMA-based hydrogels over a period of 56 d, by assessing their ability to undergo chondrogenic differentiation. Neocartilage formation was assessed through gene expression profiling, compression testing, biochemical composition and histology. Similar to MSCs and chondrocytes, AuCPCs displayed a marked ability to generate cartilaginous matrix, although, under the applied culture conditions, MSCs outperformed both cartilage-derived cell types in terms of matrix production and mechanical properties. AuCPCs demonstrated upregulated mRNA expression of elastin, low expression of collagen type X and similar levels of proteoglycan production and mechanical properties as compared to chondrocytes. These results underscored the AuCPCs’ tissue-specific differentiation potential, making them an interesting cell source for the next generation of elastic cartilage tissue-engineered constructs.

Osteogenic medium is superior to growth factors in differentiation of human adipose stem cells towards bone-forming cells in 3D culture

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L Tirkkonen

2013-01-01

Full Text Available Human adipose stem cells (hASCs have been recently used to treat bone defects in clinical practice. Yet there is a need for more optimal scaffolds and cost-effective approaches to induce osteogenic differentiation of hASCs. Therefore, we compared the efficiency of bone morphogenetic proteins (BMP-2 and BMP-7, vascular endothelial growth factor (VEGF, and osteogenic medium (OM for the osteo-induction of hASCs in 3D culture. In addition, growth factors were tested in combination with OM. Commercially available bioactive glass scaffolds (BioRestore and biphasic calcium phosphate granules (BoneCeramic were evaluated as prospective carriers for hASCs. Both biomaterials supported hASC-viability, but BioRestore resulted in higher cell number than BoneCeramic, whereas BoneCeramic supported more significant collagen production. The most efficient osteo-induction was achieved with plain OM, promoting higher alkaline phosphatase activity and collagen production than growth factors. In fact, treatment with BMP-2 or VEGF did not increase osteogenic differentiation or cell number significantly more than maintenance medium with either biomaterial. Moreover, BMP-7 treatment consistently inhibited proliferation and osteogenic differentiation of hASCs. Interestingly, there was no benefit from growth factors added to OM. This is the first study to demonstrate that OM enhances hASC-differentiation towards bone-forming cells significantly more than growth factors in 3D culture.

Aragonite precipitation by "proto-polyps" in coral cell cultures.

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Tali Mass

Full Text Available The mechanisms of coral calcification at the molecular, cellular and tissue levels are poorly understood. In this study, we examine calcium carbonate precipitation using novel coral tissue cultures that aggregate to form "proto-polyps". Our goal is to establish an experimental system in which calcification is facilitated at the cellular level, while simultaneously allowing in vitro manipulations of the calcifying fluid. This novel coral culturing technique enables us to study the mechanisms of biomineralization and their implications for geochemical proxies. Viable cell cultures of the hermatypic, zooxanthellate coral, Stylophora pistillata, have been maintained for 6 to 8 weeks. Using an enriched seawater medium with aragonite saturation state similar to open ocean surface waters (Ω(arag~4, the primary cell cultures assemble into "proto-polyps" which form an extracellular organic matrix (ECM and precipitate aragonite crystals. These extracellular aragonite crystals, about 10 µm in length, are formed on the external face of the proto-polyps and are identified by their distinctive elongated crystallography and X-ray diffraction pattern. The precipitation of aragonite is independent of photosynthesis by the zooxanthellae, and does not occur in control experiments lacking coral cells or when the coral cells are poisoned with sodium azide. Our results demonstrate that proto-polyps, aggregated from primary coral tissue culture, function (from a biomineralization perspective similarly to whole corals. This approach provides a novel tool for investigating the biophysical mechanism of calcification in these organisms.

Immunohistochemical detection of cytochrome P450 isoenzymes in cultured human epidermal cells.

Science.gov (United States)

Van Pelt, F N; Meierink, Y J; Blaauboer, B J; Weterings, P J

1990-12-01

We used specific monoclonal antibodies (MAb) to human cytochrome P450 isoenzymes to determine the presence of these proteins in human epidermal cells. Two MAb (P450-5 and P450-8) recognize major forms of hepatic cytochrome P450 involved in biotransformation of xenobiotics. A third MAb, to cytochrome P450-9, is not fully characterized. The proteins were determined by the indirect immunoperoxidase technique after fixation with methanol and acetone. Biopsy materials for cultured keratinocytes, i.e., foreskin and hair follicles, contained the two major forms of cytochrome P450. In cultured keratinocytes derived from hair follicles the proteins were undetectable, whereas the keratinocytes derived from foreskin continued to express the two major forms of hepatic cytochrome P450. Cultured human fibroblasts and a human keratinocyte cell line (SVK14) showed staining similar to that of the foreskin keratinocytes. Cytochrome P450-9 was detectable only in human hepatocytes. The results indicate that, under the culture conditions applied, cultured human foreskin cells and the cell line SVK14 continue to express specific cytochrome P450 isoenzymes in culture, in contrast to hair follicle keratinocytes.

In vitro assays for cobblestone area-forming cells, LTC-IC, and CFU-C

NARCIS (Netherlands)

van Os, Ronald P; Dethmers-Ausema, Bertien; de Haan, Gerald; Bunting, Kevin

2008-01-01

Various assays exist that measure the function of hematopoietic stemcells (HSCs). In this chapter, in vitro assays are described that measure the frequency of progenitors (colony-forming unit in culture; CFU-C), stem cells (long-term culture-initiating cell; LTC-IC), or both (cobblestone

Multizone Paper Platform for 3D Cell Cultures

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Derda, Ratmir; Hong, Estrella; Mwangi, Martin; Mammoto, Akiko; Ingber, Donald E.; Whitesides, George M.

2011-01-01

In vitro 3D culture is an important model for tissues in vivo. Cells in different locations of 3D tissues are physiologically different, because they are exposed to different concentrations of oxygen, nutrients, and signaling molecules, and to other environmental factors (temperature, mechanical stress, etc). The majority of high-throughput assays based on 3D cultures, however, can only detect the average behavior of cells in the whole 3D construct. Isolation of cells from specific regions of 3D cultures is possible, but relies on low-throughput techniques such as tissue sectioning and micromanipulation. Based on a procedure reported previously (“cells-in-gels-in-paper” or CiGiP), this paper describes a simple method for culture of arrays of thin planar sections of tissues, either alone or stacked to create more complex 3D tissue structures. This procedure starts with sheets of paper patterned with hydrophobic regions that form 96 hydrophilic zones. Serial spotting of cells suspended in extracellular matrix (ECM) gel onto the patterned paper creates an array of 200 micron-thick slabs of ECM gel (supported mechanically by cellulose fibers) containing cells. Stacking the sheets with zones aligned on top of one another assembles 96 3D multilayer constructs. De-stacking the layers of the 3D culture, by peeling apart the sheets of paper, “sections” all 96 cultures at once. It is, thus, simple to isolate 200-micron-thick cell-containing slabs from each 3D culture in the 96-zone array. Because the 3D cultures are assembled from multiple layers, the number of cells plated initially in each layer determines the spatial distribution of cells in the stacked 3D cultures. This capability made it possible to compare the growth of 3D tumor models of different spatial composition, and to examine the migration of cells in these structures. PMID:21573103

3D tissue formation by stacking detachable cell sheets formed on nanofiber mesh.

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Kim, Min Sung; Lee, Byungjun; Kim, Hong Nam; Bang, Seokyoung; Yang, Hee Seok; Kang, Seong Min; Suh, Kahp-Yang; Park, Suk-Hee; Jeon, Noo Li

2017-03-23

We present a novel approach for assembling 3D tissue by layer-by-layer stacking of cell sheets formed on aligned nanofiber mesh. A rigid frame was used to repeatedly collect aligned electrospun PCL (polycaprolactone) nanofiber to form a mesh structure with average distance between fibers 6.4 µm. When human umbilical vein endothelial cells (HUVECs), human foreskin dermal fibroblasts, and skeletal muscle cells (C2C12) were cultured on the nanofiber mesh, they formed confluent monolayers and could be handled as continuous cell sheets with areas 3 × 3 cm 2 or larger. Thicker 3D tissues have been formed by stacking multiple cell sheets collected on frames that can be nested (i.e. Matryoshka dolls) without any special tools. When cultured on the nanofiber mesh, skeletal muscle, C2C12 cells oriented along the direction of the nanofibers and differentiated into uniaxially aligned multinucleated myotube. Myotube cell sheets were stacked (upto 3 layers) in alternating or aligned directions to form thicker tissue with ∼50 µm thickness. Sandwiching HUVEC cell sheets with two dermal fibroblast cell sheets resulted in vascularized 3D tissue. HUVECs formed extensive networks and expressed CD31, a marker of endothelial cells. Cell sheets formed on nanofiber mesh have a number of advantages, including manipulation and stacking of multiple cell sheets for constructing 3D tissue and may find applications in a variety of tissue engineering applications.

Surface modified alginate microcapsules for 3D cell culture

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Chen, Yi-Wen; Kuo, Chiung Wen; Chueh, Di-Yen; Chen, Peilin

2016-06-01

Culture as three dimensional cell aggregates or spheroids can offer an ideal platform for tissue engineering applications and for pharmaceutical screening. Such 3D culture models, however, may suffer from the problems such as immune response and ineffective and cumbersome culture. This paper describes a simple method for producing microcapsules with alginate cores and a thin shell of poly(L-lysine)-graft-poly(ethylene glycol) (PLL-g-PEG) to encapsulate mouse induced pluripotent stem (miPS) cells, generating a non-fouling surface as an effective immunoisolation barrier. We demonstrated the trapping of the alginate microcapsules in a microwell array for the continuous observation and culture of a large number of encapsulated miPS cells in parallel. miPS cells cultured in the microcapsules survived well and proliferated to form a single cell aggregate. Droplet formation of monodisperse microcapsules with controlled size combined with flow cytometry provided an efficient way to quantitatively analyze the growth of encapsulated cells in a high-throughput manner. The simple and cost-effective coating technique employed to produce the core-shell microcapsules could be used in the emerging field of cell therapy. The microwell array would provide a convenient, user friendly and high-throughput platform for long-term cell culture and monitoring.

Cell Culture in Microgravity: Opening the Door to Space Cell Biology

Science.gov (United States)

Pellis, Neal R.; Dawson, David L. (Technical Monitor)

1999-01-01

Adaptational response of human cell populations to microgravity is investigated using simulation, short-term Shuttle experiments, and long-term microgravity. Simulation consists of a clinostatically-rotated cell culture system. The system is a horizontally-rotated cylinder completely filled with culture medium. Low speed rotation results in continuous-fall of the cells through the fluid medium. In this setting, cells: 1) aggregate, 2) propagate in three dimensions, 3) synthesize matrix, 4) differentiate, and 5) form sinusoids that facilitate mass transfer. Space cell culture is conducted in flight bioreactors and in static incubators. Cells grown in microgravity are: bovine cartilage, promyelocytic leukemia, kidney proximal tubule cells, adrenal medulla, breast and colon cancer, and endothelium. Cells were cultured in space to test specific hypotheses. Cartilage cells were used to determine structural differences in cartilage grown in space compared to ground-based bioreactors. Results from a 130-day experiment on Mir revealed that cartilage grown in space was substantially more compressible due to insufficient glycosaminoglycan in the matrix. Interestingly, earth-grown cartilage conformed better to the dimensions of the scaffolding material, while the Mir specimens were spherical. The other cell populations are currently being analyzed for cell surface properties, gene expression, and differentiation. Results suggest that some cells spontaneously differentiate in microgravity. Additionally, vast changes in gene expression may occur in response to microgravity. In conclusion, the transition to microgravity may constitute a physical perturbation in cells resulting in unique gene expressions, the consequences of which may be useful in tissue engineering, disease modeling, and space cell biology.

Rotary orbital suspension culture of embryonic stem cell-derived neural stem/progenitor cells: impact of hydrodynamic culture on aggregate yield, morphology and cell phenotype.

Science.gov (United States)

Laundos, Tiago L; Silva, Joana; Assunção, Marisa; Quelhas, Pedro; Monteiro, Cátia; Oliveira, Carla; Oliveira, Maria J; Pêgo, Ana P; Amaral, Isabel F

2017-08-01

Embryonic stem (ES)-derived neural stem/progenitor cells (ES-NSPCs) constitute a promising cell source for application in cell therapies for the treatment of central nervous system disorders. In this study, a rotary orbital hydrodynamic culture system was applied to single-cell suspensions of ES-NSPCs, to obtain homogeneously-sized ES-NSPC cellular aggregates (neurospheres). Hydrodynamic culture allowed the formation of ES-NSPC neurospheres with a narrower size distribution than statically cultured neurospheres, increasing orbital speeds leading to smaller-sized neurospheres and higher neurosphere yield. Neurospheres formed under hydrodynamic conditions (72 h at 55 rpm) showed higher cell compaction and comparable percentages of viable, dead, apoptotic and proliferative cells. Further characterization of cellular aggregates provided new insights into the effect of hydrodynamic shear on ES-NSPC behaviour. Rotary neurospheres exhibited reduced protein levels of N-cadherin and β-catenin, and higher deposition of laminin (without impacting fibronectin deposition), matrix metalloproteinase-2 (MMP-2) activity and percentage of neuronal cells. In line with the increased MMP-2 activity levels found, hydrodynamically-cultured neurospheres showed higher outward migration on laminin. Moreover, when cultured in a 3D fibrin hydrogel, rotary neurospheres generated an increased percentage of neuronal cells. In conclusion, the application of a constant orbital speed to single-cell suspensions of ES-NSPCs, besides allowing the formation of homogeneously-sized neurospheres, promoted ES-NSPC differentiation and outward migration, possibly by influencing the expression of cell-cell adhesion molecules and the secretion of proteases/extracellular matrix proteins. These findings are important when establishing the culture conditions needed to obtain uniformly-sized ES-NSPC aggregates, either for use in regenerative therapies or in in vitro platforms for biomaterial development or

Cell division requirement for activation of murine leukemia virus in cell culture by irradiation

International Nuclear Information System (INIS)

Otten, J.A.; Quarles, J.M.; Tennant, R.W.

1976-01-01

Actively dividing cultures of AKR mouse cells were exposed to relatively low dose-rates of γ radiation and tested for activation of endogenous leukemia viruses. Efficient and reproducible induction of virus was obtained with actively dividing cells, but cultures deprived of serum to inhibit cell division before and during γ irradiation were not activated, even when medium with serum was added immediately after irradiation. These results show that cell division was required for virus induction but that a stable intermediate similar to the state induced by halogenated pyrimidines was not formed. In actively dividing AKR cell cultures, virus activation appeared to be proportional to the dose of γ radiation; the estimated frequency of activation was 1-8 x 10 - 5 per exposed cell and the efficiency of activation was approximately 0.012 inductions per cell per rad. Other normal primary and established mouse cell cultures tested were not activated by γ radiation. The requirement of cell division for radiation and chemical activation may reflect some common mechanism for initiation of virus expression

Plant Cell Culture Initiation: practical tips

NARCIS (Netherlands)

Hall, R.D.

2001-01-01

The use of cultured plant cells in either organized or unorganized form has increased vey considerably in the last 10-15 yr. Many new technologies have been developed and applications in both fundamental and applied research have led to the development of some powerful tools for improving our

Loss of the ability to generate large burst-forming unit-like megakaryocytic colonies from thawed cord blood in semisolid cultures after short term suspension culture.

Science.gov (United States)

Eskola, M; Bäckman, S; Möttönen, S; Kekomäki, R

2015-04-01

Total colony-forming cells from thawed cord blood units (CBUs) include megakaryocytic colony-forming units (CFU-Mks), which survive the freezing process. The aim of this study was to evaluate whether different megakaryocytic progenitors from unseparated CBUs survive the freezing process and a short-term liquid culture. Thawed samples of CBUs were cultured in liquid medium. During the cultures, serial samples were drawn to assess the growth of different megakaryocytic progenitors in a semisolid collagen medium with identical cytokines as in the liquid medium. Megakaryocytic cells were detected using immunohistochemistry and flow cytometry. In suspension culture, the megakaryocytic progenitors almost completely lost the ability to generate large (burst-forming unit-like, BFU-like) megakaryocytic colonies in semisolid cultures (large colonies, median count per chamber d0: 7.25 vs. d7: 1.5; P culture in suspension resulted in the decline of small colonies as well (d7: 16.0 vs. d14: 5.75; P = 0.0088). Total CFU-Mk count declined from 23.3 (range 12.5-34.0) at d0 to 7.25 (range 1.0-13.5) at d14 (P culture after a short suspension culture. Small CFU-Mks were observed throughout the cultures. It may be that the BFU-Mk colonies matured and acquired CFU-Mk behaviour. © 2014 International Society of Blood Transfusion.

Increasing cell culture population doublings for long-term growth of finite life span human cell cultures

Science.gov (United States)

Stampfer, Martha R; Garbe, James C

2015-02-24

Cell culture media formulations for culturing human epithelial cells are herein described. Also described are methods of increasing population doublings in a cell culture of finite life span human epithelial cells and prolonging the life span of human cell cultures. Using the cell culture media disclosed alone and in combination with addition to the cell culture of a compound associated with anti-stress activity achieves extended growth of pre-stasis cells and increased population doublings and life span in human epithelial cell cultures.

Cell envelope stress response in cell wall-deficient L-forms of Bacillus subtilis.

Science.gov (United States)

Wolf, Diana; Domínguez-Cuevas, Patricia; Daniel, Richard A; Mascher, Thorsten

2012-11-01

L-forms are cell wall-deficient bacteria that can grow and proliferate in osmotically stabilizing media. Recently, a strain of the Gram-positive model bacterium Bacillus subtilis was constructed that allowed controlled switching between rod-shaped wild-type cells and corresponding L-forms. Both states can be stably maintained under suitable culture conditions. Because of the absence of a cell wall, L-forms are known to be insensitive to β-lactam antibiotics, but reports on the susceptibility of L-forms to other antibiotics that interfere with membrane-anchored steps of cell wall biosynthesis are sparse, conflicting, and strongly influenced by strain background and method of L-form generation. Here we investigated the response of B. subtilis to the presence of cell envelope antibiotics, with regard to both antibiotic resistance and the induction of the known LiaRS- and BceRS-dependent cell envelope stress biosensors. Our results show that B. subtilis L-forms are resistant to antibiotics that interfere with the bactoprenol cycle, such as bacitracin, vancomycin, and mersacidin, but are hypersensitive to nisin and daptomycin, which both affect membrane integrity. Moreover, we established a lacZ-based reporter gene assay for L-forms and provide evidence that LiaRS senses its inducers indirectly (damage sensing), while the Bce module detects its inducers directly (drug sensing).

Establishment of automated culture system for murine induced pluripotent stem cells

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Koike Hiroyuki

2012-11-01

Full Text Available Abstract Background Induced pluripotent stem (iPS cells can differentiate into any cell type, which makes them an attractive resource in fields such as regenerative medicine, drug screening, or in vitro toxicology. The most important prerequisite for these industrial applications is stable supply and uniform quality of iPS cells. Variation in quality largely results from differences in handling skills between operators in laboratories. To minimize these differences, establishment of an automated iPS cell culture system is necessary. Results We developed a standardized mouse iPS cell maintenance culture, using an automated cell culture system housed in a CO2 incubator commonly used in many laboratories. The iPS cells propagated in a chamber uniquely designed for automated culture and showed specific colony morphology, as for manual culture. A cell detachment device in the system passaged iPS cells automatically by dispersing colonies to single cells. In addition, iPS cells were passaged without any change in colony morphology or expression of undifferentiated stem cell markers during the 4 weeks of automated culture. Conclusions Our results show that use of this compact, automated cell culture system facilitates stable iPS cell culture without obvious effects on iPS cell pluripotency or colony-forming ability. The feasibility of iPS cell culture automation may greatly facilitate the use of this versatile cell source for a variety of biomedical applications.

The in vitro and in vivo capacity of culture-expanded human cells from several sources encapsulated in alginate to form cartilage

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MM Pleumeekers

2014-04-01

Full Text Available Cartilage has limited self-regenerative capacity. Tissue engineering can offer promising solutions for reconstruction of missing or damaged cartilage. A major challenge herein is to define an appropriate cell source that is capable of generating a stable and functional matrix. This study evaluated the performance of culture-expanded human chondrocytes from ear (EC, nose (NC and articular joint (AC, as well as bone-marrow-derived and adipose-tissue-derived mesenchymal stem cells both in vitro and in vivo. All cells (≥ 3 donors per source were culture-expanded, encapsulated in alginate and cultured for 5 weeks. Subsequently, constructs were implanted subcutaneously for 8 additional weeks. Before and after implantation, glycosaminoglycan (GAG and collagen content were measured using biochemical assays. Mechanical properties were determined using stress-strain-indentation tests. Hypertrophic differentiation was evaluated with qRT-PCR and subsequent endochondral ossification with histology. ACs had higher chondrogenic potential in vitro than the other cell sources, as assessed by gene expression and GAG content (p < 0.001. However, after implantation, ACs did not further increase their matrix. In contrast, ECs and NCs continued producing matrix in vivo leading to higher GAG content (p < 0.001 and elastic modulus. For NC-constructs, matrix-deposition was associated with the elastic modulus (R2 = 0.477, p = 0.039. Although all cells – except ACs – expressed markers for hypertrophic differentiation in vitro, there was no bone formed in vivo. Our work shows that cartilage formation and functionality depends on the cell source used. ACs possess the highest chondrogenic capacity in vitro, while ECs and NCs are most potent in vivo, making them attractive cell sources for cartilage repair.

Lipoprotein receptors in cultured bovine endothelial cells

International Nuclear Information System (INIS)

Struempfer, A.E.M.

1983-07-01

In this study, receptors that may be involved in the uptake of low density lipoproteins (LDL) and low density lipoproteins which have been modified by acetylation (AcLDL), were characterized. Aortic epithelial cells were used and a cell culture system which closely resembled the in vivo monolayer was established. Endothelial cell and lipoprotein interactions were examined by incubating the cells with 125 l-labelled lipoproteins under various conditions. The receptor affinity of bovine aortic endothelial cells was higher for AcLDL than that for LDL. Competition studies demonstrated that there were two distinct receptors for LDL and AcLDL on the endothelial cells. AcLDL did not compete with LDL for the LDL receptor, and conversely LDL did not compete with AcLDL for the AcLDL receptor. The receptor activities for LDL and AcLDL were examined as a function of culture age. Whereas the LDL receptor could be regulated, the AcLDL receptor was not as susceptible to regulation. Upon exposing endothelial cells for 72 h to either LDL or AcLDL, it was found that the total amount of cellular cholesterol increased by about 50%. However, the increase of total cholesterol was largely in the form of free cholesterol. This is in contrast to macrophages, where the increase in total cholesterol upon exposure to AcLDL is largely in the form cholesteryl esters

Photoreactivation of ultraviolet light-induced damage in cultured fish cells as revealed by increased colony forming ability and decreased content of pyrimidine dimers

International Nuclear Information System (INIS)

Shima, A.; Ikenaga, M.; Egami, N.

1981-01-01

Cultured cells derived from a goldfish were irradiated with 254 nm ultraviolet light. Cell survival and splitting of pyrimidine dimers after photoreactivation treatment with white fluorescent lamps were examined by colony forming ability and by a direct dimer assay, respectively. When UV-irradiated (5 J/m 2 ) cells were illuminated by photoreactivating light, cell survival was enhanced up to a factor of 9(40 min) followed by a decline after prolonged exposures. Exposure of UV-irradiated (15 J/m 2 ) cells to radiation from white fluorescent lamps reduced the amounts of thymine-containing dimers in a photoreactivating fluence dependent manner, up to about 60% reduction at 120 min exposure. Keeping UV-irradiated cells in the dark for up to 120 min did not affect either cell survival or the amount of pyrimidine dimers in DNA, indicating that there were not detectable levels of a dark-repair system in the cells under our conditions. Correlation between photoreactivation of colony forming ability and photoreactivation of the pyrimidine dimers was demonstrated, at least at relatively low fluences of photoreactivating light. (author)

Photoreactivation of ultraviolet light-induced damage in cultured fish cells as revealed by increased colony forming ability and decreased content of pyrimidine dimers

Energy Technology Data Exchange (ETDEWEB)

Shima, A. (Shiga University of Medical Science, Otsu (Japan)); Ikenaga, M. (Osaka Univ. (Japan). Faculty of Medicine); Nikaido, O.; Takebe, H. (Kyoto Univ. (Japan)); Egami, N. (Tokyo Univ. (Japan). Faculty of Science)

1981-03-01

Cultured cells derived from a goldfish were irradiated with 254 nm ultraviolet light. Cell survival and splitting of pyrimidine dimers after photoreactivation treatment with white fluorescent lamps were examined by colony forming ability and by a direct dimer assay, respectively. When UV-irradiated (5 J/m/sup 2/) cells were illuminated by photoreactivating light, cell survival was enhanced up to a factor of 9(40 min) followed by a decline after prolonged exposures. Exposure of UV-irradiated (15 J/m/sup 2/) cells to radiation from white fluorescent lamps reduced the amounts of thymine-containing dimers in a photoreactivating fluence dependent manner, up to about 60% reduction at 120 min exposure. Keeping UV-irradiated cells in the dark for up to 120 min did not affect either cell survival or the amount of pyrimidine dimers in DNA, indicating that there were not detectable levels of a dark-repair system in the cells under our conditions. Correlation between photoreactivation of colony forming ability and photoreactivation of the pyrimidine dimers was demonstrated, at least at relatively low fluences of photoreactivating light.

Emerging Forms of Cultural Capital

DEFF Research Database (Denmark)

Prieur, Annick; Savage, Mike

assessment of the arguments made, including those made in the studies we have been involved in ourselves (the study of cultural capital and social exclusion in the UK, and the study of the Danish city Aalborg). Secondly, the paper looks into the different claims that are made in empirical studies after...... - the claims that there are forms of emotional, subcultural or national cultural capital at work - The claim about cosmopolitanism or an international orientation as a distinctive feature of the culturally privileged classes The paper responds to the first theme announced in the call for this conference......This paper reviews recent European studies to assess whether cultural capital now has the same characteristics – or may be rather the same functions - as when Distinction was written. The paper will examine empirical applications of the concept of cultural capital in leading European studies...

Cultural forms of thinking as translation-communicative basis of the individual

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Chekrygina T. A.

2017-12-01

Full Text Available social psychology approach to cultural dynamics used by the authors formed within the framework of the cultural and historical concept is a comparative analysis of cultural-historical process that helps to identify its main characteristic features of a particular cultural community, which are the most sustainable socio-cultural entities (cultural forms and perform translation-communication function of the culture impact on personality development and social relations. The authors concluded that cultural forms were the main determinants of socio-cultural identification with internal mechanism – cultural forms of thinking

Differentiation of oligodendrocyte progenitor cells from dissociated monolayer and feeder-free cultured pluripotent stem cells.

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Yamashita, Tomoko; Miyamoto, Yuki; Bando, Yoshio; Ono, Takashi; Kobayashi, Sakurako; Doi, Ayano; Araki, Toshihiro; Kato, Yosuke; Shirakawa, Takayuki; Suzuki, Yutaka; Yamauchi, Junji; Yoshida, Shigetaka; Sato, Naoya

2017-01-01

Oligodendrocytes myelinate axons and form myelin sheaths in the central nervous system. The development of therapies for demyelinating diseases, including multiple sclerosis and leukodystrophies, is a challenge because the pathogenic mechanisms of disease remain poorly understood. Primate pluripotent stem cell-derived oligodendrocytes are expected to help elucidate the molecular pathogenesis of these diseases. Oligodendrocytes have been successfully differentiated from human pluripotent stem cells. However, it is challenging to prepare large amounts of oligodendrocytes over a short amount of time because of manipulation difficulties under conventional primate pluripotent stem cell culture methods. We developed a proprietary dissociated monolayer and feeder-free culture system to handle pluripotent stem cell cultures. Because the dissociated monolayer and feeder-free culture system improves the quality and growth of primate pluripotent stem cells, these cells could potentially be differentiated into any desired functional cells and consistently cultured in large-scale conditions. In the current study, oligodendrocyte progenitor cells and mature oligodendrocytes were generated within three months from monkey embryonic stem cells. The embryonic stem cell-derived oligodendrocytes exhibited in vitro myelinogenic potency with rat dorsal root ganglion neurons. Additionally, the transplanted oligodendrocyte progenitor cells differentiated into myelin basic protein-positive mature oligodendrocytes in the mouse corpus callosum. This preparative method was used for human induced pluripotent stem cells, which were also successfully differentiated into oligodendrocyte progenitor cells and mature oligodendrocytes that were capable of myelinating rat dorsal root ganglion neurons. Moreover, it was possible to freeze, thaw, and successfully re-culture the differentiating cells. These results showed that embryonic stem cells and human induced pluripotent stem cells maintained in a

Culture and Characterization of Circulating Endothelial Progenitor Cells in Patients with Renal Cell Carcinoma.

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Gu, Wenyu; Sun, Wei; Guo, Changcheng; Yan, Yang; Liu, Min; Yao, Xudong; Yang, Bin; Zheng, Junhua

2015-07-01

Although emerging evidence demonstrates increased circulating endothelial progenitor cells in patients with solid tumors, to our knowledge it is still unknown whether such cells can be cultured from patients with highly angiogenic renal cell carcinoma. We cultured and characterized circulating endothelial progenitor cells from patients with renal cell carcinoma. The circulating endothelial progenitor cell level (percent of CD45(-)CD34(+) VEGF-R2(+) cells in total peripheral blood mononuclear cells) was quantified in 47 patients with renal cell carcinoma and 40 healthy controls. Peripheral blood mononuclear cells were then isolated from 33 patients with renal cell carcinoma and 30 healthy controls to culture and characterize circulating endothelial progenitor cells. The circulating endothelial progenitor cell level was significantly higher in patients with renal cell carcinoma than in healthy controls (0.276% vs 0.086%, p cells first emerged significantly earlier in patient than in control preparations (6.72 vs 14.67 days, p culture success rate (87.8% vs 40.0% of participants) and the number of colonies (10.06 vs 1.83) were significantly greater for patients than for controls (each p cell level correlated positively with the number of patient colonies (r = 0.762, p Cells cultured from patients and controls showed a similar growth pattern, immunophenotype, ability to uptake Ac-LDL and bind lectin, and form capillary tubes in vitro. However, significantly more VEGF-R2(+) circulating endothelial progenitor cells were found in preparations from patients with renal cell carcinoma than from healthy controls (21.1% vs 13.4%, p cell colonies, a higher cell culture success rate and more colonies were found for patients with renal cell carcinoma than for healthy controls. Results indicate the important significance of VEGF-R2(+) circulating endothelial progenitors in patients with renal cell carcinoma. Copyright © 2015 American Urological Association Education and Research

Comparison of 864 and 935 MHz microwave radiation effects on cell culture

International Nuclear Information System (INIS)

Pavicic, I.; Trosic, I.; Sarolic, A.

2005-01-01

The aim of our study was to evaluate and compare the effect of 864 and 935 MHz microwave radiation on proliferation, colony forming and viability of Chinese hamster lung cells, cell line V79. Cell cultures were exposed both to the 864 MHz microwave field in transversal electromagnetic mode cell (TEM-cell) and to the 935 MHz field in Gigahertz transversal electromagnetic mode cell (GTEM-cell) for 1, 2 and 3 hours. Philips PM 5508 generator connected with a signal amplifier generated the frequency of 864 MHz, whereas Hewlett Packard HP8657A signal generator was used to generate the frequency of 935 MHz. The average specific absorption rate (SAR) was 0.08 W/kg for 864 MHz and 0.12 W/kg for 935 MHz. To determine the cell growth, V79 cells were plated in the concentration of 1x10 4 cells per milliliter of nutrient medium. Cells were cultured in a humidified atmosphere at 37 degrees of C in 5% CO 2 . Cell proliferation was determined by cell counts for each hour of exposure during the five post-exposure days. To identify colony-forming ability, cells were cultivated in the concentration of 40 cells/mL of medium and incubated as described above. Colony-forming ability was assessed for each exposure time by colony count on post-exposure day 7. Trypan blue exclusion test was used to determine cell viability. On post-exposure day 3, the growth curve of 864 MHz irradiated cells showed a significant decrease (p less than 0.05) after 2 and 3 hours of exposure in comparison with control cells. Cells exposed to 935 MHz radiation showed a significant decrease (p less than 0.05) after 3 hours of exposure on post-exposure day 3. Both the colony-forming ability and viability of 864 MHz and 935 MHz exposed cells did not significantly differ from matched control cells. In conclusion, both applied RF/MW fields have shown similar effects on cell culture growth, colony forming and cell viability of the V79 cell line.(author)

Structural relationships among the multiple forms of DNA-dependent RNA polymerase II from cultured parsley cells

International Nuclear Information System (INIS)

Link, G.; Bogorad, L.; Kidd, G.H.; Richter, G.

1978-01-01

DNA-dependent RNA polymerase II (or B) was purified from cultured parsley cells, and its molecular structure was examined in detail. Upon centrifugation through glycerol gradients, RNA polymerase II sediments as a single band with an apparent sedimentation constant of 15S. No contamination with RNA polymerases I or III could be detected when the activity of purified RNA polymerase II was assayed in the presence of high concentrations of α-amanitin. Analysis of purified RNA polymerase II be nondenaturing and denaturing polyacrylamide gel electrophoresis revealed that this enzyme exists in multiple forms. They were designated II(O), II(A), and II(B). It is suggested that each form has a subunit of Mr = 140000 as well as smaller polypeptides in common. They differ, however, in the molecular weights of their largest subunits which is 220000 in form II(O), 200000 in form II(A), and 180000 in form II(B). These large subunits were labelled with 125 I, digested with trypsin, and tryptic digests were compared by two-dimensional analysis on thin-layer plates (Elder et al. (1977) J. Biol. Chem. 252, 6510-6515). Fingerprints of tryptic digests from the polypeptides with Mr = 220000, Mr = 200000, and Mr = 180000 were similar. It is, therefore, suggested that these subunits are stucturally related. A tryptic digest was also produced from the subunit with Mr = 140000. Its fingerprint was found to yield a considerably different distribution of peptides as compared to those from the three large subunits. (orig.) [de

Decreased hypertrophic differentiation accompanies enhanced matrix formation in co-cultures of outer meniscus cells with bone marrow mesenchymal stromal cells

Science.gov (United States)

2012-01-01

Introduction The main objective of this study was to determine whether meniscus cells from the outer (MCO) and inner (MCI) regions of the meniscus interact similarly to or differently with mesenchymal stromal stem cells (MSCs). Previous study had shown that co-culture of meniscus cells with bone marrow-derived MSCs result in enhanced matrix formation relative to mono-cultures of meniscus cells and MSCs. However, the study did not examine if cells from the different regions of the meniscus interacted similarly to or differently with MSCs. Methods Human menisci were harvested from four patients undergoing total knee replacements. Tissue from the outer and inner regions represented pieces taken from one third and two thirds of the radial distance of the meniscus, respectively. Meniscus cells were released from the menisci after collagenase treatment. Bone marrow MSCs were obtained from the iliac crest of two patients after plastic adherence and in vitro culture until passage 2. Primary meniscus cells from the outer (MCO) or inner (MCI) regions of the meniscus were co-cultured with MSCs in three-dimensional (3D) pellet cultures at 1:3 ratio, respectively, for 3 weeks in the presence of serum-free chondrogenic medium containing TGF-β1. Mono-cultures of MCO, MCI and MSCs served as experimental control groups. The tissue formed after 3 weeks was assessed biochemically, histochemically and by quantitative RT-PCR. Results Co-culture of inner (MCI) or outer (MCO) meniscus cells with MSCs resulted in neo-tissue with increased (up to 2.2-fold) proteoglycan (GAG) matrix content relative to tissues formed from mono-cultures of MSCs, MCI and MCO. Co-cultures of MCI or MCO with MSCs produced the same amount of matrix in the tissue formed. However, the expression level of aggrecan was highest in mono-cultures of MSCs but similar in the other four groups. The DNA content of the tissues from co-cultured cells was not statistically different from tissues formed from mono-cultures of

Evaluation of a dental pulp-derived cell sheet cultured on amniotic membrane substrate.

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Honjo, Ken-ichi; Yamamoto, Toshiro; Adachi, Tetsuya; Amemiya, Takeshi; Mazda, Osam; Kanamura, Narisato; Kita, Masakazu

2015-01-01

Mesenchymal stem cells (MSC) are transplanted for periodontal tissue regeneration, and the periodontal ligament (PDL) is regenerated using a cultured cell sheet. This cultured cell sheet is prepared using PDL-derived cells, growth factors, and amniotic membrane (AM). Dental pulp (DP)-derived cells can be easily obtained from extracted wisdom teeth, proliferate rapidly, and are less susceptible to bacterial infection than PDL-derived cells. Thus, to prepare a novel cell sheet, DP-derived cells were cultured on AM as a culture substrate for immunohistochemical examination. Wisdom teeth extracted from three adults were cut along the cement-enamel border. DP tissue was collected, minced, and primarily cultured. After three or four passage cultures, DP-derived cells were cultured on AM, followed by hematoxylin-eosin (H-E) and immunofluorescence staining. DP-derived cells cultured on AM formed a layered structure. Cells positive for vimentin, Ki-67, ZO-1, desmoplakin, CD29, 44, 105 or 146, STRO-1, collagen IV or VII or laminin 5 or α5 chain were localized. DP-derived cells proliferated on AM, while retaining the properties of DP, which allowed the cultured cell sheet to be prepared. In addition, the cultured cell sheet contained MSC, which suggests its potential application in periodontal tissue regeneration.

Long-term Culture of Human iPS Cell-derived Telencephalic Neuron Aggregates on Collagen Gel.

Science.gov (United States)

Oyama, Hiroshi; Takahashi, Koji; Tanaka, Yoshikazu; Takemoto, Hiroshi; Haga, Hisashi

2018-01-01

It takes several months to form the 3-dimensional morphology of the human embryonic brain. Therefore, establishing a long-term culture method for neuronal tissues derived from human induced pluripotent stem (iPS) cells is very important for studying human brain development. However, it is difficult to keep primary neurons alive for more than 3 weeks in culture. Moreover, long-term adherent culture to maintain the morphology of telencephalic neuron aggregates induced from human iPS cells is also difficult. Although collagen gel has been widely used to support long-term culture of cells, it is not clear whether human iPS cell-derived neuron aggregates can be cultured for long periods on this substrate. In the present study, we differentiated human iPS cells to telencephalic neuron aggregates and examined long-term culture of these aggregates on collagen gel. The results indicated that these aggregates could be cultured for over 3 months by adhering tightly onto collagen gel. Furthermore, telencephalic neuronal precursors within these aggregates matured over time and formed layered structures. Thus, long-term culture of telencephalic neuron aggregates derived from human iPS cells on collagen gel would be useful for studying human cerebral cortex development.Key words: Induced pluripotent stem cell, forebrain neuron, collagen gel, long-term culture.

Theoretical Discussion on Forms of Cultural Capital in Singapore

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Tan, Cheng Yong

2013-01-01

This article is a theoretical discussion on five forms of cultural resources that constitute cultural capital for children in the meritocratic yet stratified society of Singapore. These five forms of cultural capital are namely "academic" tastes and leisure preferences, use of Standard English, access to and dispositions toward…

Trypanosoma cruzi. Surface antigens of blood and culture forms

International Nuclear Information System (INIS)

Nogueira, N.; Chaplan, S.; Tydings, J.D.; Unkeless, J.; Cohn, Z.

1981-01-01

The surface polypeptides of both cultured and blood forms of Trypanosoma cruzi were iodinated by the glucose oxidase-lactoperoxidase technique. Blood-form trypomastigotes (BFT) isolated form infected mice displayed a major 90,000-Mr component. In contrast, both epimastigotes and trypomastigotes obtained form acellular cultures expressed a smaller 75,000-Mr peptide. Both major surface components were presumably glycoproteins in terms of their binding to concanavalin A-Sepharose 4B. Within a 3-h period, both blood and culture forms synthesized their respective surface glycoproteins (90,000 Mr and 75,000 Mr, respectively in vitro. [/sub 35/S]methionine-labeled surface peptides were immunoprecipitated with immune sera of both human and murine origin. A panel of sera form patients with chronic Chagas' disease and hyperimmunized mice recognized similar surface peptides. These immunogens were the same components as the major iodinated species. The major BFT surface peptide was readily removed by trypsin treatment of the parasites, although the procedure did not affect the 75,000-Mr peptide from the culture forms. Two-dimensional polyacrylamide gel electrophoresis revealed that the 90,000-Mr peptide found on BFT was an acidic protein of isoelectric point (pI) 5.0, whereas, the 75,000-Mr peptide form culture-form trypomastigotes has a pI of 7.2. The 90,000-Mr component is thought to be responsible for the anti-phagocytic properties of the BFT

Induced pluripotent stem cell-derived cardiac progenitors differentiate to cardiomyocytes and form biosynthetic tissues.

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Nicolas Christoforou

Full Text Available The mammalian heart has little capacity to regenerate, and following injury the myocardium is replaced by non-contractile scar tissue. Consequently, increased wall stress and workload on the remaining myocardium leads to chamber dilation, dysfunction, and heart failure. Cell-based therapy with an autologous, epigenetically reprogrammed, and cardiac-committed progenitor cell source could potentially reverse this process by replacing the damaged myocardium with functional tissue. However, it is unclear whether cardiac progenitor cell-derived cardiomyocytes are capable of attaining levels of structural and functional maturity comparable to that of terminally-fated cardiomyocytes. Here, we first describe the derivation of mouse induced pluripotent stem (iPS cells, which once differentiated allow for the enrichment of Nkx2-5(+ cardiac progenitors, and the cardiomyocyte-specific expression of the red fluorescent protein. We show that the cardiac progenitors are multipotent and capable of differentiating into endothelial cells, smooth muscle cells and cardiomyocytes. Moreover, cardiac progenitor selection corresponds to cKit(+ cell enrichment, while cardiomyocyte cell-lineage commitment is concomitant with dual expression of either cKit/Flk1 or cKit/Sca-1. We proceed to show that the cardiac progenitor-derived cardiomyocytes are capable of forming electrically and mechanically coupled large-scale 2D cell cultures with mature electrophysiological properties. Finally, we examine the cell progenitors' ability to form electromechanically coherent macroscopic tissues, using a physiologically relevant 3D culture model and demonstrate that following long-term culture the cardiomyocytes align, and form robust electromechanical connections throughout the volume of the biosynthetic tissue construct. We conclude that the iPS cell-derived cardiac progenitors are a robust cell source for tissue engineering applications and a 3D culture platform for pharmacological

Identification of a population of cells with hematopoietic stem cell properties in mouse aorta-gonad-mesonephros cultures

International Nuclear Information System (INIS)

Nobuhisa, Ikuo; Ohtsu, Naoki; Okada, Seiji; Nakagata, Naomi; Taga, Tetsuya

2007-01-01

The aorta-gonad-mesonephros (AGM) region is a primary source of definitive hematopoietic cells in the midgestation mouse embryo. In cultures of dispersed AGM regions, adherent cells containing endothelial cells are observed first, and then non-adherent hematopoietic cells are produced. Here we report on the characterization of hematopoietic cells that emerge in the AGM culture. Based on the expression profiles of CD45 and c-Kit, we defined three cell populations: CD45 low c-Kit + cells that had the ability to form hematopoietic cell colonies in methylcellulose media and in co-cultures with stromal cells; CD45 low c-Kit - cells that showed a granulocyte morphology; CD45 high c-Kit low/- that exhibited a macrophage morphology. In co-cultures of OP9 stromal cells and freshly prepared AGM cultures, CD45 low c-Kit + cells from the AGM culture had the abilities to reproduce CD45 low c-Kit + cells and differentiate into CD45 low c-Kit - and CD45 high c-Kit low/- cells, whereas CD45 low c-Kit - and CD45 high c-Kit low/- did not produce CD45 low c-Kit + cells. Furthermore, CD45 low c-Kit + cells displayed a long-term repopulating activity in adult hematopoietic tissue when transplanted into the liver of irradiated newborn mice. These results indicate that CD45 low c-Kit + cells from the AGM culture have the potential to reconstitute multi-lineage hematopoietic cells

Antitumor Activity of Rat Mesenchymal Stem Cells during Direct or Indirect Co-Culturing with C6 Glioma Cells.

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Gabashvili, A N; Baklaushev, V P; Grinenko, N F; Mel'nikov, P A; Cherepanov, S A; Levinsky, A B; Chehonin, V P

2016-02-01

The tumor-suppressive effect of rat mesenchymal stem cells against low-differentiated rat C6 glioma cells during their direct and indirect co-culturing and during culturing of C6 glioma cells in the medium conditioned by mesenchymal stem cells was studied in an in vitro experiment. The most pronounced antitumor activity of mesenchymal stem cells was observed during direct co-culturing with C6 glioma cells. The number of live C6 glioma cells during indirect co-culturing and during culturing in conditioned medium was slightly higher than during direct co-culturing, but significantly differed from the control (C6 glioma cells cultured in medium conditioned by C6 glioma cells). The cytotoxic effect of medium conditioned by mesenchymal stem cells was not related to medium depletion by glioma cells during their growth. The medium conditioned by other "non-stem" cells (rat astrocytes and fibroblasts) produced no tumor-suppressive effect. Rat mesenchymal stem cells, similar to rat C6 glioma cells express connexin 43, the main astroglial gap junction protein. During co-culturing, mesenchymal stem cells and glioma C6 cells formed functionally active gap junctions. Gap junction blockade with connexon inhibitor carbenoxolone attenuated the antitumor effect observed during direct co-culturing of C6 glioma cells and mesenchymal stem cells to the level produced by conditioned medium. Cell-cell signaling mediated by gap junctions can be a mechanism of the tumor-suppressive effect of mesenchymal stem cells against C6 glioma cells. This phenomenon can be used for the development of new methods of cell therapy for high-grade malignant gliomas.

Community Psychology, Diversity, and the Many Forms of Culture

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Tebes, Jacob Kraemer

2010-01-01

Comments on the original article, "Many forms of culture," by A. B. Cohen. Cohen argued that psychology must broaden its conceptualization of culture to consider its many forms, such as religion, socioeconomic status, and region. The current author could not agree more with Cohen's proposed conceptualization of culture and its potential impact on…

Octanoate in Human Albumin Preparations Is Detrimental to Mesenchymal Stromal Cell Culture

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Way-Wua Wong

2015-01-01

Full Text Available Cell therapies hold great promise as the next major advance in medical treatment. To enable safe, effective ex vivo culture whilst maintaining cell phenotype, growth media constituents must be carefully controlled. We have used a chemically defined mesenchymal stromal cell culture medium to investigate the influence of different preparations of human serum albumin. We examined two aspects of cell culture, growth rate as measured by population doubling time and colony forming ability which is a representative measure of the stemness of the cell population. Albumin preparations showed comparative differences in both of these criteria. Analysis of the albumin bound fatty acids also showed differences depending on the manufacturing procedure used. We demonstrated that octanoate, an additive used to stabilize albumin during pasteurization, slows growth and lowers colony forming ability during ex vivo culture. Further to this we also found the level of Na+/K+ ATPase, a membrane bound cation pump inhibited by octanoate, is increased in cells exposed to this compound. We conclude that the inclusion of human serum albumin in ex vivo growth media requires careful consideration of not only the source of albumin, but also the associated molecular cargo, for optimal cell growth and behavior.

Metabolic labeling with (14C)-glucose of bloodstream and cell culture trypanosoma cruzi trypomastigotes:

International Nuclear Information System (INIS)

Lederkremer, R.M. de; Groisman, J.F.; Lima, C.; Katzin, A.

1990-01-01

Trypomastigote forms of Trypanosoma cruzi from infected mouse blood and from cell culture were metabolically labeled by incubation with D-( 14 C)-glucose. Analysis by polyacrylamide gel electrophoresis of lysates from parasites of two strains (RA and CA 1 ) showed a significantly different pattern. The difference was mainly quantitative when the blood and cell culture trypomastigotes of the RA strain were compared. Analysis of the culture medium by paper electrophoresis showed an anionic exometabolite only in the blood forms of both strains. (Author) [es

Reassembly of anterior pituitary organization by hanging drop three-dimensional cell culture.

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Tsukada, Takehiro; Kouki, Tom; Fujiwara, Ken; Ramadhani, Dini; Horiguchi, Kotaro; Kikuchi, Motoshi; Yashiro, Takashi

2013-08-29

The anterior pituitary gland comprises 5 types of hormone-producing cells and non-endocrine cells, such as folliculostellate (FS) cells. The cells form a lobular structure surrounded by extracellular matrix (ECM) but are not randomly distributed in each lobule; hormone-producing cells have affinities for specific cell types (topographic affinity), and FS cells form a homotypic meshwork. To determine whether this cell and ECM organization can be reproduced in vitro, we developed a 3-dimensional (3D) model that utilizes hanging drop cell culture. We found that the topographic affinities of hormone-producing cells were indeed maintained (ie, GH to ACTH cells, GH to TSH cells, PRL to LH/FSH cells). Fine structures in hormone-producing cells retained their normal appearance. In addition, FS cells displayed well-developed cytoplasmic protrusions, which interconnected with adjacent FS cells to form a 3D meshwork. In addition, reassembly of gap junctions and pseudofollicles among FS cells was observed in cell aggregates. Major ECM components-collagens and laminin-were deposited and distributed around the cells. In sum, the dissociated anterior pituitary cells largely maintained their in vivo anterior pituitary architectures. This culture system appears to be a powerful experimental tool for detailed analysis of anterior pituitary cell organization.

The interaction of hepatitis A virus (HAV with soluble forms of its cellular receptor 1 (HAVCR1 share the physiological requirements of infectivity in cell culture

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Kaplan Gerardo G

2009-10-01

Full Text Available Abstract Background Hepatitis A virus (HAV, an atypical Picornaviridae that causes acute hepatitis in humans, usurps the HAV cellular receptor 1 (HAVCR1 to infect cells. HAVCR1 is a class 1 integral membrane glycoprotein that contains two extracellular domains: a virus-binding immunoglobulin-like (IgV domain and a mucin-like domain that extends the IgV from the cell membrane. Soluble forms of HAVCR1 bind, alter, and neutralize cell culture-adapted HAV, which is attenuated for humans. However, the requirements of the HAV-HAVCR1 interaction have not been fully characterized, and it has not been determined whether HAVCR1 also serves as a receptor for wild-type (wt HAV. Here, we used HAV soluble receptor neutralization and alteration assays to study the requirements of the HAV-HAVCR1 interaction and to determine whether HAVCR1 is also a receptor for wt HAV. Results Treatment of HAV with a soluble form of HAVCR1 that contained the IgV and two-thirds of the mucin domain fused to the Fc fragment of human IgG1 (D1 muc-Fc, altered particles at 37°C but left a residual level of unaltered particles at 4°C. The kinetics of neutralization of HAV by D1 muc-Fc was faster at 37°C than at 4°C. Alteration of HAV particles by D1 muc-Fc required Ca, which could not be replaced by Li, Na, Mg, Mn, or Zn. Neutralization of HAV by D1 muc-Fc occurred at pH 5 to 8 but was more efficient at pH 6 to 7. D1 muc-Fc neutralized wt HAV as determined by a cell culture system that allows the growth of wt HAV. Conclusion The interaction of HAV with soluble forms of HAVCR1 shares the temperature, Ca, and pH requirements for infectivity in cell culture and therefore mimics the cell entry process of HAV. Since soluble forms of HAVCR1 also neutralized wt HAV, this receptor may play a significant role in pathogenesis of HAV.

An efficient 3D cell culture method on biomimetic nanostructured grids.

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Maria Wolun-Cholewa

Full Text Available Current techniques of in vitro cell cultures are able to mimic the in vivo environment only to a limited extent, as they enable cells to grow only in two dimensions. Therefore cell culture approaches should rely on scaffolds that provide support comparable to the extracellular matrix. Here we demonstrate the advantages of novel nanostructured three-dimensional grids fabricated using electro-spinning technique, as scaffolds for cultures of neoplastic cells. The results of the study show that the fibers allow for a dynamic growth of HeLa cells, which form multi-layer structures of symmetrical and spherical character. This indicates that the applied scaffolds are nontoxic and allow proper flow of oxygen, nutrients, and growth factors. In addition, grids have been proven to be useful in in situ examination of cells ultrastructure.

Hepatitis B surface antigen (HBsAg) expression in plant cell culture: Kinetics of antigen accumulation in batch culture and its intracellular form.

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Smith, Mark L; Mason, Hugh S; Shuler, Michael L

2002-12-30

The production of edible vaccines in transgenic plants and plant cell culture may be improved through a better understanding of antigen processing and assembly. The hepatitis B surface antigen (HBsAg) was chosen for study because it undergoes substantial and complex post-translational modifications, which are necessary for its immunogenicity. This antigen was expressed in soybean (Glycine max L. Merr. cv Williams 82) and tobacco NT1 (Nicotiana tabacum L.) cell suspension cultures, and HBsAg production in batch culture was characterized. The plant-derived antigen consisted predominantly of disulfide cross-linked HBsAg protein (p24(s)) dimers, which were all membrane associated. Similar to yeast, the plant-expressed HBsAg was retained intracellularly. The maximal HBsAg titers were obtained with soybean suspension cultures (20-22 mg/L) with titers in tobacco cultures being approximately 10-fold lower. For soybean cells, electron microscopy and immunolocalization demonstrated that all the HBsAg was localized to the endoplasmic reticulum (ER) and provoked dilation and proliferation of the ER network. Sucrose gradient analysis of crude extracts showed that HBsAg had a complex size distribution uncharacteristic of the antigen's normal structure of uniform 22-nm virus-like particles. The extent of authentic epitope formation was assessed by comparing total p24(s) synthesized to that reactive by polyclonal and monoclonal immunoassays. Depending on culture age, between 40% and 100% of total p24(s) was polyclonal antibody reactive whereas between 6% and 37% was recognized by a commercial monoclonal antibody assay. Possible strategies to increase HBsAg production and improve post-translational processing are discussed. Copyright 2002 Wiley Periodicals, Inc.

Cell in situ zymography: an in vitro cytotechnology for localization of enzyme activity in cell culture.

Science.gov (United States)

Chhabra, Aastha; Jaiswal, Astha; Malhotra, Umang; Kohli, Shrey; Rani, Vibha

2012-09-01

In situ zymography is a unique technique for detection and localization of enzyme-substrate interactions majorly in histological sections. Substrate with quenched fluorogenic molecule is incorporated in gel over which tissue sections are mounted and then incubated in buffer. The enzymatic activity is observed in the form of fluorescent signal. With the advancements in the field of biological research, use of in vitro cell culture has become very popular and holds great significance in multiple fields including inflammation, cancer, stem cell biology and the still emerging 3-D cell cultures. The information on analysis of enzymatic activity in cell lines is inadequate presently. We propose a single-step methodology that is simple, sensitive, cost-effective, and functional to perform and study the 'in position' activity of enzyme on substrate for in vitro cell cultures. Quantification of enzymatic activity to carry out comparative studies on cells has also been illustrated. This technique can be applied to a variety of enzyme classes including proteases, amylases, xylanases, and cellulases in cell cultures.

Nacre formation by epithelial cell cultures from mantle of the black-lip pearl oyster, Pinctada margaritifera.

Science.gov (United States)

Jayasankar, Vidya; Vasudevan, Srinivasa Raghavan; Poulose, Suja C; Divipala, Indira

2018-06-12

Mantle tissue from the black-lip pearl oyster, Pinctada margaritifera, was cultured in vitro using sterilized seawater supplemented with 0.1% yeast extract as the culture medium. Granular and agranular epithelial cells, hyalinocytes, and fibroblast-like cells were observed in the initial stages of culture. Epithelial cells later formed pseudopodial cell networks containing clusters of granulated cells, which upon maturation released their colored granules. These granules induced formation of nacre crystal deposits on the bottom of the culture plate. Cultures comprised of only granulated epithelial cells were established through periodic sub-culturing of mantle cells and maintained for over 18 mo in a viable condition. Reverse transcriptase PCR of cultured cells demonstrated gene expression of the shell matrix protein, nacrein. To further evaluate the functional ability of cultured granulated epithelial cells, nuclear shell beads were incubated in culture medium containing these cells to induce nacre formation on the beads. Observation of the bead surface under a stereomicroscope at periodic intervals showed the gradual formation of blackish yellow colored nacre deposits. Examination of the bead surface by scanning electron microscopy and energy dispersive X-ray analysis at periodic intervals revealed a distinct brick and mortar formation characteristic of nacre, comprised of aragonite platelets and matrix proteins. Calcium, carbon, and oxygen were the major elements in all stages examined. Our study shows that mantle epithelial cells in culture retain the ability to secrete nacre and can therefore form the basis for future studies on the biomineralization process and its application in development of sustainable pearl culture.

Perfusion based cell culture chips

DEFF Research Database (Denmark)

Heiskanen, Arto; Emnéus, Jenny; Dufva, Martin

2010-01-01

Performing cell culture in miniaturized perfusion chambers gives possibilities to experiment with cells under near in vivo like conditions. In contrast to traditional batch cultures, miniaturized perfusion systems provide precise control of medium composition, long term unattended cultures...... and tissue like structuring of the cultures. However, as this chapter illustrates, many issues remain to be identified regarding perfusion cell culture such as design, material choice and how to use these systems before they will be widespread amongst biomedical researchers....

Electrospinning PCL Scaffolds Manufacture for Three-Dimensional Breast Cancer Cell Culture

Directory of Open Access Journals (Sweden)

Marc Rabionet

2017-08-01

Full Text Available In vitro cell culture is traditionally performed within two-dimensional (2D environments, providing a quick and cheap way to study cell properties in a laboratory. However, 2D systems differ from the in vivo environment and may not mimic the physiological cell behavior realistically. For instance, 2D culture models are thought to induce cancer stem cells (CSCs differentiation, a rare cancer cell subpopulation responsible for tumor initiation and relapse. This fact hinders the development of therapeutic strategies for tumors with a high relapse percentage, such as triple negative breast cancer (TNBC. Thus, three-dimensional (3D scaffolds have emerged as an attractive alternative to monolayer culture, simulating the extracellular matrix structure and maintaining the differentiation state of cells. In this work, scaffolds were fabricated through electrospinning different poly(ε-caprolactone-acetone solutions. Poly(ε-caprolactone (PCL meshes were seeded with triple negative breast cancer (TNBC cells and 15% PCL scaffolds displayed significantly (p < 0.05 higher cell proliferation and elongation than the other culture systems. Moreover, cells cultured on PCL scaffolds exhibited higher mammosphere forming capacity and aldehyde dehydrogenase activity than 2D-cultured cells, indicating a breast CSCs enrichment. These results prove the powerful capability of electrospinning technology in terms of poly(ε-caprolactone nanofibers fabrication. In addition, this study has demonstrated that electrospun 15% PCL scaffolds are suitable tools to culture breast cancer cells in a more physiological way and to expand the niche of breast CSCs. In conclusion, three-dimensional cell culture using PCL scaffolds could be useful to study cancer stem cell behavior and may also trigger the development of new specific targets against such malignant subpopulation.

Endothelial cells stimulate growth of normal and cancerous breast epithelial cells in 3D culture

Directory of Open Access Journals (Sweden)

Magnusson Magnus K

2010-07-01

Full Text Available Abstract Background Epithelial-stromal interaction provides regulatory signals that maintain correct histoarchitecture and homeostasis in the normal breast and facilitates tumor progression in breast cancer. However, research on the regulatory role of the endothelial component in the normal and malignant breast gland has largely been neglected. The aim of the study was to investigate the effects of endothelial cells on growth and differentiation of human breast epithelial cells in a three-dimensional (3D co-culture assay. Methods Breast luminal and myoepithelial cells and endothelial cells were isolated from reduction mammoplasties. Primary cells and established normal and malignant breast cell lines were embedded in reconstituted basement membrane in direct co-culture with endothelial cells and by separation of Transwell filters. Morphogenic and phenotypic profiles of co-cultures was evaluated by phase contrast microscopy, immunostaining and confocal microscopy. Results In co-culture, endothelial cells stimulate proliferation of both luminal- and myoepithelial cells. Furthermore, endothelial cells induce a subpopulation of luminal epithelial cells to form large acini/ducts with a large and clear lumen. Endothelial cells also stimulate growth and cloning efficiency of normal and malignant breast epithelial cell lines. Transwell and gradient co-culture studies show that endothelial derived effects are mediated - at least partially - by soluble factors. Conclusion Breast endothelial cells - beside their role in transporting nutrients and oxygen to tissues - are vital component of the epithelial microenvironment in the breast and provide proliferative signals to the normal and malignant breast epithelium. These growth promoting effects of endothelial cells should be taken into consideration in breast cancer biology.

Cloning higher plants from aseptically cultured tissues and cells

Science.gov (United States)

Krikorian, A. D.

1982-01-01

A review of aseptic culture methods for higher plants is presented, which focuses on the existing problems that limit or prevent the full realization of cloning plants from free cells. It is shown that substantial progress in clonal multiplication has been made with explanted stem tips or lateral buds which can be stimulated to produce numerous precocious axillary branches. These branches can then be separated or subdivided and induced to root in order to yield populations of genetically and phenotypically uniorm plantlets. Similarly, undifferentiated calluses can sometimes be induced to form shoots and/or roots adventitiously. Although the cell culture techniques required to produce somatic embryos are presently rudimentary, steady advances are being made in learning how to stimulate formation of somatic or adventive embryos from totipotent cells grown in suspension cultures. It is concluded that many problems exist in the producing and growing of totipotent or morphogenetically competent cell suspensions, but the potential benefits are great.

Hypoxic contraction of cultured pulmonary vascular smooth muscle cells

International Nuclear Information System (INIS)

Murray, T.R.; Chen, L.; Marshall, B.E.; Macarak, E.J.

1990-01-01

The cellular events involved in generating the hypoxic pulmonary vasoconstriction response are not clearly understood, in part because of the multitude of factors that alter pulmonary vascular tone. The goal of the present studies was to determine if a cell culture preparation containing vascular smooth muscle (VSM) cells could be made to contract when exposed to a hypoxic atmosphere. Cultures containing only fetal bovine pulmonary artery VSM cells were assessed for contractile responses to hypoxic stimuli by two methods. In the first, tension forces generated by cells grown on a flexible growth surface (polymerized polydimethyl siloxane) were manifested as wrinkles and distortions of the surface under the cells. Wrinkling of the surface was noted to progressively increase with time as the culture medium bathing the cells was made hypoxic (PO2 approximately 25 mmHg). The changes were sometimes reversible upon return to normoxic conditions and appeared to be enhanced in cells already exhibiting evidence of some baseline tone. Repeated passage in culture did not diminish the hypoxic response. Evidence for contractile responses to hypoxia was also obtained from measurements of myosin light chain (MLC) phosphorylation. Conversion of MLC to the phosphorylated species is an early step in the activation of smooth muscle contraction. Lowering the PO2 in the culture medium to 59 mmHg caused a 45% increase in the proportion of MLC in the phosphorylated form as determined by two-dimensional gel electrophoresis. Similarly, cultures preincubated for 4 h with 32P and then exposed to normoxia or hypoxia for a 5-min experimental period showed more than twice as much of the label in MLCs of the hypoxic cells

Cell death in Tetrahymena thermophila: new observations on culture conditions.

Science.gov (United States)

Christensen, S T; Sørensen, H; Beyer, N H; Kristiansen, K; Rasmussen, L; Rasmussen, M I

2001-01-01

We previously suggested that the cell fate of the protozoan ciliate, Tetrahymena thermophila, effectively relates to a quorum-sensing mechanism where cell-released factors support cell survival and proliferation. The cells have to be present above a critical initial density in a chemically defined nutrient medium in order to release a sufficient level of these factors to allow a new colony to flourish. At a relatively high rate of metabolism and/or macromolecular synthesis and below this critical density, cells began to die abruptly within 30 min of inoculation, and this death took the form of an explosive disintegration lasting less than 50 milliseconds. The cells died at any location in the culture, and the frequency of cell death was always lower in well-filled vials than those with medium/air interface. Cell death was inhibited by the addition of Actinomycin D or through modifications of the culture conditions either by reducing the oxygen tension or by decreasing the temperature of the growth medium. In addition, plastic caps in well-filled vials release substances, which promote cell survival. The fate of low-density cultures is related to certain 'physical' conditions, in addition to the availability of oxygen within closed culture systems. Copyright 2001 Academic Press.

Cell Culture Made Easy.

Science.gov (United States)

Dye, Frank J.

1985-01-01

Outlines steps to generate cell samples for observation and experimentation. The procedures (which use ordinary laboratory equipment) will establish a short-term primary culture of normal mammalian cells. Information on culture vessels and cell division and a list of questions to generate student interest and involvement in the topics are…

Breast Cancer Stem Cell Culture and Enrichment Using Poly(ε-Caprolactone Scaffolds

Directory of Open Access Journals (Sweden)

Sònia Palomeras

2016-04-01

Full Text Available The cancer stem cell (CSC population displays self-renewal capabilities, resistance to conventional therapies, and a tendency to post-treatment recurrence. Increasing knowledge about CSCs’ phenotype and functions is needed to investigate new therapeutic strategies against the CSC population. Here, poly(ε-caprolactone (PCL, a biocompatible polymer free of toxic dye, has been used to fabricate scaffolds, solid structures suitable for 3D cancer cell culture. It has been reported that scaffold cell culture enhances the CSCs population. A RepRap BCN3D+ printer and 3 mm PCL wire were used to fabricate circular scaffolds. PCL design and fabrication parameters were first determined and then optimized considering several measurable variables of the resulting scaffolds. MCF7 breast carcinoma cell line was used to assess scaffolds adequacy for 3D cell culture. To evaluate CSC enrichment, the Mammosphere Forming Index (MFI was performed in 2D and 3D MCF7 cultures. Results showed that the 60° scaffolds were more suitable for 3D culture than the 45° and 90° ones. Moreover, 3D culture experiments, in adherent and non-adherent conditions, showed a significant increase in MFI compared to 2D cultures (control. Thus, 3D cell culture with PCL scaffolds could be useful to improve cancer cell culture and enrich the CSCs population.

Metabolism of fluoranthene in different plant cell cultures and intact plants

Energy Technology Data Exchange (ETDEWEB)

Kolb, M.; Harms, H.

2000-05-01

The metabolism of fluoranthene was investigated in 11 cell cultures of different plant species using a [{sup 14}C]-labeled standard. Most species metabolized less than 5% of fluoranthene to soluble metabolites and formed less than 5% nonextractable residues during the standardized 48-h test procedure. Higher metabolic rates were observed in lettuce (Lactuca sativa, 6%), wheat (Tricitum aestivum, 9%), and tomato (Lycopersicon esculentum, 15%). A special high metabolic rate of nearly 50% was determined for the rose species Paul's Scarlet. Chromatographic analysis of metabolites extracted from aseptically grown tomato plants proved that the metabolites detected in the cell cultures were also formed in the intact plants. Metabolites produced in tomato and rose cells from [{sup 14}C]-fluoranthene were conjugated with glucose, glucuronic acid, and other cell components. After acid hydrolyses, the main metabolite of both species was 1-hydroxyfluoranthene as identified by gas chromatography-mass spectrometry and high-performance liquid chromatography with diode array detection. The second metabolite formed by both species was 8-hydroxyfluoranthene. A third metabolite in tomatoes was 3-hydroxyfluoranthene.

Single-cell printing to form three-dimensional lines of olfactory ensheathing cells

International Nuclear Information System (INIS)

Othon, Christina M; Ringeisen, Bradley R; Wu Xingjia; Anders, Juanita J

2008-01-01

Biological laser printing (BioLP(TM)) is a unique tool capable of printing high resolution two- and three-dimensional patterns of living mammalian cells, with greater than 95% viability. These results have been extended to primary cultured olfactory ensheathing cells (OECs), harvested from adult Sprague-Dawley rats. OECs have been found to provide stimulating environments for neurite outgrowth in spinal cord injury models. BioLP is unique in that small load volumes (∼μLs) are required to achieve printing, enabling low numbers of OECs to be harvested, concentrated and printed. BioLP was used to form several 8 mm lines of OECs throughout a multilayer hydrogel scaffold. The line width was as low as 20 μm, with most lines comprising aligned single cells. Fluorescent confocal microscopy was used to determine the functionality of the printed OECs, to monitor interactions between printed OECs, and to determine the extent of cell migration throughout the 3D scaffold. High-resolution printing of low cell count, harvested OECs is an important advancement for in vitro study of cell interactions and functionality. In addition, these cell-printed scaffolds may provide an alternative for spinal cord repair studies, as the single-cell patterns formed here are on relevant size scales for neurite outgrowth

A biocompatible micro cell culture chamber (mu CCC) for the culturing and on-line monitoring of eukaryote cells

DEFF Research Database (Denmark)

Stangegaard, Michael; Petronis, Sarunas; Jørgensen, Anders Michael

2006-01-01

culture chip compared to cell culture flasks. The cell culture chip could without further modification support cell growth of two other cell lines. Light coming from the microscope lamp during optical recordings of the cells was the only external factor identified, that could have a negative effect...... on cell survival. Low grade light exposure was however compatible with optical recordings as well as cell viability. These results strongly indicate that a cell culture chip could be constructed that allowed for on-line optical recording of cellular events without affecting the cell culturing condition...

A biocompatible micro cell culture chamber (microCCC) for the culturing and on-line monitoring of eukaryote cells

DEFF Research Database (Denmark)

Stangegaard, Michael; Petronis, Sarunas; Jørgensen, A M

2006-01-01

culture chip compared to cell culture flasks. The cell culture chip could without further modification support cell growth of two other cell lines. Light coming from the microscope lamp during optical recordings of the cells was the only external factor identified, that could have a negative effect...... on cell survival. Low grade light exposure was however compatible with optical recordings as well as cell viability. These results strongly indicate that a cell culture chip could be constructed that allowed for on-line optical recording of cellular events without affecting the cell culturing condition...

Closed-channel culture system for efficient and reproducible differentiation of human pluripotent stem cells into islet cells

International Nuclear Information System (INIS)

Hirano, Kunio; Konagaya, Shuhei; Turner, Alexander; Noda, Yuichiro; Kitamura, Shigeru; Kotera, Hidetoshi; Iwata, Hiroo

2017-01-01

Human pluripotent stem cells (hPSCs) are thought to be a promising cell-source solution for regenerative medicine due to their indefinite proliferative potential and ability to differentiate to functional somatic cells. However, issues remain with regard to achieving reproducible differentiation of cells with the required functionality for realizing human transplantation therapies and with regard to reducing the potential for bacterial or fungal contamination. To meet these needs, we have developed a closed-channel culture device and corresponding control system. Uniformly-sized spheroidal hPSCs aggregates were formed inside wells within a closed-channel and maintained continuously throughout the culture process. Functional islet-like endocrine cell aggregates were reproducibly induced following a 30-day differentiation protocol. Our system shows an easily scalable, novel method for inducing PSC differentiation with both purity and functionality. - Highlights: • A simple, closed-channel-based, semi-automatic culture system is proposed. • Uniform cell aggregate formation and culture is realized in microwell structure. • Functional islet cells are successfully induced following 30-plus-day protocol. • System requires no daily medium replacement and reduces contamination risk.

Interleukin-1beta-induced release of matrix proteins into culture media causes inhibition of mineralization of nodules formed by periodontal ligament cells in vitro.

Science.gov (United States)

Chien, H H; Lin, W L; Cho, M I

1999-05-01

The mechanism by which interleukin-1beta (IL-1) inhibits the formation of mineralized tissue nodules by periodontal ligament (PDL) cells in vitro was investigated through the processes of morphological analysis, immunoprecipitation, and Northern blot analysis. PDL cells were obtained from a 2-day-old coagulum in tooth socket and cultured in Dulbecco's Modified Eagle Medium (DMEM) containing 10% fetal bone serum (FBS) and antibiotics. Confluent cells were grown for up to 3 weeks in the presence of ascorbic acid (AA), beta-glycerophosphate (GP), and dexamethasone (Dex), or IL-1. PDL cells cultured in the presence of GP and AA did not differentiate, but those treated with Dex, GP, and AA (Dex group) underwent differentiation, showing four stages (confluent, multilayer, nodule, and mineralization) of disparate morphological characteristics. In contrast, the cells treated with IL-1, Dex, GP, and AA (IL-1 group) did form multilayers but failed to form mineralized nodules. Electron microscopy demonstrated that the Dex-induced mineralized nodules contain multilayers of fibroblastic cells, numerous collagen fibrils, and dense globular as well as fused electron dense patches that are associated with numerous apatite crystals. The nodule-like structures in the IL-1 group were also comprised of multilayered fibroblastic cells, but they contained only a small number of collagen fibrils, and no dense globular or fused patches. Von Kossa staining confirmed the presence of numerous mineralized nodules in the Dex group and their scarceness in the IL-1 group. Northern blot analysis of IL-1-treated cells, however, revealed the presence of mRNAs for type I collagen (Col I), secreted protein, acidic and rich in cysteine (SPARC), osteopontin (OPN), alkaline phosphatase (ALP), bone sialoprotein (BSP), and osteocalcin (OC), whose expression patterns and levels were comparable to those of the Dex group. Immunoprecipitation analysis of OPN and BSP in the cell/matrix layers and the culture

Tumorigenic risk of human induced pluripotent stem cell explants cultured on mouse SNL76/7 feeder cells

Energy Technology Data Exchange (ETDEWEB)

Kamada, Mizuna; Mitsui, Youji, E-mail: y-mitsui8310@hb.tp1.jp; Kumazaki, Tsutomu; Kawahara, Yuta; Matsuo, Taira; Takahashi, Tomoko, E-mail: t-takahashi@kph.bunri-u.ac.jp

2014-10-24

Highlights: • hiPS cell explants formed malignant tumors when SNL76/7 feeder cells were used. • Multi type tumors developed by interaction of SNL76/7 feeder cells with hiPS cells. • Tumorigenic risk occurs by co-culture of hiPS cells with SNL76/7 feeder cells. - Abstract: The potential for tumor formation from transplanted human induced pluripotent stem cell (hiPSC) derivatives represents a high risk in their application to regenerative medicine. We examined the genetic origin and characteristics of tumors, that were formed when 13 hiPSC lines, established by ourselves, and 201B7 hiPSC from Kyoto University were transplanted into severe combined immune-deficient (SCID) mice. Though teratomas formed in 58% of mice, five angiosarcomas, one malignant solitary fibrous tumor and one undifferentiated pleomorphic sarcoma formed in the remaining mice. Three malignant cell lines were established from the tumors, which were derived from mitomycin C (MMC)-treated SNL76/7 (MMC-SNL) feeder cells, as tumor development from fusion cells between MMC-SNL and hiPSCs was negative by genetic analysis. While parent SNL76/7 cells produced malignant tumors, neither MMC-SNL nor MMC-treated mouse embryo fibroblast (MEF) produced malignant tumors. When MMC-SNL feeder cells were co-cultured with hiPSCs, growing cell lines were generated, that expressed genes similar to the parent SNL76/7 cells. Thus, hiPSCs grown on MMC-SNL feeder cells have a high risk of generating feeder-derived malignant tumors. The possible mechanism(s) of growth restoration and the formation of multiple tumor types are discussed with respect of the interactions between MMC-SNL and hiPSC.

Transforming growth factor-beta1 promotes the migration and invasion of sphere-forming stem-like cell subpopulations in esophageal cancer

Energy Technology Data Exchange (ETDEWEB)

Yue, Dongli; Zhang, Zhen; Li, Jieyao; Chen, Xinfeng [Biotherapy Center, the First Affiliated Hospital of Zhengzhou University, No. 1 Jianshe Road, Zhengzhou 450052, Henan, PR China (China); Department of Oncology, the First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052 (China); Ping, Yu; Liu, Shasha [Biotherapy Center, the First Affiliated Hospital of Zhengzhou University, No. 1 Jianshe Road, Zhengzhou 450052, Henan, PR China (China); School of Life Sciences, Zhengzhou University, Zhengzhou 450000 (China); Shi, Xiaojuan; Li, Lifeng [Biotherapy Center, the First Affiliated Hospital of Zhengzhou University, No. 1 Jianshe Road, Zhengzhou 450052, Henan, PR China (China); Department of Oncology, the First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052 (China); Wang, Liping [Department of Oncology, the First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052 (China); Huang, Lan [Biotherapy Center, the First Affiliated Hospital of Zhengzhou University, No. 1 Jianshe Road, Zhengzhou 450052, Henan, PR China (China); Zhang, Bin [Biotherapy Center, the First Affiliated Hospital of Zhengzhou University, No. 1 Jianshe Road, Zhengzhou 450052, Henan, PR China (China); Robert H. Lurie Comprehensive Cancer Center, Department of Medicine-Division of Hematology/Oncology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 (United States); Sun, Yan [Department of Oncology, the First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052 (China); Department of Medical Oncology, Cancer Hospital, Chinese Academy of Medical Sciences (China); and others

2015-08-01

Esophageal cancer is one of the most lethal solid malignancies. Mounting evidence demonstrates that cancer stem cells (CSCs) are able to cause tumor initiation, metastasis and responsible for chemotherapy and radiotherapy failures. As CSCs are thought to be the main reason of therapeutic failure, these cells must be effectively targeted to elicit long-lasting therapeutic responses. We aimed to enrich and identify the esophageal cancer cell subpopulation with stem-like properties and help to develop new target therapy strategies for CSCs. Here, we found esophageal cancer cells KYSE70 and TE1 could form spheres in ultra low attachment surface culture and be serially passaged. Sphere-forming cells could redifferentiate and acquire morphology comparable to parental cells, when return to adherent culture. The sphere-forming cells possessed the key criteria that define CSCs: persistent self-renewal, overexpression of stemness genes (SOX2, ALDH1A1 and KLF4), reduced expression of differentiation marker CK4, chemoresistance, strong invasion and enhanced tumorigenic potential. SB525334, transforming growth factor-beta 1(TGF-β1) inhibitor, significantly inhibited migration and invasion of sphere-forming stem-like cells and had no effect on sphere-forming ability. In conclusion, esophageal cancer sphere-forming cells from KYSE70 and TE1 cultured in ultra low attachment surface possess cancer stem cell properties, providing a model for CSCs targeted therapy. TGF-β1 promotes the migration and invasion of sphere-forming stem-like cells, which may guide future studies on therapeutic strategies targeting these cells. - Highlights: • Esophageal cancer sphere-forming cells possess cancer stem cell properties. • Sphere-forming cells enhance TGF-β1 pathway activity. • TGF-β 1 inhibitor suppresses the migration and invasion of sphere-forming cells.

Transforming growth factor-beta1 promotes the migration and invasion of sphere-forming stem-like cell subpopulations in esophageal cancer

International Nuclear Information System (INIS)

Yue, Dongli; Zhang, Zhen; Li, Jieyao; Chen, Xinfeng; Ping, Yu; Liu, Shasha; Shi, Xiaojuan; Li, Lifeng; Wang, Liping; Huang, Lan; Zhang, Bin; Sun, Yan

2015-01-01

Esophageal cancer is one of the most lethal solid malignancies. Mounting evidence demonstrates that cancer stem cells (CSCs) are able to cause tumor initiation, metastasis and responsible for chemotherapy and radiotherapy failures. As CSCs are thought to be the main reason of therapeutic failure, these cells must be effectively targeted to elicit long-lasting therapeutic responses. We aimed to enrich and identify the esophageal cancer cell subpopulation with stem-like properties and help to develop new target therapy strategies for CSCs. Here, we found esophageal cancer cells KYSE70 and TE1 could form spheres in ultra low attachment surface culture and be serially passaged. Sphere-forming cells could redifferentiate and acquire morphology comparable to parental cells, when return to adherent culture. The sphere-forming cells possessed the key criteria that define CSCs: persistent self-renewal, overexpression of stemness genes (SOX2, ALDH1A1 and KLF4), reduced expression of differentiation marker CK4, chemoresistance, strong invasion and enhanced tumorigenic potential. SB525334, transforming growth factor-beta 1(TGF-β1) inhibitor, significantly inhibited migration and invasion of sphere-forming stem-like cells and had no effect on sphere-forming ability. In conclusion, esophageal cancer sphere-forming cells from KYSE70 and TE1 cultured in ultra low attachment surface possess cancer stem cell properties, providing a model for CSCs targeted therapy. TGF-β1 promotes the migration and invasion of sphere-forming stem-like cells, which may guide future studies on therapeutic strategies targeting these cells. - Highlights: • Esophageal cancer sphere-forming cells possess cancer stem cell properties. • Sphere-forming cells enhance TGF-β1 pathway activity. • TGF-β 1 inhibitor suppresses the migration and invasion of sphere-forming cells

Optimization of cell adhesion on mg based implant materials by pre-incubation under cell culture conditions.

Science.gov (United States)

Willumeit, Regine; Möhring, Anneke; Feyerabend, Frank

2014-05-05

Magnesium based implants could revolutionize applications where orthopedic implants such as nails, screws or bone plates are used because they are load bearing and degrade over time. This prevents a second surgery to remove conventional implants. To improve the biocompatibility we studied here if and for how long a pre-incubation of the material under cell culture conditions is favorable for cell attachment and proliferation. For two materials, Mg and Mg10Gd1Nd, we could show that 6 h pre-incubation are already enough to form a natural protective layer suitable for cell culture.

Optimization of Cell Adhesion on Mg Based Implant Materials by Pre-Incubation under Cell Culture Conditions

Directory of Open Access Journals (Sweden)

Regine Willumeit

2014-05-01

Full Text Available Magnesium based implants could revolutionize applications where orthopedic implants such as nails, screws or bone plates are used because they are load bearing and degrade over time. This prevents a second surgery to remove conventional implants. To improve the biocompatibility we studied here if and for how long a pre-incubation of the material under cell culture conditions is favorable for cell attachment and proliferation. For two materials, Mg and Mg10Gd1Nd, we could show that 6 h pre-incubation are already enough to form a natural protective layer suitable for cell culture.

Cell Adhesion Minimization by a Novel Mesh Culture Method Mechanically Directs Trophoblast Differentiation and Self-Assembly Organization of Human Pluripotent Stem Cells.

Science.gov (United States)

Okeyo, Kennedy Omondi; Kurosawa, Osamu; Yamazaki, Satoshi; Oana, Hidehiro; Kotera, Hidetoshi; Nakauchi, Hiromitsu; Washizu, Masao

2015-10-01

Mechanical methods for inducing differentiation and directing lineage specification will be instrumental in the application of pluripotent stem cells. Here, we demonstrate that minimization of cell-substrate adhesion can initiate and direct the differentiation of human pluripotent stem cells (hiPSCs) into cyst-forming trophoblast lineage cells (TLCs) without stimulation with cytokines or small molecules. To precisely control cell-substrate adhesion area, we developed a novel culture method where cells are cultured on microstructured mesh sheets suspended in a culture medium such that cells on mesh are completely out of contact with the culture dish. We used microfabricated mesh sheets that consisted of open meshes (100∼200 μm in pitch) with narrow mesh strands (3-5 μm in width) to provide support for initial cell attachment and growth. We demonstrate that minimization of cell adhesion area achieved by this culture method can trigger a sequence of morphogenetic transformations that begin with individual hiPSCs attached on the mesh strands proliferating to form cell sheets by self-assembly organization and ultimately differentiating after 10-15 days of mesh culture to generate spherical cysts that secreted human chorionic gonadotropin (hCG) hormone and expressed caudal-related homeobox 2 factor (CDX2), a specific marker of trophoblast lineage. Thus, this study demonstrates a simple and direct mechanical approach to induce trophoblast differentiation and generate cysts for application in the study of early human embryogenesis and drug development and screening.

Cellular heredity in haploid cultures of somatic cells. Comprehensive report, April 1975--June 1977

International Nuclear Information System (INIS)

Freed, J.J.

1977-07-01

This report reviews genetic studies carried out since 1975 on a haploid cultured cell line from frog embryos (ICR 2A). Although a single chromosome set would be expected to facilitate recovery of recessive mutants, experiments suggested that cell culture variants might arise through processes more complex than the selection of simple mutational changes. Therefore, the objectives of the work reported here have been to throw light on just how cell culture variants arise in this system. First, we have continued to characterize the ICR 2A line, with emphasis on stability of karyotype and DNA content. Second, we have studied in detail the origin of two classes of drug-resistant variants. Bromodeoxyuridine resistance of the thymidine deficiency type has been shown to arise through sequential loss of two forms of thymidine-phosphorylating enzyme; loss of the second form of enzyme is complex, suggesting that changes more complex than simple recessive mutations may be involved. Another form of resistance, in which tolerance of high levels of bromodeoxyuridine is found in cells that continue to express thymidine kinase, remains under study. Variants resistant to microtubule inhibitors were isolated. It was found that these haploid strains have properties distinguishing them from analogous resistant strains isolated from diploid mammalian cell cultures in other laboratories. In order to understand better how mutagens are involved in the origin of cell culture variants, we have examined the effect of different forms of DNA repair on the frequency of drug-resistant colonies induced by ultraviolet radiation. Preliminary experiments suggest that the frequency of such colonies is greater when repair takes place through (presumably error-prone) dark repair than when (error-free) photoreversal is allowed to occur. Such experiments can determine whether new phenotypes arise from alterations in DNA, and thus whether, in a broad sense, they are likely to be mutational in nature

Effects of different feeder layers on culture of bovine embryonic stem cell-like cells in vitro.

Science.gov (United States)

Cong, Shan; Cao, Guifang; Liu, Dongjun

2014-12-01

To find a suitable feeder layer is important for successful culture conditions of bovine embryonic stem cell-like cells. In this study, expression of pluripotency-related genes OCT4, SOX2 and NANOG in bovine embryonic stem cell-like cells on mouse embryonic fibroblast feeder layers at 1-5 passages were monitored in order to identify the possible reason that bovine embryonic stem cell-like cells could not continue growth and passage. Here, we developed two novel feeder layers, mixed embryonic fibroblast feeder layers of mouse and bovine embryonic fibroblast at different ratios and sources including mouse fibroblast cell lines. The bovine embryonic stem cell-like cells generated in our study displayed typical stem cell morphology and expressed specific markers such as OCT4, stage-specific embryonic antigen 1 and 4, alkaline phosphatase, SOX2, and NANOG mRNA levels. When feeder layers and cell growth factors were removed, the bovine embryonic stem cell-like cells formed embryoid bodies in a suspension culture. Furthermore, we compared the expression of the pluripotent markers during bovine embryonic stem cell-like cell in culture on mixed embryonic fibroblast feeder layers, including mouse fibroblast cell lines feeder layers and mouse embryonic fibroblast feeder layers by real-time quantitative polymerase chain reaction. Results suggested that mixed embryonic fibroblast and sources including mouse fibroblast cell lines feeder layers were more suitable for long-term culture and growth of bovine embryonic stem cell-like cells than mouse embryonic fibroblast feeder layers. The findings may provide useful experimental data for the establishment of an appropriate culture system for bovine embryonic stem cell lines.

A genetically modified protein-based hydrogel for 3D culture of AD293 cells.

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Xiao Du

Full Text Available Hydrogels have strong application prospects for drug delivery, tissue engineering and cell therapy because of their excellent biocompatibility and abundant availability as scaffolds for drugs and cells. In this study, we created hybrid hydrogels based on a genetically modified tax interactive protein-1 (TIP1 by introducing two or four cysteine residues in the primary structure of TIP1. The introduced cysteine residues were crosslinked with a four-armed poly (ethylene glycol having their arm ends capped with maleimide residues (4-armed-PEG-Mal to form hydrogels. In one form of the genetically modification, we incorporated a peptide sequence 'GRGDSP' to introduce bioactivity to the protein, and the resultant hydrogel could provide an excellent environment for a three dimensional cell culture of AD293 cells. The AD293 cells continued to divide and displayed a polyhedron or spindle-shape during the 3-day culture period. Besides, AD293 cells could be easily separated from the cell-gel constructs for future large-scale culture after being cultured for 3 days and treating hydrogel with trypsinase. This work significantly expands the toolbox of recombinant proteins for hydrogel formation, and we believe that our hydrogel will be of considerable interest to those working in cell therapy and controlled drug delivery.

Cell Culturing of Cytoskeleton

Science.gov (United States)

2004-01-01

Biomedical research offers hope for a variety of medical problems, from diabetes to the replacement of damaged bone and tissues. Bioreactors, which are used to grow cells and tissue cultures, play a major role in such research and production efforts. Cell culturing, such as this bone cell culture, is an important part of biomedical research. The BioDyn payload includes a tissue engineering investigation. The commercial affiliate, Millenium Biologix, Inc., has been conducting bone implant experiments to better understand how synthetic bone can be used to treat bone-related illnesses and bone damaged in accidents. On STS-95, the BioDyn payload will include a bone cell culture aimed to help develop this commercial synthetic bone product. Millenium Biologix, Inc., is exploring the potential for making human bone implantable materials by seeding its proprietary artificial scaffold material with human bone cells. The product of this tissue engineering experiment using the Bioprocessing Modules (BPMs) on STS-95 is space-grown bone implants, which could have potential for dental implants, long bone grafts, and coating for orthopedic implants such as hip replacements.

[Biological characteristics of mesenchymal stem cell and hematopoietic stem cell in the co-culture system].

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Wei, Wei; Xu, Chao; Ye, Zhi-Yong; Huang, Xiao-Jun; Yuan, Jia-En; Ma, Tian-Bao; Lin, Han-Biao; Chen, Xiu-Qiong

2016-10-25

The aim of the present study was to obtain the qualified hematopoietic stem/progenitor cells (HSC/HPC) and human umbilical cord-mesenchymal stem cells (MSC) in vitro in the co-culture system. Cord blood mononuclear cells were separated from umbilical cord blood by Ficoll lymphocyte separation medium, and then CD34 + HSC was collected by MACS immunomagnetic beads. The selected CD34 + HSC/HPC and MSC were transferred into culture flask. IMDM culture medium with 15% AB-type cord plasma supplemented with interleukin-3 (IL-3), IL-6, thrombopoietin (TPO), stem cell factor (SCF) and FMS-like tyrosine kinase 3 ligand (Flt-3L) factors were used as the co-culture system for the amplification of HSC/HPC and MSC. The cellular growth status and proliferation on day 6 and 10 after co-culture were observed by using inverted microscope. The percentage of positive expression of CD34 in HSC/HPC, as well as the percentages of positive expressions of CD105, CD90, CD73, CD45, CD34 and HLA-DR in the 4 th generation MSC, was tested by flow cytometry. Semisolid colony culture was used to test the HSC/HPC colony forming ability. The osteogenic, chondrogenesis and adipogenic ability of the 4 th generation MSC were assessed. The karyotype analysis of MSC was conducted by colchicines. The results demonstrated that the HSC/HPC of co-culture group showed higher ability of amplification, CFU-GM and higher CD34 + percentage compared with the control group. The co-cultured MSC maintained the ability to differentiate into bone cells, fat cells and chondrocytes. And the karyotype stability of MSC remained normal. These results reveal that the appropriate co-culture system for MSC and HSC is developed, and via this co-culture system we could gain both two kinds of these cells. The MSCs under the co-culture system maintain the biological characteristics. The CFU-GM ability, cell counting and the flow cytometry results of HSC/HPC under the co-culture system are conform to the criterion, showing that

9 CFR 101.6 - Cell cultures.

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2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Cell cultures. 101.6 Section 101.6..., SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS DEFINITIONS § 101.6 Cell cultures. When used in conjunction with or in reference to cell cultures, which may be referred to as tissue cultures...

Importance of Sox2 in maintenance of cell proliferation and multipotency of mesenchymal stem cells in low-density culture.

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Yoon, D S; Kim, Y H; Jung, H S; Paik, S; Lee, J W

2011-10-01

This study has aimed to repopulate 'primitive' cells from late-passage mesenchymal stem cells (MSCs) of poor multipotentiality and low cell proliferation rate, by simply altering plating density. Effects of low density culture compared t high density culture on late-passage bone marrow (BM)-derived MSCs and pluripotency markers of multipotentiality were investigated. Cell proliferation, gene expression, RNA interference and differentiation potential were assayed. We repopulated 'primitive' cells by replating late-passage MSCs at low density (17 cells/cm(2) ) regardless of donor age. Repopulated MSCs from low-density culture were smaller cells with spindle shaped morphology compared to MSCs from high-density culture. The latter had enhanced colony-forming ability, proliferation rate, and adipogenic and chondrogenic potential. Strong expression of osteogenic-related genes (Cbfa1, Dlx5, alkaline phosphatase and type Ι collagen) in late-passage MSCs was reduced by replating at low density, whereas expression of three pluripotency markers (Sox2, Nanog and Oct-4), Osterix and Msx2 reverted to levels of early-passage MSCs. Knockdown of Sox2 and Msx2 but not Nanog, using RNA interference, showed significant decrease in colony-forming ability. Specifically, knockdown of Sox2 significantly inhibited multipotentiality and cell proliferation. Our data suggest that plating density should be considered to be a critical factor for enrichment of 'primitive' cells from heterogeneous BM and that replicative senescence and multipotentiality of MSCs during in vitro expansion may be predominantly regulated through Sox2. © 2011 Blackwell Publishing Ltd.

Three-Dimensional Cell Culture Models for Infectious Disease and Drug Development

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Nickerson, Cheryl A.; Honer zu Bentrup, Kerstin; Ott, C. Mark

2005-01-01

Three-dimensional (3-D) cell cultures hold enormous potential to advance our understanding of infectious disease and to effectively translate basic cellular research into clinical applications. Using novel NASA bioreactor technology, the rotating wall vessel (RWV), we have engineered physiologically relevant 3-D human tissue culture models for infectious disease studies. The design of the RWV is based on the understanding that organs and tissues function in a 3-D environment, and that this 3-D architecture is critical for the differentiated form and function of tissues in vivo. The RWV provides large numbers of cells which are amenable to a wide variety of experimental manipulations and provides an easy, reproducible, and cost-effective approach to enhance differentiated features of cell culture models.

Relationship of colony-stimulating activity to apparent kill of human colony-forming cells by irradiation and hydroxyurea

International Nuclear Information System (INIS)

Broxmeyer, H.E.; Galbraith, P.R.; Baker, F.L.

1976-01-01

Suspensions of human bone marrow cells were subjected to 137 Cs irradiation in vitro and then cultured in semisolid agar medium. Cultures of irradiated cells were stimulated with colony-stimulating activity (CSA) of different potencies, and it was found that the amount of stimulation applied to cultures influenced the apparent kill of colony-forming cells (CFC). It was also found that the effects of irradiation on colony formation were not confined to CFC kill since medium conditioned by cells during irradiation exhibited stimulatory and inhibitory properties after treatment by 600 and 1000 rads, respectively. Studies in which irradiated cells were pretreated with hydroxyurea indicated that CFC in the DNA synthetic phase of the cell cycle were particularly sensitive to low doses of irradiation. The proliferative capacity of CFC surviving 1000 rads was undiminished as judged by their ability to form large colonies. Estimates of CFC kill by hydroxyurea were also affected by the level of CSA

Effect of D-valine and cytosine arabinoside on [3H]thymidine incorporation in rat and rabbit epididymal epithelial cell cultures

International Nuclear Information System (INIS)

Orgebin-Crist, M.C.; Jonas-Davies, J.; Storey, P.; Olson, G.E.

1984-01-01

Epithelial cell enriched primary cultures were established from the rat and the rabbit epididymis. Epithelial cell aggregates, obtained after pronase digestion of minced epididymis, attached to the culture dish and after 72 h in vitro spread out to form discrete patches of cells. These cells have an epithelioid morphology and form a monolayer of closely apposed polygonal cells where DNA synthesis, as judged by [ 3 H]thymidine uptake, is very low. In L-valine medium the nonepithelial cell contamination was no more than 10% in rat and rabbit epididymal primary cultures. The labeling index of rat epididymal cells cultured in D-valine medium was significantly lower than that of cells cultured in L-valine medium. In contrast, the labeling index of rabbit epididymal cells cultured in D-valine medium was significantly higher than that of cells cultured in L-valine medium. Cytosine arabinoside decreased the number of labeled cells in both L-valine and D-valine cultures. From these results, it appears that D-valine is a selective agent for rat epididymal epithelial cells, but not for rabbit epithelial cells, and that cytosine arabinoside is a simple and effective means to control the proliferation of fibroblast-like cells in both rat and rabbit epididymal cell cultures

Establishment of Cancer Stem Cell Cultures from Human Conventional Osteosarcoma.

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Palmini, Gaia; Zonefrati, Roberto; Mavilia, Carmelo; Aldinucci, Alessandra; Luzi, Ettore; Marini, Francesca; Franchi, Alessandro; Capanna, Rodolfo; Tanini, Annalisa; Brandi, Maria Luisa

2016-10-14

The current improvements in therapy against osteosarcoma (OS) have prolonged the lives of cancer patients, but the survival rate of five years remains poor when metastasis has occurred. The Cancer Stem Cell (CSC) theory holds that there is a subset of tumor cells within the tumor that have stem-like characteristics, including the capacity to maintain the tumor and to resist multidrug chemotherapy. Therefore, a better understanding of OS biology and pathogenesis is needed in order to advance the development of targeted therapies to eradicate this particular subset and to reduce morbidity and mortality among patients. Isolating CSCs, establishing cell cultures of CSCs, and studying their biology are important steps to improving our understanding of OS biology and pathogenesis. The establishment of human-derived OS-CSCs from biopsies of OS has been made possible using several methods, including the capacity to create 3-dimensional stem cell cultures under nonadherent conditions. Under these conditions, CSCs are able to create spherical floating colonies formed by daughter stem cells; these colonies are termed "cellular spheres". Here, we describe a method to establish CSC cultures from primary cell cultures of conventional OS obtained from OS biopsies. We clearly describe the several passages required to isolate and characterize CSCs.

Automation of 3D cell culture using chemically defined hydrogels.

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Rimann, Markus; Angres, Brigitte; Patocchi-Tenzer, Isabel; Braum, Susanne; Graf-Hausner, Ursula

2014-04-01

Drug development relies on high-throughput screening involving cell-based assays. Most of the assays are still based on cells grown in monolayer rather than in three-dimensional (3D) formats, although cells behave more in vivo-like in 3D. To exemplify the adoption of 3D techniques in drug development, this project investigated the automation of a hydrogel-based 3D cell culture system using a liquid-handling robot. The hydrogel technology used offers high flexibility of gel design due to a modular composition of a polymer network and bioactive components. The cell inert degradation of the gel at the end of the culture period guaranteed the harmless isolation of live cells for further downstream processing. Human colon carcinoma cells HCT-116 were encapsulated and grown in these dextran-based hydrogels, thereby forming 3D multicellular spheroids. Viability and DNA content of the cells were shown to be similar in automated and manually produced hydrogels. Furthermore, cell treatment with toxic Taxol concentrations (100 nM) had the same effect on HCT-116 cell viability in manually and automated hydrogel preparations. Finally, a fully automated dose-response curve with the reference compound Taxol showed the potential of this hydrogel-based 3D cell culture system in advanced drug development.

SAHA-induced TRAIL-sensitisation of Multiple Myeloma cells is enhanced in 3D cell culture.

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Arhoma, A; Chantry, A D; Haywood-Small, S L; Cross, N A

2017-11-15

Multiple Myeloma (MM) is currently incurable despite many novel therapies. Tumour Necrosis Factor-Related Apoptosis-Inducing Ligand (TRAIL) is a potential anti-tumour agent although effects as a single agent are limited. In this study, we investigated whether the Histone Deacetylase (HDAC) inhibitor SAHA can enhance TRAIL-induced apoptosis and target TRAIL resistance in both suspension culture, and 3D cell culture as a model of disseminated MM lesions that form in bone. The effects of SAHA and/or TRAIL in 6 Multiple Myeloma cell lines were assessed in both suspension cultures and in an Alginate-based 3D cell culture model. The effect of SAHA and/or TRAIL was assessed on apoptosis by assessment of nuclear morphology using Hoechst 33342/Propidium Iodide staining. Viable cell number was assessed by CellTiter-Glo luminescence assay, Caspase-8 and -9 activities were measured by Caspase-Glo™ assay kit. TRAIL-resistant cells were generated by culture of RPMI 8226 and NCI-H929 by acute exposure to TRAIL followed by selection of TRAIL-resistant cells. TRAIL significantly induced apoptosis in a dose-dependent manner in OPM-2, RPMI 8226, NCI-H929, U266, JJN-3 MM cell lines and ADC-1 plasma cell leukaemia cells. SAHA amplified TRAIL responses in all lines except OPM-2, and enhanced TRAIL responses were both via Caspase-8 and -9. SAHA treatment induced growth inhibition that further increased in the combination treatment with TRAIL in MM cells. The co-treatment of TRAIL and SAHA reduced viable cell numbers all cell lines. TRAIL responses were further potentiated by SAHA in 3D cell culture in NCI-H929, RPMI 8226 and U266 at lower TRAIL + SAHA doses than in suspension culture. However TRAIL responses in cells that had been selected for TRAIL resistance were not further enhanced by SAHA treatment. SAHA is a potent sensitizer of TRAIL responses in both TRAIL sensitive and resistant cell lines, in both suspension and 3D culture, however SAHA did not sensitise TRAIL-sensitive cell

Cell-cell interactions of isolated and cultured oligodendrocytes: formation of linear occluding junctions and expression of peculiar intramembrane particles.

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Massa, P T; Szuchet, S; Mugnaini, E

1984-12-01

Oligodendrocytes were isolated from lamb brain. Freshly isolated cells and cultured cells, either 1- to 4-day-old unattached or 1- to 5-week-old attached, were examined by thin section and freeze-fracture electron microscopy. Freeze-fracture of freshly isolated oligodendrocytes showed globular and elongated intramembrane particles similar to those previously described in oligodendrocytes in situ. Enrichment of these particles was seen at sites of inter-oligodendrocyte contact. Numerous gap junctions and scattered linear tight junctional arrays were apparent. Gap junctions were connected to blebs of astrocytic plasma membrane sheared off during isolation, whereas tight junctions were facing extracellular space or blebs of oligodendrocytic plasma membrane. Thin sections of cultured, unattached oligodendrocytes showed rounded cell bodies touching one another at points without forming specialized cell junctions. Cells plated on polylysine-coated aclar dishes attached, emanated numerous, pleomorphic processes, and expressed galactocerebroside and myelin basic protein, characteristic markers for oligodendrocytes. Thin sections showed typical oligodendrocyte ultrastructure but also intermediate filaments not present in unattached cultures. Freeze-fracture showed intramembrane particles similar to but more numerous, and with a different fracture face repartition, than those seen in oligodendrocytes, freshly isolated or in situ. Gap junctions were small and rare. Apposed oligodendrocyte plasma membrane formed linear tight junctions which became more numerous with time in culture. Thus, cultured oligodendrocytes isolated from ovine brains develop and maintain features characteristic of mature oligodendrocytes in situ and can be used to explore formation and maintenance of tight junctions and possibly other classes of cell-cell interactions important in the process of myelination.

Forming Future Teachers' Aesthetic Culture in Foreign Educational Practice

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Sotska, Galyna

2016-01-01

The article deals with a theoretical analysis of foreign educational experience in solving scientific problems of forming future teachers' aesthetic culture. Given the current socio-cultural situation, it has been noted that a teacher who developed his/her aesthetic culture can make a direct contribution to the social and cultural challenges of a…

Just How Many Different Forms of Culture Are There?

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Cohen, Adam B.

2010-01-01

Responds to comments by H. Takooshian and J. K. Tebes on the current author's original article, "Many forms of culture". The current author argued that psychologists tend to focus on too narrow a set of cultures (ethnic and national cultures) and some dimensions of those cultures (individualism-collectivism, independence-interdependence). He then…

Keratinocytes propagated in serum-free, feeder-free culture conditions fail to form stratified epidermis in a reconstituted skin model.

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Rebecca Lamb

Full Text Available Primary human epidermal stem cells isolated from skin tissues and subsequently expanded in tissue culture are used for human therapeutic use to reconstitute skin on patients and to generate artificial skin in culture for academic and commercial research. Classically, epidermal cells, known as keratinocytes, required fibroblast feeder support and serum-containing media for serial propagation. In alignment with global efforts to remove potential animal contaminants, many serum-free, feeder-free culture methods have been developed that support derivation and growth of these cells in 2-dimensional culture. Here we show that keratinocytes grown continually in serum-free and feeder-free conditions were unable to form into a stratified, mature epidermis in a skin equivalent model. This is not due to loss of cell potential as keratinocytes propagated in serum-free, feeder-free conditions retain their ability to form stratified epidermis when re-introduced to classic serum-containing media. Extracellular calcium supplementation failed to improve epidermis development. In contrast, the addition of serum to commercial, growth media developed for serum-free expansion of keratinocytes facilitated 3-dimensional stratification in our skin equivalent model. Moreover, the addition of heat-inactivated serum improved the epidermis structure and thickness, suggesting that serum contains factors that both aid and inhibit stratification.

Molecular purging of multiple myeloma cells by ex-vivo culture and retroviral transduction of mobilized-blood CD34+ cells

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Corneo Gianmarco

2007-07-01

Full Text Available Abstract Background Tumor cell contamination of the apheresis in multiple myeloma is likely to affect disease-free and overall survival after autografting. Objective To purge myeloma aphereses from tumor contaminants with a novel culture-based purging method. Methods We cultured myeloma-positive CD34+ PB samples in conditions that retained multipotency of hematopoietic stem cells, but were unfavourable to survival of plasma cells. Moreover, we exploited the resistance of myeloma plasma cells to retroviral transduction by targeting the hematopoietic CD34+ cell population with a retroviral vector carrying a selectable marker (the truncated form of the human receptor for nerve growth factor, ΔNGFR. We performed therefore a further myeloma purging step by selecting the transduced cells at the end of the culture. Results Overall recovery of CD34+ cells after culture was 128.5%; ΔNGFR transduction rate was 28.8% for CD34+ cells and 0% for CD138-selected primary myeloma cells, respectively. Recovery of CD34+ cells after ΔNGFR selection was 22.3%. By patient-specific Ig-gene rearrangements, we assessed a decrease of 0.7–1.4 logs in tumor load after the CD34+ cell selection, and up to 2.3 logs after culture and ΔNGFR selection. Conclusion We conclude that ex-vivo culture and retroviral-mediated transduction of myeloma leukaphereses provide an efficient tumor cell purging.

[Culture of pancreatic progenitor cells in hanging drop and on floating filter].

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Ma, Feng-xia; Chen, Fang; Chi, Ying; Yang, Shao-guang; Lu, Shi-hong; Han, Zhong-chao

2013-06-01

To construct a method to culture pancreatic progenitor cells in hanging drop and on floating filter,and to examine if pancreatic progenitor cells can differentiate into mature endocrine cells with this method. Murine embryos at day 12.5 were isolated and digested into single cells,which were then cultured in hanging drop for 24h and formed spheres.Spheres were cultured on the filter for 6 days,which floated in the dish containing medium.During culture,the expressions of pancreas duodenum homeobox-1(PDX-1)and neurogenin3(Ngn3)were determined.The expressions of endocrine and exocrine markers,insulin,glucagon,and carboxypeptidase(CPA)were determined on day 7 by immunohistochemistry.Insulin secretion of spheres stimulated by glucose was detected by ELISA.The changes of pancreatic marker expressions during culture were monitored by real-time polymerase chain reaction(PCR). One day after the culture,there were still a large amount of PDX-1 positive cells in pancreatic spheres,and these cells proliferated.On day 3,high expression of Ngn3 was detected,and the Ngn3-positive cells did not proliferate.On day 7,The expressions of endocrine and exocrine markers in the differentiated pancreatic progenitor cells were detected,which were consistent with that in vivo.Insulin was secreted by spheres upon the stimulation of glucose. In hanging drop and on floating filter,pancreatic progenitor cells can differentiate into mature endocrine cells.

Development and characterization of cell culture systems from Puntius (Tor) chelynoides (McClelland).

Science.gov (United States)

Goswami, M; Sharma, B S; Tripathi, A K; Yadav, Kamalendra; Bahuguna, S N; Nagpure, N S; Lakra, W S; Jena, J K

2012-05-25

Puntius (Tor) chelynoides, commonly known as dark mahseer, is a commercially important coldwater fish species which inhabits fast-flowing hill-streams of India and Nepal. Cell culture systems were developed from eye, fin, heart and swim bladder tissues of P. chelynoides using explant method. The cell culture system developed from eye has been maintained towards a continuous cell line designated as PCE. The cells were grown in 25cm(2) tissue culture flasks with Leibovitz' L-15 media supplemented with 20 % fetal bovine serum (FBS) at 24°C. The PCE cell line consists of predominantly fibroblast-like cells and showed high plating efficiency. The monolayer formed from the fin and heart explants were comprised of epithelial as well as fibroblast-like cells, a prominent and rhythmic heartbeat was also observed in heart explants. Monolayer formed from swim bladder explants showed the morphology of fibroblast-like cells. All the cells from different tissues are able to grow at an optimum temperature of 24°C and growth rate increased as the FBS concentration increased. The PCE cell line was characterized using amplification of mitochondrial cytochrome oxidase subunit I (COI) & 16S rRNA genes which confirmed that the cell line originated from P. chelynoides. Cytogenetic analysis of PCE cell line and cells from fin revealed a diploid count of 100 chromosomes. Upon transfection with pEGFP-C1 plasmid, bright fluorescent signals were observed, suggesting that this cell line can be used for transgenic and genetic manipulation studies. Further, genotoxicity assessment of PCE cells illustrated the utility of this cell line as an in vitro model for aquatic toxicological studies. The PCE cell line was successfully cryopreserved and revived at different passage levels. The cell line and culture systems are being maintained to develop continuous cell lines for further studies. Copyright © 2012 Elsevier B.V. All rights reserved.

Topological defects control collective dynamics in neural progenitor cell cultures

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Kawaguchi, Kyogo; Kageyama, Ryoichiro; Sano, Masaki

2017-04-01

Cultured stem cells have become a standard platform not only for regenerative medicine and developmental biology but also for biophysical studies. Yet, the characterization of cultured stem cells at the level of morphology and of the macroscopic patterns resulting from cell-to-cell interactions remains largely qualitative. Here we report on the collective dynamics of cultured murine neural progenitor cells (NPCs), which are multipotent stem cells that give rise to cells in the central nervous system. At low densities, NPCs moved randomly in an amoeba-like fashion. However, NPCs at high density elongated and aligned their shapes with one another, gliding at relatively high velocities. Although the direction of motion of individual cells reversed stochastically along the axes of alignment, the cells were capable of forming an aligned pattern up to length scales similar to that of the migratory stream observed in the adult brain. The two-dimensional order of alignment within the culture showed a liquid-crystalline pattern containing interspersed topological defects with winding numbers of +1/2 and -1/2 (half-integer due to the nematic feature that arises from the head-tail symmetry of cell-to-cell interaction). We identified rapid cell accumulation at +1/2 defects and the formation of three-dimensional mounds. Imaging at the single-cell level around the defects allowed us to quantify the velocity field and the evolving cell density; cells not only concentrate at +1/2 defects, but also escape from -1/2 defects. We propose a generic mechanism for the instability in cell density around the defects that arises from the interplay between the anisotropic friction and the active force field.

Three-dimensional hydrogel cell culture systems for modeling neural tissue

Science.gov (United States)

Frampton, John

designed for use as a tool to predict the transport and processing that occurs prior to drug uptake in the central nervous system (CNS), and to predict BBB permeability. Electrochemical techniques and immunohistochemistry were used to validate this model and provide detailed information about cellular organization and function. Electrochemical impedance spectroscopy (EIS) provided evidence that endothelial cells cultured in the presence of astrocytes formed tight junctions capable of occluding the flow of electrical current. In a second series of experiments, a microglia-astrocyte co-culture system was developed to assess the effects of glial cells on electrode impedance recorded from neural prosthetic devices in vitro. Impedance measurements were compared with confocal images to determine the effects of glial cell density and cell type on electrode performance. The results indicate that EIS data can be used to model components of the reactive cell responses in brain tissue, and that impedance measurements recorded in vitro can be compared to measurements recorded in vivo. Taken together, these results demonstrate that alginate hydrogels can be used for the creation of 3-D neural cell scaffolds, and that such cell scaffolds can be used to model a variety of three-dimensional neural tissues in vitro, that cannot be studied in 2-D cultures.

Human disc cells in monolayer vs 3D culture: cell shape, division and matrix formation

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Hanley Edward N

2000-10-01

Full Text Available Abstract Background The relationship between cell shape, proliferation, and extracellular matrix (ECM production, important aspects of cell behavior, is examined in a little-studied cell type, the human annulus cell from the intervertebral disc, during monolayer vs three-dimensional (3D culture. Results Three experimental studies showed that cells respond specifically to culture microenvironments by changes in cell shape, mitosis and ECM production: 1 Cell passages showed extensive immunohistochemical evidence of Type I and II collagens only in 3D culture. Chondroitin sulfate and keratan sulfate were abundant in both monolayer and 3D cultures. 2 Cells showed significantly greater proliferation in monolayer in the presence of platelet-derived growth factor compared to cells in 3D. 3 Cells on Matrigel™-coated monolayer substrates became rounded and formed nodular colonies, a finding absent during monolayer growth. Conclusions The cell's in vivo interactions with the ECM can regulate shape, gene expression and other cell functions. The shape of the annulus cell changes markedly during life: the young, healthy disc contains spindle shaped cells and abundant collagen. With aging and degeneration, many cells assume a strikingly different appearance, become rounded and are surrounded by unusual accumulations of ECM products. In vitro manipulation of disc cells provides an experimental window for testing how disc cells from given individuals respond when they are grown in environments which direct cells to have either spindle- or rounded-shapes. In vitro assessment of the response of such cells to platelet-derived growth factor and to Matrigel™ showed a continued influence of cell shape even in the presence of a growth factor stimulus. These findings contribute new information to the important issue of the influence of cell shape on cell behavior.

Three-dimensional spheroid culture of human umbilical cord mesenchymal stem cells promotes cell yield and stemness maintenance.

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Li, Yi; Guo, Gang; Li, Li; Chen, Fei; Bao, Ji; Shi, Yu-Jun; Bu, Hong

2015-05-01

Mesenchymal stem cell (MSC) transplantation is a promising treatment of many diseases. However, conventional techniques with cells being cultured as a monolayer result in slow cell proliferation and insufficient yield to meet clinical demands. Three-dimensional (3D) culture systems are gaining attention with regard to recreating a complex microenvironment and to understanding the conditions experienced by cells. Our aim is to establish a novel 3D system for the culture of human umbilical cord MSCs (hUC-MSCs) within a real 3D microenvironment but with no digestion or passaging. Primary hUC-MSCs were isolated and grown in serum-free medium (SFM) on a suspension Rocker system. Cell characteristics including proliferation, phenotype and multipotency were recorded. The therapeutic effects of 3D-cultured hUC-MSCs on carbon tetrachloride (CCl4)-induced acute liver failure in mouse models were examined. In the 3D Rocker system, hUC-MSCs formed spheroids in SFM and maintained high viability and active proliferation. Compared with monolayer culture, the 3D-culture system yielded more hUC-MSCs cells within the same volume. The spheroids expressed higher levels of stem cell markers and displayed stronger multipotency. After transplantation into mouse, 3D hUC-MSCs significantly promoted the secretion of interferon-γ and interleukin-6 but inhibited that of tumor necrosis factor-α, thereby alleviating liver necrosis and promoting regeneration following CCl4 injury. The 3D culture of hUC-MSCs thus promotes cell yield and stemness maintenance and represents a promising strategy for hUC-MSCs expansion on an industrial scale with great potential for cell therapy and biotechnology.

A study of chromosomal aberrations in amniotic fluid cell cultures.

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Wolstenholme, J; Crocker, M; Jonasson, J

1988-06-01

This paper represents the analysis of 1916 routine amniotic fluid specimens harvested by an in situ fixation technique in a prospective study with regard to cultural chromosome anomalies. Excluding constitutional abnormalities, 2.9 per cent of 19,432 cells analysed showed some form of chromosome anomaly, terminal deletions (57 per cent) and chromatid/chromosome breaks and gaps (18 per cent) being the most frequent, followed by interchange aberrations (13 per cent) and trisomy (5 per cent). No case was found of more than one colony from the same culture showing the same anomaly without it being present in other cultures from the same fluid. The wholly abnormal colonies had a surplus of trisomies and from the mathematical considerations presented one may infer that these are likely to reflect the presence of abnormal cells in the amniotic fluid. Partly abnormal colonies appeared at a frequency that would correspond to virtual absence of selection against chromosomally abnormal cells when cultured in vitro. The aberrations found were similar to those seen as single cell anomalies, except for chromatid breaks and exchanges. The data suggest a basic preferential induction of trisomy for chromosomes 2, 18, 21, and the Y-chromosome. Structural aberrations showed a marked clustering of breakpoints around the centromeres. The frequency of mutant cells was low (1.4 X 10(-3)) before culture was initiated. At harvest, the frequency of abnormal cells was much higher (3 X 10(-2)) corresponding to 3 X 10(-3) mutations per cell per generation accumulating over approximately ten generations in vitro.

Microfluidic cell culture systems for drug research.

Science.gov (United States)

Wu, Min-Hsien; Huang, Song-Bin; Lee, Gwo-Bin

2010-04-21

In pharmaceutical research, an adequate cell-based assay scheme to efficiently screen and to validate potential drug candidates in the initial stage of drug discovery is crucial. In order to better predict the clinical response to drug compounds, a cell culture model that is faithful to in vivo behavior is required. With the recent advances in microfluidic technology, the utilization of a microfluidic-based cell culture has several advantages, making it a promising alternative to the conventional cell culture methods. This review starts with a comprehensive discussion on the general process for drug discovery and development, the role of cell culture in drug research, and the characteristics of the cell culture formats commonly used in current microfluidic-based, cell-culture practices. Due to the significant differences in several physical phenomena between microscale and macroscale devices, microfluidic technology provides unique functionality, which is not previously possible by using traditional techniques. In a subsequent section, the niches for using microfluidic-based cell culture systems for drug research are discussed. Moreover, some critical issues such as cell immobilization, medium pumping or gradient generation in microfluidic-based, cell-culture systems are also reviewed. Finally, some practical applications of microfluidic-based, cell-culture systems in drug research particularly those pertaining to drug toxicity testing and those with a high-throughput capability are highlighted.

Use of an adaptable cell culture kit for performing lymphocyte and monocyte cell cultures in microgravity

Science.gov (United States)

Hatton, J. P.; Lewis, M. L.; Roquefeuil, S. B.; Chaput, D.; Cazenave, J. P.; Schmitt, D. A.

1998-01-01

The results of experiments performed in recent years on board facilities such as the Space Shuttle/Spacelab have demonstrated that many cell systems, ranging from simple bacteria to mammalian cells, are sensitive to the microgravity environment, suggesting gravity affects fundamental cellular processes. However, performing well-controlled experiments aboard spacecraft offers unique challenges to the cell biologist. Although systems such as the European 'Biorack' provide generic experiment facilities including an incubator, on-board 1-g reference centrifuge, and contained area for manipulations, the experimenter must still establish a system for performing cell culture experiments that is compatible with the constraints of spaceflight. Two different cell culture kits developed by the French Space Agency, CNES, were recently used to perform a series of experiments during four flights of the 'Biorack' facility aboard the Space Shuttle. The first unit, Generic Cell Activation Kit 1 (GCAK-1), contains six separate culture units per cassette, each consisting of a culture chamber, activator chamber, filtration system (permitting separation of cells from supernatant in-flight), injection port, and supernatant collection chamber. The second unit (GCAK-2) also contains six separate culture units, including a culture, activator, and fixation chambers. Both hardware units permit relatively complex cell culture manipulations without extensive use of spacecraft resources (crew time, volume, mass, power), or the need for excessive safety measures. Possible operations include stimulation of cultures with activators, separation of cells from supernatant, fixation/lysis, manipulation of radiolabelled reagents, and medium exchange. Investigations performed aboard the Space Shuttle in six different experiments used Jurkat, purified T-cells or U937 cells, the results of which are reported separately. We report here the behaviour of Jurkat and U937 cells in the GCAK hardware in ground

Principles of cancer cell culture.

Science.gov (United States)

Cree, Ian A

2011-01-01

The basics of cell culture are now relatively common, though it was not always so. The pioneers of cell culture would envy our simple access to manufactured plastics, media and equipment for such studies. The prerequisites for cell culture are a well lit and suitably ventilated laboratory with a laminar flow hood (Class II), CO(2) incubator, benchtop centrifuge, microscope, plasticware (flasks and plates) and a supply of media with or without serum supplements. Not only can all of this be ordered easily over the internet, but large numbers of well-characterised cell lines are available from libraries maintained to a very high standard allowing the researcher to commence experiments rapidly and economically. Attention to safety and disposal is important, and maintenance of equipment remains essential. This chapter should enable researchers with little prior knowledge to set up a suitable laboratory to do basic cell culture, but there is still no substitute for experience within an existing well-run laboratory.

A Simple and Robust Method for Culturing Human-Induced Pluripotent Stem Cells in an Undifferentiated State Using Botulinum Hemagglutinin.

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Kim, Mee-Hae; Matsubara, Yoshifumi; Fujinaga, Yukako; Kino-Oka, Masahiro

2018-02-01

Clinical and industrial applications of human-induced pluripotent stem cells (hiPSCs) is hindered by the lack of robust culture strategies capable of sustaining a culture in an undifferentiated state. Here, a simple and robust hiPSC-culture-propagation strategy incorporating botulinum hemagglutinin (HA)-mediated selective removal of cells deviating from an undifferentiated state is developed. After HA treatment, cell-cell adhesion is disrupted, and deviated cells detached from the central region of the colony to subsequently form tight monolayer colonies following prolonged incubation. The authors find that the temporal and dose-dependent activity of HA regulated deviated-cell removal and recoverability after disruption of cell-cell adhesion in hiPSC colonies. The effects of HA are confirmed under all culture conditions examined, regardless of hiPSC line and feeder-dependent or -free culture conditions. After routine application of our HA-treatment paradigm for serial passages, hiPSCs maintains expression of pluripotent markers and readily forms embryoid bodies expressing markers for all three germ-cell layers. This method enables highly efficient culturing of hiPSCs and use of entire undifferentiated portions without having to pick deviated cells manually. This simple and readily reproducible culture strategy is a potentially useful tool for improving the robust and scalable maintenance of undifferentiated hiPSC cultures. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Bacterial cell culture

OpenAIRE

sprotocols

2014-01-01

### Materials 1. Glass culture tubes with metal caps and labels - Growth medium, from media room or customized - Glass pipette tubes - Parafilm ### Equipment 1. Vortexer - Fireboy or Bunsen burner - Motorized pipette - Micropipettes and sterile tips ### Procedure For a typical liquid culture, use 5 ml of appropriate medium. The amount in each tube does not have to be exact if you are just trying to culture cells for their precious DNA. 1. Streak an a...

Replication of cultured lung epithelial cells

International Nuclear Information System (INIS)

Guzowski, D.; Bienkowski, R.

1986-01-01

The authors have investigated the conditions necessary to support replication of lung type 2 epithelial cells in culture. Cells were isolated from mature fetal rabbit lungs (29d gestation) and cultured on feeder layers of mitotically inactivated 3T3 fibroblasts. The epithelial nature of the cells was demonstrated by indirect immunofluorescent staining for keratin and by polyacid dichrome stain. Ultrastructural examination during the first week showed that the cells contained myofilaments, microvilli and lamellar bodies (markers for type 2 cells). The following changes were observed after the first week: increase in cell size; loss of lamellar bodies and appearance of multivesicular bodies; increase in rough endoplasmic reticulum and golgi; increase in tonafilaments and well-defined junctions. General cell morphology was good for up to 10 wk. Cells cultured on plastic surface degenerated after 1 wk. Cell replication was assayed by autoradiography of cultures exposed to ( 3 H)-thymidine and by direct cell counts. The cells did not replicate during the first week; however, between 2-10 wk the cells incorporated the label and went through approximately 6 population doublings. They have demonstrated that lung alveolar epithelial cells can replicate in culture if they are maintained on an appropriate substrate. The coincidence of ability to replicate and loss of markers for differentiation may reflect the dichotomy between growth and differentiation commonly observed in developing systems

Characterization of cell cultures derived from Lutzomyia spinicrassa (Diptera: Psychodidae) and their susceptibility to infection with Leishmania (Viannia) braziliensis.

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Zapata Lesmes, Angela Cristina; Cárdenas Castro, Estrella; Bello, Felio

2005-12-01

The sand fly Lutzomyia spinicrassa (Morales, Osorno-Mesa, Osorno & de Hoyos, 1969) is a vector of Leishmania (Viannia) braziliensis, an etiological agent of cutaneous leishmaniasis in Colombia. The present article describes, for the first time, the morphological, karyotypical, and isozymatic characteristics of cell cultures derived from L. Spinicrassa embryonic tissues as well as the interaction of L. Braziliensis with these cell cultures. L. Spinicrassa embryonated eggs and neonate larvae were taken for tissue explants. These were seeded in Grace, L-15, Grace/L-15, MM/VP12, and MK/VP12 culture media. The pH range in these media was 6.7 to 6.9 and the cultures were incubated at 28 degrees C. The MHOM/CO/86/CL250 strain of L. Braziliensis was used for experimental infection of cell cultures of L. Spinicrassa. Cell growth was achieved in L-15 medium and a confluent monolayer was obtained 180 days after the embryonated eggs were explanted. The cell morphology of the primary cell cultures was initially heterogeneous, but in the confluent monolayer of these cell cultures and in the subcultures the predominant cell types were later fibroblast-like and epithelial-like. Cultured cells were predominantly diploid (2n=8); however, significant percentages of aneuploids were also recorded. The cell culture isozyme patterns of L. Spinicrassa coincided with pupae samples from the same species. Promastigote forms of L. Braziliensis could invade cells and transform into amastigote-like forms inside them. The characteristics of cell cultures derived from L. Spinicrassa embryonic tissues were determined. These cultures emerge as a new model to study the life-cycle of L. Braziliensis.

Embryonic stem cells in scaffold-free three-dimensional cell culture: osteogenic differentiation and bone generation.

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Handschel, Jörg; Naujoks, Christian; Depprich, Rita; Lammers, Lydia; Kübler, Norbert; Meyer, Ulrich; Wiesmann, Hans-Peter

2011-07-14

Extracorporeal formation of mineralized bone-like tissue is still an unsolved challenge in tissue engineering. Embryonic stem cells may open up new therapeutic options for the future and should be an interesting model for the analysis of fetal organogenesis. Here we describe a technique for culturing embryonic stem cells (ESCs) in the absence of artificial scaffolds which generated mineralized miromasses. Embryonic stem cells were harvested and osteogenic differentiation was stimulated by the addition of dexamethasone, ascorbic acid, and ß-glycerolphosphate (DAG). After three days of cultivation microspheres were formed. These spherical three-dimensional cell units showed a peripheral zone consisting of densely packed cell layers surrounded by minerals that were embedded in the extracellular matrix. Alizarine red staining confirmed evidence of mineralization after 10 days of DAG stimulation in the stimulated but not in the control group. Transmission electron microscopy demonstrated scorching crystallites and collagenous fibrils as early indication of bone formation. These extracellular structures resembled hydroxyl apatite-like crystals as demonstrated by distinct diffraction patterns using electron diffraction analysis. The micromass culture technique is an appropriate model to form three-dimensional bone-like micro-units without the need for an underlying scaffold. Further studies will have to show whether the technique is applicable also to pluripotent stem cells of different origin. © 2011 Handschel et al; licensee BioMed Central Ltd.

Embryonic stem cells in scaffold-free three-dimensional cell culture: osteogenic differentiation and bone generation

Directory of Open Access Journals (Sweden)

Meyer Ulrich

2011-07-01

Full Text Available Abstract Extracorporeal formation of mineralized bone-like tissue is still an unsolved challenge in tissue engineering. Embryonic stem cells may open up new therapeutic options for the future and should be an interesting model for the analysis of fetal organogenesis. Here we describe a technique for culturing embryonic stem cells (ESCs in the absence of artificial scaffolds which generated mineralized miromasses. Embryonic stem cells were harvested and osteogenic differentiation was stimulated by the addition of dexamethasone, ascorbic acid, and ß-glycerolphosphate (DAG. After three days of cultivation microspheres were formed. These spherical three-dimensional cell units showed a peripheral zone consisting of densely packed cell layers surrounded by minerals that were embedded in the extracellular matrix. Alizarine red staining confirmed evidence of mineralization after 10 days of DAG stimulation in the stimulated but not in the control group. Transmission electron microscopy demonstrated scorching crystallites and collagenous fibrils as early indication of bone formation. These extracellular structures resembled hydroxyl apatite-like crystals as demonstrated by distinct diffraction patterns using electron diffraction analysis. The micromass culture technique is an appropriate model to form three-dimensional bone-like micro-units without the need for an underlying scaffold. Further studies will have to show whether the technique is applicable also to pluripotent stem cells of different origin.

Ultrasonic three-dimensional on-chip cell culture for dynamic studies of tumor immune surveillance by natural killer cells.

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Christakou, Athanasia E; Ohlin, Mathias; Önfelt, Björn; Wiklund, Martin

2015-08-07

We demonstrate a simple method for three-dimensional (3D) cell culture controlled by ultrasonic standing waves in a multi-well microplate. The method gently arranges cells in a suspension into a single aggregate in each well of the microplate and, by this, nucleates 3D tissue-like cell growth for culture times between two and seven days. The microplate device is compatible with both high-resolution optical microscopy and maintenance in a standard cell incubator. The result is a scaffold- and coating-free method for 3D cell culture that can be used for controlling the cellular architecture, as well as the cellular and molecular composition of the microenvironment in and around the formed cell structures. We demonstrate the parallel production of one hundred synthetic 3D solid tumors comprising up to thousands of human hepatocellular carcinoma (HCC) HepG2 cells, we characterize the tumor structure by high-resolution optical microscopy, and we monitor the functional behavior of natural killer (NK) cells migrating, docking and interacting with the tumor model during culture. Our results show that the method can be used for determining the collective ability of a given number of NK cells to defeat a solid tumor having a certain size, shape and composition. The ultrasound-based method itself is generic and can meet any demand from applications where it is advantageous to monitor cell culture from production to analysis of 3D tissue or tumor models using microscopy in one single microplate device.

Traditional and Modern Cell Culture in Virus Diagnosis.

Science.gov (United States)

Hematian, Ali; Sadeghifard, Nourkhoda; Mohebi, Reza; Taherikalani, Morovat; Nasrolahi, Abbas; Amraei, Mansour; Ghafourian, Sobhan

2016-04-01

Cell cultures are developed from tissue samples and then disaggregated by mechanical, chemical, and enzymatic methods to extract cells suitable for isolation of viruses. With the recent advances in technology, cell culture is considered a gold standard for virus isolation. This paper reviews the evolution of cell culture methods and demonstrates why cell culture is a preferred method for identification of viruses. In addition, the advantages and disadvantages of both traditional and modern cell culture methods for diagnosis of each type of virus are discussed. Detection of viruses by the novel cell culture methods is considered more accurate and sensitive. However, there is a need to include some more accurate methods such as molecular methods in cell culture for precise identification of viruses.

Development of microfluidic cell culture devices towards an in vitro human intestinal barrier model

DEFF Research Database (Denmark)

Tan, Hsih-Yin

to enable real-time detection of cell responses, adjustment of cellular stimulation etc. leading to establishment of conditional experiments. In this project, microfluidic systems engineering was leveraged to develop an eight chamber multi-layer microchip for intestinal barrier studies. Sandwiched between...... the layers was a modified Teflon porous membrane for cell culture. The novelty lies in modifying the surface of the porous Teflon support membrane using thiol-ene ‘click’ chemistry, thus allowing the modified Teflon membrane to be bonded between the chip layers to form an enclosed microchip. Successful...... application of the multi-layer microchip was demonstrated by integrating the microchip to an existing cell culture fluidic system to culture the human intestinal epithelial cells, Caco-2, for long term studies. Under the continuous low flow conditions, the cells differentiated into columnar cells displaying...

Metabolic cooperation between co-cultured lung cancer cells and lung fibroblasts.

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Koukourakis, Michael I; Kalamida, Dimitra; Mitrakas, Achilleas G; Liousia, Maria; Pouliliou, Stamatia; Sivridis, Efthimios; Giatromanolaki, Alexandra

2017-11-01

Cooperation of cancer cells with stromal cells, such as cancer-associated fibroblasts (CAFs), has been revealed as a mechanism sustaining cancer cell survival and growth. In the current study, we focus on the metabolic interactions of MRC5 lung fibroblasts with lung cancer cells (A549 and H1299) using co-culture experiments and studying changes of the metabolic protein expression profile and of their growth and migration abilities. Using western blotting, confocal microscopy and RT-PCR, we observed that in co-cultures MRC5 respond by upregulating pyruvate dehydrogenase (PDH) and the monocarboxylate transporter MCT1. In contrast, cancer cells increase the expression of glucose transporters (GLUT1), LDH5, PDH kinase and the levels of phosphorylated/inactivated pPDH. H1299 cells growing in the same culture medium with fibroblasts exhibit a 'metastasis-like' phenomenon by forming nests within the fibroblast area. LDH5 and pPDH were drastically upregulated in these nests. The growth rate of both MRC5 and cancer cells increased in co-cultures. Suppression of LDHA or PDK1 in cancer cells abrogates the stimulatory signal from cancer cells to fibroblasts. Incubation of MRC5 fibroblasts with lactate resulted in an increase of LDHB and of PDH expression. Silencing of PDH gene in fibroblasts, or silencing of PDK1 or LDHA gene in tumor cells, impedes cancer cell's migration ability. Overall, a metabolic cooperation between lung cancer cells and fibroblasts has been confirmed in the context of direct Warburg effect, thus the fibroblasts reinforce aerobic metabolism to support the intensified anaerobic glycolytic pathways exploited by cancer cells.

Cellular heredity in haploid cultures of somatic cells. Comprehensive report, April 1975--June 1977. [UV radiation

Energy Technology Data Exchange (ETDEWEB)

Freed, J.J.

1977-07-01

This report reviews genetic studies carried out since 1975 on a haploid cultured cell line from frog embryos (ICR 2A). Although a single chromosome set would be expected to facilitate recovery of recessive mutants, experiments suggested that cell culture variants might arise through processes more complex than the selection of simple mutational changes. Therefore, the objectives of the work reported here have been to throw light on just how cell culture variants arise in this system. First, we have continued to characterize the ICR 2A line, with emphasis on stability of karyotype and DNA content. Second, we have studied in detail the origin of two classes of drug-resistant variants. Bromodeoxyuridine resistance of the thymidine deficiency type has been shown to arise through sequential loss of two forms of thymidine-phosphorylating enzyme; loss of the second form of enzyme is complex, suggesting that changes more complex than simple recessive mutations may be involved. Another form of resistance, in which tolerance of high levels of bromodeoxyuridine is found in cells that continue to express thymidine kinase, remains under study. Variants resistant to microtubule inhibitors were isolated. It was found that these haploid strains have properties distinguishing them from analogous resistant strains isolated from diploid mammalian cell cultures in other laboratories. In order to understand better how mutagens are involved in the origin of cell culture variants, we have examined the effect of different forms of DNA repair on the frequency of drug-resistant colonies induced by ultraviolet radiation. Preliminary experiments suggest that the frequency of such colonies is greater when repair takes place through (presumably error-prone) dark repair than when (error-free) photoreversal is allowed to occur. Such experiments can determine whether new phenotypes arise from alterations in DNA, and thus whether, in a broad sense, they are likely to be mutational in nature.

Elimination of remaining undifferentiated induced pluripotent stem cells in the process of human cardiac cell sheet fabrication using a methionine-free culture condition.

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Matsuura, Katsuhisa; Kodama, Fumiko; Sugiyama, Kasumi; Shimizu, Tatsuya; Hagiwara, Nobuhisa; Okano, Teruo

2015-03-01

Cardiac tissue engineering is a promising method for regenerative medicine. Although we have developed human cardiac cell sheets by integration of cell sheet-based tissue engineering and scalable bioreactor culture, the risk of contamination by induced pluripotent stem (iPS) cells in cardiac cell sheets remains unresolved. In the present study, we established a novel culture method to fabricate human cardiac cell sheets with a decreased risk of iPS cell contamination while maintaining viabilities of iPS cell-derived cells, including cardiomyocytes and fibroblasts, using a methionine-free culture condition. When cultured in the methionine-free condition, human iPS cells did not survive without feeder cells and could not proliferate or form colonies on feeder cells or in coculture with cells for cardiac cell sheet fabrication. When iPS cell-derived cells after the cardiac differentiation were transiently cultured in the methionine-free condition, gene expression of OCT3/4 and NANOG was downregulated significantly compared with that in the standard culture condition. Furthermore, in fabricated cardiac cell sheets, spontaneous and synchronous beating was observed in the whole area while maintaining or upregulating the expression of various cardiac and extracellular matrix genes. These findings suggest that human iPS cells are methionine dependent and a methionine-free culture condition for cardiac cell sheet fabrication might reduce the risk of iPS cell contamination.

Application of cell co-culture system to study fat and muscle cells.

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Pandurangan, Muthuraman; Hwang, Inho

2014-09-01

Animal cell culture is a highly complex process, in which cells are grown under specific conditions. The growth and development of these cells is a highly unnatural process in vitro condition. Cells are removed from animal tissues and artificially cultured in various culture vessels. Vitamins, minerals, and serum growth factors are supplied to maintain cell viability. Obtaining result homogeneity of in vitro and in vivo experiments is rare, because their structure and function are different. Living tissues have highly ordered complex architecture and are three-dimensional (3D) in structure. The interaction between adjacent cell types is quite distinct from the in vitro cell culture, which is usually two-dimensional (2D). Co-culture systems are studied to analyze the interactions between the two different cell types. The muscle and fat co-culture system is useful in addressing several questions related to muscle modeling, muscle degeneration, apoptosis, and muscle regeneration. Co-culture of C2C12 and 3T3-L1 cells could be a useful diagnostic tool to understand the muscle and fat formation in animals. Even though, co-culture systems have certain limitations, they provide a more realistic 3D view and information than the individual cell culture system. It is suggested that co-culture systems are useful in evaluating the intercellular communication and composition of two different cell types.

Microfluidically supported biochip design for culture of endothelial cell layers with improved perfusion conditions.

Science.gov (United States)

Raasch, Martin; Rennert, Knut; Jahn, Tobias; Peters, Sven; Henkel, Thomas; Huber, Otmar; Schulz, Ingo; Becker, Holger; Lorkowski, Stefan; Funke, Harald; Mosig, Alexander

2015-03-02

Hemodynamic forces generated by the blood flow are of central importance for the function of endothelial cells (ECs), which form a biologically active cellular monolayer in blood vessels and serve as a selective barrier for macromolecular permeability. Mechanical stimulation of the endothelial monolayer induces morphological remodeling in its cytoskeleton. For in vitro studies on EC biology culture devices are desirable that simulate conditions of flow in blood vessels and allow flow-based adhesion/permeability assays under optimal perfusion conditions. With this aim we designed a biochip comprising a perfusable membrane that serves as cell culture platform multi-organ-tissue-flow (MOTiF biochip). This biochip allows an effective supply with nutrition medium, discharge of catabolic cell metabolites and defined application of shear stress to ECs under laminar flow conditions. To characterize EC layers cultured in the MOTiF biochip we investigated cell viability, expression of EC marker proteins and cell adhesion molecules of ECs dynamically cultured under low and high shear stress, and compared them with an endothelial culture in established two-dimensionally perfused flow chambers and under static conditions. We show that ECs cultured in the MOTiF biochip form a tight EC monolayer with increased cellular density, enhanced cell layer thickness, presumably as the result of a rapid and effective adaption to shear stress by remodeling of the cytoskeleton. Moreover, endothelial layers in the MOTiF biochip express higher amounts of EC marker proteins von-Willebrand-factor and PECAM-1. EC layers were highly responsive to stimulation with TNFα as detected at the level of ICAM-1, VCAM-1 and E-selectin expression and modulation of endothelial permeability in response to TNFα/IFNγ treatment under flow conditions. Compared to static and two-dimensionally perfused cell culture condition we consider MOTiF biochips as a valuable tool for studying EC biology in vitro under

Design of 3D printed insert for hanging culture of Caco-2 cells

International Nuclear Information System (INIS)

Shen, Chong; Meng, Qin; Zhang, Guoliang

2015-01-01

A Caco-2 cell culture on Transwell, an alternative testing to animal or human testing used in evaluating drug intestinal permeability, incorrectly estimated the absorption of actively transported drugs due to the low expression of membrane transporters. Similarly, three-dimensional (3D) cultures of Caco-2 cells, which have been recommended to be more physiological relevant, were not superior to the Transwell culture in either accuracy or convenience in drug permeability testing. Using rapid 3D printing prototyping techniques, this study proposed a hanging culture of Caco-2 cells that performed with high accuracy in predicting drug permeability in humans. As found, hanging cultured Caco-2 cells formed a confluent monolayer and maintained high cell viability on the 3D printed insert. Compared with the normal culture on Transwell, the Caco-2 cells on the 3D printed insert presented ∼30–100% higher brush border enzyme activity and ∼2–7 folds higher activity of P-glycoprotein/multidrug resistance-associated protein 2 during 21 days of incubation. For the eight membrane transporter substrates, the predictive curve of the 3D printing culture exhibited better linearity (R 2  = 0.92) to the human oral adsorption than that of the Transwell culture (R 2  = 0.84), indicating better prediction by the 3D printing culture. In this regard, the 3D printed insert for hanging culture could be potentially developed as a convenient and low-cost tool for testing drug oral absorption. (paper)

Oxygen tension is a determinant of the matrix-forming phenotype of cultured human meniscal fibrochondrocytes.

Directory of Open Access Journals (Sweden)

Adetola B Adesida

Full Text Available BACKGROUND: Meniscal cartilage displays a poor repair capacity, especially when injury is located in the avascular region of the tissue. Cell-based tissue engineering strategies to generate functional meniscus substitutes is a promising approach to treat meniscus injuries. Meniscus fibrochondrocytes (MFC can be used in this approach. However, MFC are unable to retain their phenotype when expanded in culture. In this study, we explored the effect of oxygen tension on MFC expansion and on their matrix-forming phenotype. METHODOLOGY/PRINCIPAL FINDINGS: MFC were isolated from human menisci followed by basic fibroblast growth factor (FGF-2 mediated cell expansion in monolayer culture under normoxia (21%O(2 or hypoxia (3%O(2. Normoxia and hypoxia expanded MFC were seeded on to a collagen scaffold. The MFC seeded scaffolds (constructs were cultured in a serum free chondrogenic medium for 3 weeks under normoxia and hypoxia. Constructs containing normoxia-expanded MFC were subsequently cultured under normoxia while those formed from hypoxia-expanded MFC were subsequently cultured under hypoxia. After 3 weeks of in vitro culture, the constructs were assessed biochemically, histologically and for gene expression via real-time reverse transcription-PCR assays. The results showed that constructs under normoxia produced a matrix with enhanced mRNA ratio (3.5-fold higher; p<0.001 of collagen type II to I. This was confirmed by enhanced deposition of collagen II using immuno-histochemistry. Furthermore, the constructs under hypoxia produced a matrix with higher mRNA ratio of aggrecan to versican (3.5-fold, p<0.05. However, both constructs had the same capacity to produce a glycosaminoglycan (GAG -specific extracellular matrix. CONCLUSIONS: Our data provide evidence that oxygen tension is a key player in determining the matrix phenotype of cultured MFC. These findings suggest that the use of normal and low oxygen tension during MFC expansion and subsequent neo

Properties of Dental Pulp-derived Mesenchymal Stem Cells and the Effects of Culture Conditions.

Science.gov (United States)

Kawashima, Nobuyuki; Noda, Sonoko; Yamamoto, Mioko; Okiji, Takashi

2017-09-01

Dental pulp mesenchymal stem cells (DPMSCs) highly express mesenchymal stem cell markers and possess the potential to differentiate into neural cells, osteoblasts, adipocytes, and chondrocytes. Thus, DPMSCs are considered suitable for tissue regeneration. The colony isolation method has commonly been used to collect relatively large amounts of heterogeneous DPMSCs. Homogenous DPMSCs can be isolated by fluorescence-activated cell sorting using antibodies against mesenchymal stem cell markers, although this method yields a limited number of cells. Both quality and quantity of DPMSCs are critical to regenerative therapy, and cell culture methods need to be improved. We thus investigated the properties of DPMSCs cultured with different methods. DPMSCs in a three-dimensional spheroid culture system, which is similar to the hanging drop culture for differentiation of embryonic stem cells, showed upregulation of odonto-/osteoblastic markers and mineralized nodule formation. This suggests that this three-dimensional spheroid culturing system for DPMSCs may be suitable for inducing hard tissues. We further examined the effect of cell culture density on the properties of DPMSCs because the properties of stem cells can be altered depending on the cell density. DPMSCs cultured under the confluent cell density condition showed slight downregulation of some mesenchymal stem cell markers compared with those under the sparse condition. The ability of DPMSCs to differentiate into hard tissue-forming cells was found to be enhanced in the confluent condition, suggesting that the confluent culture condition may not be suitable for maintaining the stemness of DPMSCs. When DPMSCs are to be used for hard tissue regeneration, dense followed by sparse cell culture conditions may be a better alternative strategy. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

High cell density suppresses BMP4-induced differentiation of human pluripotent stem cells to produce macroscopic spatial patterning in a unidirectional perfusion culture chamber.

Science.gov (United States)

Tashiro, Shota; Le, Minh Nguyen Tuyet; Kusama, Yuta; Nakatani, Eri; Suga, Mika; Furue, Miho K; Satoh, Taku; Sugiura, Shinji; Kanamori, Toshiyuki; Ohnuma, Kiyoshi

2018-04-19

Spatial pattern formation is a critical step in embryogenesis. Bone morphogenetic protein 4 (BMP4) and its inhibitors are major factors for the formation of spatial patterns during embryogenesis. However, spatial patterning of the human embryo is unclear because of ethical issues and isotropic culture environments resulting from conventional culture dishes. Here, we utilized human pluripotent stem cells (hiPSCs) and a simple anisotropic (unidirectional perfusion) culture chamber, which creates unidirectional conditions, to measure the cell community effect. The influence of cell density on BMP4-induced differentiation was explored during static culture using a conventional culture dish. Immunostaining of the early differentiation marker SSEA-1 and the mesendoderm marker BRACHYURY revealed that high cell density suppressed differentiation, with small clusters of differentiated and undifferentiated cells formed. Addition of five-fold higher concentration of BMP4 showed similar results, suggesting that suppression was not caused by depletion of BMP4 but rather by high cell density. Quantitative RT-PCR array analysis showed that BMP4 induced multi-lineage differentiation, which was also suppressed under high-density conditions. We fabricated an elongated perfusion culture chamber, in which proteins were transported unidirectionally, and hiPSCs were cultured with BMP4. At low density, the expression was the same throughout the chamber. However, at high density, SSEA-1 and BRACHYURY were expressed only in upstream cells, suggesting that some autocrine/paracrine factors inhibited the action of BMP4 in downstream cells to form the spatial pattern. Human iPSCs cultured in a perfusion culture chamber might be useful for studying in vitro macroscopic pattern formation in human embryogenesis. Copyright © 2018 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Co-culture of Adult Mesenchymal Stem Cells and Nucleus Pulposus Cells in Bilaminar Pellets for Intervertebral Disc Regeneration.

Science.gov (United States)

Allon, Aliza A; Schneider, Richard A; Lotz, Jeffrey C

2009-01-01

Our goal is to optimize stem cell-based tissue engineering strategies in the context of the intervertebral disc environment. We explored the benefits of co-culturing nucleus pulposus cells (NPC) and adult mesenchymal stem cells (MSC) using a novel spherical bilaminar pellet culture system where one cell type is enclosed in a sphere of the other cell type. Our 3D system provides a structure that exploits embryonic processes such as tissue induction and condensation. We observed a unique phenomenon: the budding of co-culture pellets and the formation of satellite pellets that separate from the main pellet. MSC and NPC co-culture pellets were formed with three different structural organizations. The first had random organization. The other two had bilaminar organization with either MSC inside and NPC outside or NPC inside and MSC outside. By 14 days, all co-culture pellets exhibited budding and spontaneously generated satellite pellets. The satellite pellets were composed of both cell types and, surprisingly, all had the same bilaminar organization with MSC on the inside and NPC on the outside. This organization was independent of the structure of the main pellet that the satellites stemmed from. The main pellets generated satellite pellets that spontaneously organized into a bilaminar structure. This implies that structural organization occurs naturally in this cell culture system and may be inherently favorable for cell-based tissue engineering strategies. The occurrence of budding and the organization of satellite pellets may have important implications for the use of co-culture pellets in cell-based therapies for disc regeneration. From a therapeutic point of view, the generation of satellite pellets may be a beneficial feature that would serve to spread donor cells throughout the host matrix and restore normal matrix composition in a sustainable way, ultimately renewing tissue function.

Forming Future Teachers’ Aesthetic Culture in Foreign Educational Practice

OpenAIRE

Sotska Galyna

2016-01-01

The article deals with a theoretical analysis of foreign educational experience in solving scientific problems of forming future teachers’ aesthetic culture. Given the current socio-cultural situation, it has been noted that a teacher who developed his/her aesthetic culture can make a direct contribution to the social and cultural challenges of a changing world. Based on the study of scientific and pedagogical literature, normative and legal support and the content of practical courses, the a...

Oscillating Cell Culture Bioreactor

Science.gov (United States)

Freed, Lisa E.; Cheng, Mingyu; Moretti, Matteo G.

2010-01-01

To better exploit the principles of gas transport and mass transport during the processes of cell seeding of 3D scaffolds and in vitro culture of 3D tissue engineered constructs, the oscillatory cell culture bioreactor provides a flow of cell suspensions and culture media directly through a porous 3D scaffold (during cell seeding) and a 3D construct (during subsequent cultivation) within a highly gas-permeable closed-loop tube. This design is simple, modular, and flexible, and its component parts are easy to assemble and operate, and are inexpensive. Chamber volume can be very low, but can be easily scaled up. This innovation is well suited to work with different biological specimens, particularly with cells having high oxygen requirements and/or shear sensitivity, and different scaffold structures and dimensions. The closed-loop changer is highly gas permeable to allow efficient gas exchange during the cell seeding/culturing process. A porous scaffold, which may be seeded with cells, is fixed by means of a scaffold holder to the chamber wall with scaffold/construct orientation with respect to the chamber determined by the geometry of the scaffold holder. A fluid, with/without biological specimens, is added to the chamber such that all, or most, of the air is displaced (i.e., with or without an enclosed air bubble). Motion is applied to the chamber within a controlled environment (e.g., oscillatory motion within a humidified 37 C incubator). Movement of the chamber induces relative motion of the scaffold/construct with respect to the fluid. In case the fluid is a cell suspension, cells will come into contact with the scaffold and eventually adhere to it. Alternatively, cells can be seeded on scaffolds by gel entrapment prior to bioreactor cultivation. Subsequently, the oscillatory cell culture bioreactor will provide efficient gas exchange (i.e., of oxygen and carbon dioxide, as required for viability of metabolically active cells) and controlled levels of fluid

Axenic culture and encapsulation of the intraradical forms of Glomus spp.

Science.gov (United States)

Strullu, D G; Romand, C; Plenchette, C

1991-05-01

In recent years there have been many attempts to cultivate in vitro vesicular-arbuscular mycorrhizal (VAM) fungi which are obligate symbionts. Resting spores extracted from soils are often used as inoculum. Mycorrhizal root pieces are also used for inoculation but the role of intra-radical structures has not been clearly established. On agar medium vegetative mycelium was regenerated from individual intra-radical vesicles and from hyphae extracted by enzymatic maceration. After cell penetration, the mycelium probably accumulates substances which allow growth of VAM fungi in pure culture. When associated with tomato roots, this mycelium forms typical mycorrhizae. Encapsulation stabilized the biological properties of mycorrhizal roots and isolated vesicles. The immobilization also preserved the infectivity of the intra-radical hyphae and vesicles. After 25 years of exclusive utilization of resting spores as starting material for axenic and dual cultures of VAM fungi, it appears that intra-radical vesicles may be preferable propagules.

Conducting Polymer Scaffolds for Hosting and Monitoring 3D Cell Culture

KAUST Repository

Inal, Sahika

2017-05-03

This work reports the design of a live-cell monitoring platform based on a macroporous scaffold of a conducting polymer, poly(3,4-ethylene dioxythiophene):poly(styrenesulfonate). The conducting polymer scaffolds support 3D cell cultures due to their biocompatibility and tissue-like elasticity, which can be manipulated by inclusion of biopolymers such as collagen. Integration of a media perfusion tube inside the scaffold enables homogenous cell spreading and fluid transport throughout the scaffold, ensuring long term cell viability. This also allows for co-culture of multiple cell types inside the scaffold. The inclusion of cells within the porous architecture affects the impedance of the electrically conducting polymer network and, thus, is utilized as an in situ tool to monitor cell growth. Therefore, while being an integral part of the 3D tissue, the conducting polymer is an active component, enhancing the tissue function, and forming the basis for a bioelectronic device with integrated sensing capability.

Functional enhancement of chitosan and nanoparticles in cell culture, tissue engineering, and pharmaceutical applications

Directory of Open Access Journals (Sweden)

Wenjuan eGao

2012-08-01

Full Text Available Abstract: As a biomaterial, chitosan has been widely used in tissue engineering, wound healing, drug delivery, and other biomedical applications. It can be formulated in a variety of forms, such as powder, film, sphere, gel and fiber. These features make chitosan an almost ideal biomaterial in cell culture applications, and cell cultures arguably constitute the most practical way to evaluate biocompatibility and biotoxicity. The advantages of cell cultures are that they can be performed under totally controlled environments, allow high throughput functional screening, and are less costly, as compared to other assessment methods. Chitosan can also be modified into multilayer composite by combining with other polymers and moieties to alter the properties of chitosan for particular biomedical applications. This review briefly depicts and discusses applications of chitosan and nanoparticles in cell culture, in particular, the effects of chitosan and nanoparticles on cell adhesion, cell survival, and the underlying molecular mechanisms: both stimulatory and inhibitory influences are discussed. Our aim is to update the current status of how nanoparticles can be utilized to modify the properties of chitosan to advance the art of tissue engineering by using cell cultures.

Osteoinductive activity of insulin-functionalized cell culture surfaces obtained using diazonium chemistry

Science.gov (United States)

Mikulska, Anna; Filipowska, Joanna; Osyczka, Anna; Nowakowska, Maria; Szczubiałka, Krzysztof

2014-12-01

Polymeric surfaces suitable for cell culture (DR/Pec) were constructed from diazoresin (DR) and pectin (Pec) in a form of ultrathin films using the layer-by-layer (LbL) technique. The surfaces were functionalized with insulin using diazonium chemistry. Such functionalized surfaces were used to culture human mesenchymal stem cells (hMSCs) to assess their suitability for bone tissue engineering and regeneration. The activity of insulin immobilized on the surfaces (DR/Pec/Ins) was compared to that of insulin dissolved in the culture medium. Human MSC grown on insulin-immobilized DR/Pec surfaces displayed increased proliferation and higher osteogenic activity. The latter was determined by means of alkaline phosphatase (ALP) activity, which increases at early stages of osteoblasts differentiation. Insulin dissolved in the culture medium did not stimulate cell proliferation and its osteogenic activity was significantly lower. Addition of recombinant human bone morphogenetic protein 2 (rhBMP-2) to the culture medium further increased ALP activity in hMSCs indicating additive osteogenic action of immobilized insulin and rhBMP-2

Osteoinductive activity of insulin-functionalized cell culture surfaces obtained using diazonium chemistry

Directory of Open Access Journals (Sweden)

Anna eMikulska

2015-01-01

Full Text Available Polymeric surfaces suitable for cell culture (DR/Pec were constructed from diazoresin (DR and pectin (Pec in a form of ultrathin films using the layer-by-layer (LbL technique. The surfaces were functionalized with insulin using diazonium chemistry. Such functionalized surfaces were used to culture human mesenchymal stem cells (hMSCs to assess their suitability for bone tissue engineering and regeneration. The activity of insulin immobilized on the surfaces (DR/Pec/Ins was compared to that of insulin dissolved in the culture medium. Human MSC grown on insulin-immobilized DR/Pec surfaces displayed increased proliferation and higher osteogenic activity. The latter was determined by means of alkaline phosphatase (ALP activity, which increases at early stages of osteoblasts differentiation. Insulin dissolved in the culture medium did not stimulate cell proliferation and its osteogenic activity was significantly lower. Addition of recombinant human bone morphogenetic protein 2 (rhBMP-2 to the culture medium further increased ALP activity in hMSCs indicating additive osteogenic action of immobilized insulin and rhBMP-2

Effects of taurine depletion on cell migration and NCAM expression in cultures of dissociated mouse cerebellum and N2A cells

DEFF Research Database (Denmark)

Maar, T E; Lund, Trine Meldgaard; Gegelashvili, G

1998-01-01

Cultures of dissociated cerebellum from 5- to 6-day-old mice as well as of the N2A neuronal cell line were exposed to guanidino ethane sulfonate (GES, 2-5 mM) to reduce the cellular taurine content. Control cultures were kept in culture medium or medium containing 2-5 mM GES plus 2-5 mM taurine...... to restore the intracellular taurine content. Taurine depletion led to changes in the expression of certain splice variants of NCAM mRNA such as the AAG and the VASE containing forms, while no differences were seen in the expression of the three forms of NCAM protein. In the N2A cells taurine depletion led...... to a decreased migration rate of the cells. The results suggest that the reduced migration rate of neurons caused by taurine depletion may be correlated to changes in expression of certain adhesion molecules such as NCAM. Moreover, taurine appears to be involved in regulation of transcription processes....

Testicular Sertoli cells influence the proliferation and immunogenicity of co-cultured endothelial cells

International Nuclear Information System (INIS)

Fan, Ping; He, Lan; Pu, Dan; Lv, Xiaohong; Zhou, Wenxu; Sun, Yining; Hu, Nan

2011-01-01

Research highlights: → The proliferation of dramatic increased by co-cultured with Sertoli cells. → VEGF receptor-2 expression of ECs was up-regulated by co-cultured with Sertoli cells. → The MHC expression of ECs induced by INF-γ and IL-6, IL-8 and sICAM induced by TNF-α decreased respectively after co-cultured with Sertoli cells. → ECs co-cultured with Sertoli cells also didn't increase the stimulation index of spleen lymphocytes. -- Abstract: The major problem of the application of endothelial cells (ECs) in transplantation is the lack of proliferation and their immunogenicity. In this study, we co-cultured ECs with Sertoli cells to monitor whether Sertoli cells can influence the proliferation and immunogenicity of co-cultured ECs. Sertoli cells were isolated from adult testicular tissue. ECs were divided into the control group and the experimental group, which included three sub-groups co-cultured with 1 x 10 3 , 1 x 10 4 or 1 x 10 5 cell/ml of Sertoli cells. The growth and proliferation of ECs were observed microscopically, and the expression of vascular endothelial growth factor (VEGF) receptor-2 (KDR) was examined by Western blotting. In another experiment, ECs were divided into the control group, the single culture group and the co-culture group with the optimal concentration of Sertoli cells. After INF-γ and TNF-α were added to the culture medium, MHC II antigen expression was detected by immunofluorescence staining and western blotting; interleukin (IL)-6, IL-8 and soluble intercellular adhesion molecule (sICAM) were measured in the culture medium by ELISA. We demonstrated that 1 x 10 4 cell/ml Sertoli cells promoted the proliferation of co-cultured ECs more dramatically than that in other groups (P 4 cell/ml of the Sertoli cells was most effective in the up-regulation of KDR expression in the co-cultured ECs (P < 0.05). Sertoli cells can effectively suppress INF-γ-induced MHC II antigen expression in co-cultured ECs compared with single

Co-culture with podoplanin+ cells protects leukemic blast cells with leukemia-associated antigens in the tumor microenvironment.

Science.gov (United States)

Lee, Ji Yoon; Han, A-Reum; Lee, Sung-Eun; Min, Woo-Sung; Kim, Hee-Je

2016-05-01

Podoplanin+ cells are indispensable in the tumor microenvironment. Increasing evidence suggests that podoplanin may support the growth and metastasis of solid tumors; however, to the best of our knowledge no studies have determined whether or not podoplanin serves a supportive role in acute myeloid leukemia (AML). The effects of co‑culture with podoplanin+ cells on the cellular activities of the leukemic cells, such as apoptosis and cell proliferation, in addition to the expression of podoplanin in leukemic cells, were investigated. Due to the fact that genetic abnormalities are the primary cause of leukemogenesis, the overexpression of the fibromyalgia‑like tyrosine kinase‑3 gene in colony forming units was also examined following cell sorting. Podoplanin+ cells were found to play a protective role against apoptosis in leukemic cells and to promote cell proliferation. Tumor‑associated antigens, including Wilms' tumor gene 1 and survivin, were increased when leukemic cells were co‑cultured with podoplanin+ cells. In combination, the present results also suggest that podoplanin+ cells can function as stromal cells for blast cell retention in the AML tumor microenvironment.

Triple co-culture cell model as an in vitro model for oral particulate vaccine systems

DEFF Research Database (Denmark)

Nielsen, Line Hagner; De Rossi, C.; Lehr, C-M.

; this was not observed with ovalbumin and blank solution. An example of the results is shown in Figure 2 for IL-17A. An established co-culture of Caco-2, THP-1 and MUTZ-3 cells showed promise as an in vitro model for testing of oral vaccine formulations. Mobility of co-culture immune cells as well as cytokine production......A triple co-culture cell model of Caco-2 cells, dendritic cells and macrophages (Figure 1) has previously been developed for studying intestinal permeability in a state of inflammation [1],[2]. The aim of this study was to investigate the applicability of this cell model for testing...... the model antigen ovalbumin was spray dried to obtain a particulate vaccine model system for testing in the cell model. The precursors were shown to form cubosomes when dispersed in aqueous medium, and was therefore used as the vaccine formulation for testing on the co-cultures. After 11 days, the TEER...

Long distance relationships : the secret for fuel cell success? fuel cell developers and integrators form trans-oceanic partnerships to crash through cultural barriers

International Nuclear Information System (INIS)

Horwitz, J.

2009-01-01

The varieties of viable fuel cell applications and widely varying regional market conditions have created global partnerships among entities with complementary attributes. Although it may appear that domestic liaisons among culturally similar players spawned from industry clusters should provide the clearest route to success in this industry, it is the intercontinental groupings which are demonstrating the most potential. This paper discussed the global fuel cell challenge and the vertical integration of multi-national partnerships. The paper also discussed the current global stationary market in perspective. Fuel cells require unique maintenance, support, and refueling including operator instruction and a new supply infrastructure. The paper addressed the fact that fuel cells represent a disruptive technology. A telecom backup status report was also presented. Other topics that were discussed included developing markets as well as specific examples of global organizations such as Canadian Ballard and Danish Dantherm Power and their fuel cell application solutions. It was concluded that after an inconsistent history, fuel cells have finally achieved viability in the real world. However, there is significant cultural resistance to their implementation in the United States. 4 figs

Reconstitution activity of hypoxic cultured human cord blood CD34-positive cells in NOG mice

International Nuclear Information System (INIS)

Shima, Haruko; Takubo, Keiyo; Iwasaki, Hiroko; Yoshihara, Hiroki; Gomei, Yumiko; Hosokawa, Kentaro; Arai, Fumio; Takahashi, Takao; Suda, Toshio

2009-01-01

Hematopoietic stem cells (HSCs) reside in hypoxic areas of the bone marrow. However, the role of hypoxia in the maintenance of HSCs has not been fully characterized. We performed xenotransplantation of human cord blood cells cultured in hypoxic or normoxic conditions into adult NOD/SCID/IL-2Rγ null (NOG) mice. Hypoxic culture (1% O 2 ) for 6 days efficiently supported the maintenance of HSCs, although cell proliferation was suppressed compared to the normoxic culture. In contrast, hypoxia did not affect in vitro colony-forming ability. Upregulation of a cell cycle inhibitor, p21, was observed in hypoxic culture. Immunohistochemical analysis of recipient bone marrow revealed that engrafted CD34 + CD38 - cord blood HSCs were hypoxic. Taken together, these results demonstrate the significance of hypoxia in the maintenance of quiescent human cord blood HSCs.

Long-term culture and differentiation of porcine red bone marrow hematopoietic cells co-cultured with immortalized mesenchymal cells.

Science.gov (United States)

Garba, Abubakar; Acar, Delphine D; Roukaerts, Inge D M; Desmarets, Lowiese M B; Devriendt, Bert; Nauwynck, Hans J

2017-09-01

Mesenchymal cells are multipotent stromal cells with self-renewal, differentiation and immunomodulatory capabilities. We aimed to develop a co-culture model for differentiating hematopoietic cells on top of immortalized mesenchymal cells for studying interactions between hematopoietic and mesenchymal cells, useful for adequately exploring the therapeutic potential of mesenchymal cells. In this study, we investigated the survival, proliferation and differentiation of porcine red bone marrow hematopoietic cells co-cultured with immortalized porcine bone marrow mesenchymal cells for a period of five weeks. Directly after collection, primary porcine bone marrow mesenchymal cells adhered firmly to the bottom of the culture plates and showed a fibroblast-like appearance, one week after isolation. Upon immortalization, porcine bone marrow mesenchymal cells were continuously proliferating. They were positive for simian virus 40 (SV40) large T antigen and the mesenchymal cell markers CD44 and CD55. Isolated red bone marrow cells were added to these immortalized mesenchymal cells. Five weeks post-seeding, 92±6% of the red bone marrow hematopoietic cells were still alive and their number increased 3-fold during five weekly subpassages on top of the immortalized mesenchymal cells. The red bone marrow hematopoietic cells were originally small and round; later, the cells increased in size. Some of them became elongated, while others remained round. Tiny dendrites appeared attaching hematopoietic cells to the underlying immortalized mesenchymal cells. Furthermore, weekly differential-quick staining of the cells indicated the presence of monoblasts, monocytes, macrophages and lymphocytes in the co-cultures. At three weeks of co-culture, flow cytometry analysis showed an increased surface expression of CD172a, CD14, CD163, CD169, CD4 and CD8 up to 37±0.8%, 40±8%, 41±4%, 23±3% and 19±5% of the hematopoietic cells, respectively. In conclusion, continuous mesenchymal cell

Mouse embryonic stem cell culture for generation of three-dimensional retinal and cortical tissues.

Science.gov (United States)

Eiraku, Mototsugu; Sasai, Yoshiki

2011-12-15

Generation of compound tissues with complex structures is a major challenge in cell biology. In this article, we describe a protocol for mouse embryonic stem cell (ESC) culture for in vitro generation of three-dimensional retinal tissue, comparing it with the culture protocol for cortical tissue generation. Dissociated ESCs are reaggregated in a 96-well plate with reduced cell-plate adhesion and cultured as floating aggregates. Retinal epithelium is efficiently generated when ESC aggregates are cultured in serum-free medium containing extracellular matrix proteins, spontaneously forming hemispherical vesicles and then progressively transforming into a shape reminiscent of the embryonic optic cup in 9-10 d. In long-term culture, the ESC-derived optic cup generates a fully stratified retinal tissue consisting of all major neural retinal components. In contrast, the cortical differentiation culture can be started without exogenous extracellular matrix proteins, and it generates stratified cortical epithelia consisting of four distinct layers in 13 d.

Biomaterials in co-culture systems: towards optimizing tissue integration and cell signaling within scaffolds.

Science.gov (United States)

Battiston, Kyle G; Cheung, Jane W C; Jain, Devika; Santerre, J Paul

2014-05-01

Most natural tissues consist of multi-cellular systems made up of two or more cell types. However, some of these tissues may not regenerate themselves following tissue injury or disease without some form of intervention, such as from the use of tissue engineered constructs. Recent studies have increasingly used co-cultures in tissue engineering applications as these systems better model the natural tissues, both physically and biologically. This review aims to identify the challenges of using co-culture systems and to highlight different approaches with respect to the use of biomaterials in the use of such systems. The application of co-culture systems to stimulate a desired biological response and examples of studies within particular tissue engineering disciplines are summarized. A description of different analytical co-culture systems is also discussed and the role of biomaterials in the future of co-culture research are elaborated on. Understanding the complex cell-cell and cell-biomaterial interactions involved in co-culture systems will ultimately lead the field towards biomaterial concepts and designs with specific biochemical, electrical, and mechanical characteristics that are tailored towards the needs of distinct co-culture systems. Copyright © 2014 Elsevier Ltd. All rights reserved.

Advances in cell culture: anchorage dependence

Science.gov (United States)

Merten, Otto-Wilhelm

2015-01-01

Anchorage-dependent cells are of great interest for various biotechnological applications. (i) They represent a formidable production means of viruses for vaccination purposes at very large scales (in 1000–6000 l reactors) using microcarriers, and in the last decade many more novel viral vaccines have been developed using this production technology. (ii) With the advent of stem cells and their use/potential use in clinics for cell therapy and regenerative medicine purposes, the development of novel culture devices and technologies for adherent cells has accelerated greatly with a view to the large-scale expansion of these cells. Presently, the really scalable systems—microcarrier/microcarrier-clump cultures using stirred-tank reactors—for the expansion of stem cells are still in their infancy. Only laboratory scale reactors of maximally 2.5 l working volume have been evaluated because thorough knowledge and basic understanding of critical issues with respect to cell expansion while retaining pluripotency and differentiation potential, and the impact of the culture environment on stem cell fate, etc., are still lacking and require further studies. This article gives an overview on critical issues common to all cell culture systems for adherent cells as well as specifics for different types of stem cells in view of small- and large-scale cell expansion and production processes. PMID:25533097

Development of a cell culture surface conversion technique using alginate thin film for evaluating effect upon cellular differentiation

International Nuclear Information System (INIS)

Nakashima, Y.; Tsusu, K.; Minami, K.; Nakanishi, Y.

2014-01-01

Here, we sought to develop a cell culture surface conversion technique that would not damage living cells. An alginate thin film, formed on a glass plate by spin coating of sodium alginate solution and dipping into calcium chloride solution, was used to inhibit adhesion of cells. The film could be removed by ethylenediaminetetraacetate (EDTA) at any time during cell culture, permitting observation of cellular responses to conversion of the culture surface in real time. Additionally, we demonstrated the validity of the alginate thin film coating method and the performance of the film. The thickness of the alginate thin film was controlled by varying the rotation speed during spin coating. Moreover, the alginate thin film completely inhibited the adhesion of cultured cells to the culture surface, irrespective of the thickness of the film. When the alginate thin film was removed from the culture surface by EDTA, the cultured cells adhered to the culture surface, and their morphology changed. Finally, we achieved effective differentiation of C2C12 myoblasts into myotube cells by cell culture on the convertible culture surface, demonstrating the utility of our novel technique

Effect of primarily cultured human lung cancer-associated fibroblasts on radiosensitivity of lung cancer cells

International Nuclear Information System (INIS)

Ji Xiaoqin; Ji Jiang; Chen Yongbing; Shan Fang; Lu Xueguan

2014-01-01

Objective: To investigate the effect of human lung cancer-associated fibroblasts (CAF) on the radiosensitivity of lung cancer cells when CAF is placed in direct contact co-culture with lung cancer cells. Methods: Human lung CAF was obtained from fresh human lung adenocarcinoma tissue specimens by primary culture and subculture and was then identified by immunofluorescence staining. The CAF was placed in direct contact co-culture with lung cancer A 549 and H 1299 cells, and the effects of CAF on the radiosensitivity of A 549 and H 1299 cells were evaluated by colony-forming assay. Results: The human lung CAF obtained by adherent culture could stably grow and proliferate, and it had specific expression of α-smooth muscle actin, vimentin, and fibroblast activation protein,but without expression of cytokeratin-18. The plating efficiency (PE, %) of A 549 cells at 0 Gy irradiation was (20.0 ± 3.9)% when cultured alone versus (32.3 ± 5.5)% when co-cultured with CAF (t=3.16, P<0.05), and the PE of H 1299 cells at 0 Gy irradiation was (20.6 ± 3.1)% when cultured alone versus (35.2 ± 2.3)% when co-cultured with CAF (t=6.55, P<0.05). The cell survival rate at 2 Gy irradiation (SF 2 ) of A 549 cells was 0.727 ±0.061 when cultured alone versus 0.782 ± 0.089 when co-cultured with CAF (t=0.88, P>0.05), and the SF 2 of H 1299 cells was 0.692 ±0.065 when cultured alone versus 0.782 ± 0.037 when co-cultured with CAF (t=2.08, P>0.05). The protection enhancement ratios of human lung CAF for A 549 cells and H 1299 cells were 1.29 and 1.25, respectively. Conclusions: Human lung CAF reduces the radiosensitivity of lung cancer cells when placed in direct contact co-culture with them, and the radioprotective effect may be attributed to CAF promoting the proliferation of lung cancer cells. (authors)

A simple hanging drop cell culture protocol for generation of 3D spheroids.

Science.gov (United States)

Foty, Ramsey

2011-05-06

Studies of cell-cell cohesion and cell-substratum adhesion have historically been performed on monolayer cultures adherent to rigid substrates. Cells within a tissue, however, are typically encased within a closely packed tissue mass in which cells establish intimate connections with many near-neighbors and with extracellular matrix components. Accordingly, the chemical milieu and physical forces experienced by cells within a 3D tissue are fundamentally different than those experienced by cells grown in monolayer culture. This has been shown to markedly impact cellular morphology and signaling. Several methods have been devised to generate 3D cell cultures including encapsulation of cells in collagen gels or in biomaterial scaffolds. Such methods, while useful, do not recapitulate the intimate direct cell-cell adhesion architecture found in normal tissues. Rather, they more closely approximate culture systems in which single cells are loosely dispersed within a 3D meshwork of ECM products. Here, we describe a simple method in which cells are placed in hanging drop culture and incubated under physiological conditions until they form true 3D spheroids in which cells are in direct contact with each other and with extracellular matrix components. The method requires no specialized equipment and can be adapted to include addition of any biological agent in very small quantities that may be of interest in elucidating effects on cell-cell or cell-ECM interaction. The method can also be used to co-culture two (or more) different cell populations so as to elucidate the role of cell-cell or cell-ECM interactions in specifying spatial relationships between cells. Cell-cell cohesion and cell-ECM adhesion are the cornerstones of studies of embryonic development, tumor-stromal cell interaction in malignant invasion, wound healing, and for applications to tissue engineering. This simple method will provide a means of generating tissue-like cellular aggregates for measurement of

Suspension culture of pluripotent stem cells: effect of shear on stem cell fate.

Science.gov (United States)

Keller, Kevin C; Rodrigues, Beatriz; zur Nieden, Nicole I

2014-01-01

Despite significant promise, the routine usage of suspension cell culture to manufacture stem cell-derived differentiated cells has progressed slowly. Suspension culture is an innovative way of either expanding or differentiating cells and sometimes both are combined into a single bioprocess. Its advantages over static 2D culturing include a homogeneous and controllable culture environment and producing a large quantity of cells in a fraction of time. This feature makes suspension cell culture ideal for use in stem cell research and eventually ideal in the large-scale production of differentiated cells for regenerative medicine. Because of their tremendous differentiation capacities and unlimited growth properties, pluripotent stem cells (PSCs) in particular are considered potential sources for future cell-replacement therapies. Currently, expansion of PSCs is accomplished in 2D, which only permits a limited amount of cell growth per culture flask before cells need to be passaged. However, before stem cells can be applied clinically, several aspects of their expansion, such as directed growth, but also differentiation, need to be better controlled. This review will summarize recent advantages in suspension culture of PSCs, while at the same time highlighting current challenges.

Separation of active and inactive fractions from starved culture of Vibrio parahaemolyticus by density dependent cell sorting.

Science.gov (United States)

Nayak, Binaya Bhusan; Kamiya, Eriko; Nishino, Tomohiko; Wada, Minoru; Nishimura, Masahiko; Kogure, Kazuhiro

2005-01-01

The co-existence of physiologically different cells in bacterial cultures is a general phenomenon. We have examined the applicability of the density dependent cell sorting (DDCS) method to separate subpopulations from a long-term starvation culture of Vibrio parahaemolyticus. The cells were subjected to Percoll density gradient and separated into 12 fractions of different buoyant densities, followed by measuring the cell numbers, culturability, respiratory activity and leucine incorporation activity. While more than 78% of cells were in lighter fractions, about 95% of culturable cells were present in heavier fractions. The high-density subpopulations also had high proportion of cells capable of forming formazan granules. Although this was accompanied by the cell specific INT-reduction rate, both leucine incorporation rates and INT-reduction rates per cell had a peak at mid-density fraction. The present results indicated that DDCS could be used to separate subpopulations of different physiological conditions.

Controlling the diversity of cell populations in a stem cell culture

NARCIS (Netherlands)

Heo, Inha; Clevers, Hans

2015-01-01

Culturing intestinal stem cells into 3D organoids results in heterogeneous cell populations, reflecting the in vivo cell type diversity. In a recent paper published in Nature, Wang et al. established a culture condition for a highly homogeneous population of intestinal stem cells.

Tissue non-specific alkaline phosphatase production by human dental pulp stromal cells is enhanced by high density cell culture.

Science.gov (United States)

Tomlinson, Matthew J; Dennis, Caitriona; Yang, Xuebin B; Kirkham, Jennifer

2015-08-01

The cell surface hydrolase tissue non-specific alkaline phosphatase (TNAP) (also known as MSCA-1) is used to identify a sub-population of bone marrow stromal cells (BMSCs) with high mineralising potential and is found on subsets of cells within the dental pulp. We aim to determine whether TNAP is co-expressed by human dental pulp stromal cells (hDPSCs) alongside a range of BMSC markers, whether this is an active form of the enzyme and the effects of culture duration and cell density on its expression. Cells from primary dental pulp and culture expanded hDPSCs expressed TNAP. Subsequent analyses revealed persistent TNAP expression and co-expression with BMSC markers such as CD73 and CD90. Flow cytometry and biochemical assays showed that increased culture durations and cell densities enhanced TNAP expression by hDPSCs. Arresting the hDPSC cell cycle also increased TNAP expression. These data confirm that TNAP is co-expressed by hDPSCs together with other BMSC markers and show that cell density affects TNAP expression levels. We conclude that TNAP is a potentially useful marker for hDPSC selection especially for uses in mineralised tissue regenerative therapies.

[Formation of protodioscin and deltoside isomers in suspension cultures of Nepal yam (Dioscorea deltoidea Wall.) cells].

Science.gov (United States)

Khandy, M T; Titova, M V; Konstantinova, S V; Kochkin, D V; Ivanov, I M; Nosov, A M

2016-01-01

Changes in the content of the furostanol glycosides protodioscin and deltoside, particularly that of the (25S)-isomers of the glycosides, during suspension cultivation of different lines of Nepal yam (Dioscorea deltoidea Wall.) cells of the strain IFR-DM-0.5 has been investigated. The composition of furostanol glycosides has been characterized, and the dynamics of the accumulation of individual glycosides during lengthy subcultivation of cells maintained in flasks or in a barbotage bioreactor has been analyzed. A positive correlation between the growth and accumulation of substances that belonged to the class of furostanol glycosides has been demonstrated for cultured dioscorea cells, whereas the content of some of the individual glycosides varied considerably between the lines of the strain, cultures maintained under different conditions, and even between cells in different phases of the growth cycle. The increased content of (25R)-forms of the glycosides (protodioscin and deltoside) was correlated with a decrease in the cellular growth rate, whereas an increase in culture growth intensity occurred concomitantly to an increase of the amount of (25S)-isomers. This may be indicative of the specific stimulatory effect of (25S)-glycosides, but not the (25R)-forms, on cell proliferation in vitro. Thus, the concentration of (25S)-forms may increase due to the autoselection of cells capable of intensive division during prolonged cultivation.

The evolution of chicken stem cell culture methods.

Science.gov (United States)

Farzaneh, M; Attari, F; Mozdziak, P E; Khoshnam, S E

2017-12-01

1. The avian embryo is an excellent model for studying embryology and the production of pharmaceutical proteins in transgenic chickens. Furthermore, chicken stem cells have the potential for proliferation and differentiation and emerged as an attractive tool for various cell-based technologies. 2. The objective of these studies is the derivation and culture of these stem cells is the production of transgenic birds for recombinant biomaterials and vaccine manufacture, drug and cytotoxicity testing, as well as to gain insight into basic science, including cell tracking. 3. Despite similarities among the established chicken stem cell lines, fundamental differences have been reported between their culture conditions and applications. Recent conventional protocols used for expansion and culture of chicken stem cells mostly depend on feeder cells, serum-containing media and static culture. 4. Utilising chicken stem cells for generation of cell-based transgenic birds and a variety of vaccines requires large-scale cell production. However, scaling up the conventional adherent chicken stem cells is challenging and labour intensive. Development of a suspension cell culture process for chicken embryonic stem cells (cESCs), chicken primordial germ cells (PGCs) and chicken induced pluripotent stem cells (ciPSCs) will be an important advance for increasing the growth kinetics of these cells. 6. This review describes various approaches and suggestions to achieve optimal cell growth for defined chicken stem cells cultures and use in future manufacturing applications.

Sustained release of stem cell factor in a double network hydrogel for ex vivo culture of cord blood-derived CD34+ cells.

Science.gov (United States)

Zhang, Yuanhao; Pan, Xiuwei; Shi, Zhen; Cai, Haibo; Gao, Yun; Zhang, Weian

2018-04-01

Stem cell factor (SCF) is considered as a commonly indispensable cytokine for proliferation of haematopoietic stem cells (HSCs), which is used in large dosages during ex vivo culture. The work presented here aimed to reduce the consumption of SCF by sustained release but still support cells proliferation and maintain the multipotency of HSCs. Stem cell factor was physically encapsulated within a hyaluronic acid/gelatin double network (HGDN) hydrogel to achieve a slow release rate. CD34 + cells were cultured within the SCF-loaded HGDN hydrogel for 14 days. The cell number, phenotype and functional capacity were investigated after culture. The HGDN hydrogels had desirable properties and encapsulated SCF kept being released for more than 6 days. SCF remained the native bioactivity, and the proliferation of HSCs within the SCF-loaded HGDN hydrogel was not affected, although the consumption of SCF was only a quarter in comparison with the conventional culture. Moreover, CD34 + cells harvested from the SCF-loaded HGDN hydrogels generated more multipotent colony-forming units (CFU-GEMM). The data suggested that the SCF-loaded HGDN hydrogel could support ex vivo culture of HSCs, thus providing a cost-effective culture protocol for HSCs. © 2017 John Wiley & Sons Ltd.

Differential radiosensitivity of mouse embryonic neurons and glia in cell culture

International Nuclear Information System (INIS)

Dambergs, R.; Kidson, C.

1977-01-01

The responses of neurons and glial cells to ultraviolet and γ-radiation were studied in cell cultures of embryonic mouse brains. A decrease in the ratio of glia to neurons occurred after both forms of irradiation. [ 3 H]thymidine labelling followed by autoradiography revealed that all glia were capable of replication, whereas 70 percent of neurons were non-replicating under the conditions of the study. Ultraviolet radiation caused a decrease in the proportion of replicating neurons but did not affect the proportion of replicating glia, whereas γ-radiation caused a decrease in DNA replication in both cell types. Levels of ultraviolet radiation-induced unscheduled DNA synthesis were lower in neurons than in glia. It is concluded that sensitivity to both ionizing and ultraviolet radiation of neurons and glial cells in embryonic brain cultures is determined primarily by the capacity for and state of DNA replication. Neurons which have already reached the stage of terminal differentiation are more resistant than replicating neurons of glial cells

Mammalian Cell Culture Simplified.

Science.gov (United States)

Moss, Robert; Solomon, Sondra

1991-01-01

A tissue culture experiment that does not require elaborate equipment and that can be used to teach sterile technique, the principles of animal cell line maintenance, and the concept of cell growth curves is described. The differences between cancerous and normal cells can be highlighted. The procedure is included. (KR)

Rabbit uterine epithelial cells: Co-culture with spermatozoa

International Nuclear Information System (INIS)

Boice, M.L.

1988-01-01

A primary culture of rabbit uterine epithelial cells was established and their effects on sperm function were examined in vitro. Epithelial cells were isolated from uteri of estrous rabbits and cultured on floating collagen gels in phenol red-free medium supplemented with 5% fetal bovine serum. Light microscopy and keratin staining showed that the epithelial cell population established in culture had morphological characteristics similar to that seen in the intact endometrium. Cells were cultured with 3 H-leucine and uptake of label by cells and its incorporation into cellular and secretory proteins determined. When compared to cells cultured for 24-48 h, incorporation of label into cellular protein was lower at 72-96 h, but secretion increased. Estradiol 17-β did not affect label uptake or incorporation, but did enhance proliferation of cells as judged by total DNA content of the cell population. Analysis of proteins in media by sodium dodecyl sulfate polyacrylamide gel electrophoresis and fluorography suggested that epithelial and stromal cells synthesis proteins that may be secretory in nature during 72-96 h culture. Twenty-nine to thirty-one h after initiation of epithelial cultures, 1-2 x 10 6 sperm were co-incubated with cells and sperm viability, motility, loss of acrosome and fertilizing ability determined

Dynamics of bone marrow-derived endothelial progenitor cell/mesenchymal stem cell interaction in co-culture and its implications in angiogenesis

International Nuclear Information System (INIS)

Aguirre, A.; Planell, J.A.; Engel, E.

2010-01-01

Research highlights: → BM-EPCs and MSCs establish complex, self-organizing structures in co-culture. → Co-culture decreases proliferation by cellular self-regulatory mechanisms. → Co-cultured cells present an activated proangiogenic phenotype. → qRT-PCR and cluster analysis identify new target genes playing important roles. -- Abstract: Tissue engineering aims to regenerate tissues and organs by using cell and biomaterial-based approaches. One of the current challenges in the field is to promote proper vascularization in the implant to prevent cell death and promote host integration. Bone marrow endothelial progenitor cells (BM-EPCs) and mesenchymal stem cells (MSCs) are bone marrow resident stem cells widely employed for proangiogenic applications. In vivo, they are likely to interact frequently both in the bone marrow and at sites of injury. In this study, the physical and biochemical interactions between BM-EPCs and MSCs in an in vitro co-culture system were investigated to further clarify their roles in vascularization. BM-EPC/MSC co-cultures established close cell-cell contacts soon after seeding and self-assembled to form elongated structures at 3 days. Besides direct contact, cells also exhibited vesicle transport phenomena. When co-cultured in Matrigel, tube formation was greatly enhanced even in serum-starved, growth factor free medium. Both MSCs and BM-EPCs contributed to these tubes. However, cell proliferation was greatly reduced in co-culture and morphological differences were observed. Gene expression and cluster analysis for wide panel of angiogenesis-related transcripts demonstrated up-regulation of angiogenic markers but down-regulation of many other cytokines. These data suggest that cross-talk occurs in between BM-EPCs and MSCs through paracrine and direct cell contact mechanisms leading to modulation of the angiogenic response.

Programmed cell death of tobacco BY-2 cells induced by still culture conditions is affected by the age of the culture under agitation.

Science.gov (United States)

Hiraga, Asahi; Kaneta, Tsuyoshi; Sato, Yasushi; Sato, Seiichi

2010-01-25

Evans Blue staining indicated that actively growing tobacco BY-2 cells in the exponential phase died more rapidly than quiescent cells in the stationary phase when the cells cultured under agitation were placed under still conditions. Fifty percent cell death was induced at about 18, 26, 80 and 140 h for early, mid, late exponential- and stationary-phase cells, respectively. Actively growing cells became TUNEL (transferase-mediated dUTP nick end labelling)-positive more rapidly than quiescent cells, suggesting that the cell death evaluated by Evans Blue is accompanied by DNA cleavages. Electrophoresis of genomic DNA showed a typical 'DNA laddering' pattern formed by multiples of about 200 bp internucleosomal units. Chromatin condensation was first detected at least within 24 h by light microscopy, and then cell shrinkage followed. These findings suggest that the death of BY-2 cells induced by still conditions is PCD (programmed cell death).

X-ray microanalysis of single and cultured cells

International Nuclear Information System (INIS)

Wroblewski, J.; Roomans, G.M.

1984-01-01

X-ray microanalysis of single or cultured cells is often a useful alternative or complement to the analysis of the corresponding tissue. It also allows the analysis of individual cells in a cell population. Preparation for X-ray microanalysis poses a number of typical problems. Suspensions of single cells can be prepared by either of two pathways: (1) washing - mounting - drying, or (2) centrifugation - freezing or fixation - sectioning. The washing step in the preparation of single or cultured cells presents the most severe problems. Cultured cells are generally grown on a substrate that is compatible with both the analysis and the culture, washed and dried. In some cases, sectioning of cultured cell monolayers has been performed. Special problems in quantitative analysis occur in those cases where the cells are analyzed on a thick substrate, since the substrate contributes to the spectral background

Isolation, culture expansion and characterization of canine bone marrow derived mesenchymal stem cells

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D Kazemi

2016-07-01

Full Text Available The purpose of the present study was to isolate, culture expand and characterize canine bone marrow derived mesenchymal stem cells. Bone marrow aspirates of 15 adult male dogs were collected to this end and their mononuclear cells isolated by centrifugation and cultured in standard media. The adherent cells were isolated and their mesenchymal origin was confirmed at 3rd passage by cellular morphology, expression of surface antigens and differentiation to osteogenic and adipogenic lineage. After 4 days, spindle shaped fibroblast like cells which were apparently bone marrow derived mesenchymal stem cells appeared in culture medium and their numbers increased over time. The cells reached 3rd passage with over 75% confluent after a mean of 22.89±5.75 days. Flow cytometric analysis revealed that the cells negatively expressed CD34 and CD45 antigens while positively expressing CD44 and CD105 antigens. Differentiation into osteogenic and adipogenic lineage had taken place after one month culture in induction medium. VDR, COL1A1, BGLAP and SPARC gene expression indicated that mesenchymal stem cells isolated from canine bone marrow had differentiated into osteogenic lineage. These findings can form the basis of any forthcoming clinical studies involving the use of canine mesenchymal stem cells particularly in the field of bone and cartilage regeneration.

Drug and radiation sensitivity measurements of successful primary monolayer culturing of human tumor cells using cell-adhesive matrix and supplemented medium

International Nuclear Information System (INIS)

Baker, F.L.; Spitzer, G.; Ajani, J.A.

1986-01-01

The limitations of the agar suspension culture method for primary culturing of human tumor cells prompted development of a monolayer system optimized for cell adhesion and growth. This method grew 83% of fresh human tumor cell biopsy specimens, cultured and not contaminated, from a heterogeneous group of 396 tumors including lung cancer (93 of 114, 82%); melanoma (54 of 72, 75%); sarcoma (46 of 59, 78%); breast cancer (35 of 39, 90%); ovarian cancer (16 of 21, 76%); and a miscellaneous group consisting of gastrointestinal, genitourinary, mesothelioma, and unknown primaries (78 of 91, 86%). Cell growth was characterized morphologically with Papanicolaoustained coverslip cultures and cytogenetically with Giemsastained metaphase spreads. Morphological features such as nuclear pleomorphism, chromatin condensation, basophilic cytoplasm, and melanin pigmentation were routinely seen. Aneuploid metaphases were seen in 90% of evaluable cultures, with 15 of 28 showing 70% or more aneuploid metaphases. Colony-forming efficiency ranged between 0.01 and 1% of viable tumor cells, with a median efficiency of 0.2%. This culture system uses a low inoculum of 25,000 viable cells per well which permitted chemosensitivity testing of nine drugs at four doses in duplicate from 2.2 X 10(6) viable tumor cells and radiation sensitivity testing at five doses in quadruplicate from 0.6 X 10(6) cells. Cultures were analyzed for survival by computerized image analysis of crystal violet-stained cells. Drug sensitivity studies showed variability in sensitivity and in survival curve shape with exponential cell killing for cisplatin, Adriamycin, and etoposide, and shouldered survival curves for 5-fluorouracil frequently seen. Radiation sensitivity studies also showed variability in both sensitivity and survival curve shape. Many cultures showed exponential cell killing, although others had shouldered survival curves

Three-dimensional Huh7 cell culture system for the study of Hepatitis C virus infection

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Uprichard Susan L

2009-07-01

Full Text Available Abstract Background In order to elucidate how Hepatitis C Virus (HCV interacts with polarized hepatocytes in vivo and how HCV-induced alterations in cellular function contribute to HCV-associated liver disease, a more physiologically relevant hepatocyte culture model is needed. As such, NASA-engineered three-dimensional (3-D rotating wall vessel (RWV bioreactors were used in effort to promote differentiation of HCV-permissive Huh7 hepatoma cells. Results When cultured in the RWV, Huh7 cells became morphologically and transcriptionally distinct from more standard Huh7 two-dimensional (2-D monolayers. Specifically, RWV-cultured Huh7 cells formed complex, multilayered 3-D aggregates in which Phase I and Phase II xenobiotic drug metabolism genes, as well as hepatocyte-specific transcripts (HNF4α, Albumin, TTR and α1AT, were upregulated compared to 2-D cultured Huh7 cells. Immunofluorescence analysis revealed that these HCV-permissive 3-D cultured Huh7 cells were more polarized than their 2D counterparts with the expression of HCV receptors, cell adhesion and tight junction markers (CD81, scavenger receptor class B member 1, claudin-1, occludin, ZO-1, β-Catenin and E-Cadherin significantly increased and exhibiting apical, lateral and/or basolateral localization. Conclusion These findings show that when cultured in 3-D, Huh7 cells acquire a more differentiated hepatocyte-like phenotype. Importantly, we show that these 3D cultures are highly permissive for HCV infection, thus providing an opportunity to study HCV entry and the effects of HCV infection on host cell function in a more physiologically relevant cell culture system.

Dynamic 3D culture promotes spontaneous embryonic stem cell differentiation in vitro.

Science.gov (United States)

Gerlach, Jörg C; Hout, Mariah; Edsbagge, Josefina; Björquist, Petter; Lübberstedt, Marc; Miki, Toshio; Stachelscheid, Harald; Schmelzer, Eva; Schatten, Gerald; Zeilinger, Katrin

2010-02-01

Spontaneous in vitro differentiation of mouse embryonic stem cells (mESC) is promoted by a dynamic, three-dimensional (3D), tissue-density perfusion technique with continuous medium perfusion and exchange in a novel four-compartment, interwoven capillary bioreactor. We compared ectodermal, endodermal, and mesodermal immunoreactive tissue structures formed by mESC at culture day 10 with mouse fetal tissue development at gestational day E9.5. The results show that the bioreactor cultures more closely resemble mouse fetal tissue development at gestational day E9.5 than control mESC cultured in Petri dishes.

Particle Trajectories in Rotating Wall Cell Culture Devices

Science.gov (United States)

Ramachandran N.; Downey, J. P.

1999-01-01

Cell cultures are extremely important to the medical community since such cultures provide an opportunity to perform research on human tissue without the concerns inherent in experiments on individual humans. Development of cells in cultures has been found to be greatly influenced by the conditions of the culture. Much work has focused on the effect of the motions of cells in the culture relative to the solution. Recently rotating wall vessels have been used with success in achieving improved cellular cultures. Speculation and limited research have focused on the low shear environment and the ability of rotating vessels to keep cells suspended in solution rather than floating or sedimenting as the primary reasons for the improved cellular cultures using these devices. It is widely believed that the cultures obtained using a rotating wall vessel simulates to some degree the effect of microgravity on cultures. It has also been speculated that the microgravity environment may provide the ideal acceleration environment for culturing of cellular tissues due to the nearly negligible levels of sedimentation and shear possible. This work predicts particle trajectories of cells in rotating wall vessels of cylindrical and annular design consistent with the estimated properties of typical cellular cultures. Estimates of the shear encountered by cells in solution and the interactions with walls are studied. Comparisons of potential experiments in ground and microgravity environments are performed.

Usability and Applicability of Microfluidic Cell Culture Systems

DEFF Research Database (Denmark)

Hemmingsen, Mette

possibilities for, for example, precise control of the chemical environment, 3D cultures, controlled co-culture of different cell types or automated, individual control of up to 96 cell culture chambers in one integrated system. Despite the great new opportunities to perform novel experimental designs......Microfluidic cell culture has been a research area with great attention the last decade due to its potential to mimic the in vivo cellular environment more closely compared to what is possible by conventional cell culture methods. Many exciting and complex devices have been presented providing......, these devices still lack general implementation into biological research laboratories. In this project, the usability and applicability of microfluidic cell culture systems have been investigated. The tested systems display good properties regarding optics and compatibility with standard laboratory equipment...

Primary Culture of Choroid Plexuses from Neonate Rats Containing Progenitor Cells Capable of Differentiation

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Sheng-Li Huang

2013-12-01

Full Text Available Background: The choroid plexuses, which could secrete a number of neurotrophins, have recently been used in transplantation in central nervous system diseases. Aims: To study the mechanism of nerve regeneration in the central nervous system by grafting choroid plexus tissues. Study Design: Animal experimentation. Methods: The choroid plexuses from the lateral ventricles of neonatal rats were cultured in adherent culture, and immunocytochemical methods were used to analyse the progenitor cells on days 2, 6, and 10 after seeding. Results: Expression of both nestin and glial fibrillary acidic protein was observed in small cell aggregates on day 2 in primary culture. Most of the nestin-positive cells on day 6 were immunoreactive to glial fibrillary acidic protein antibody. No cells expressing nestin or glial fibrillary acidic protein were seen on day 10. Conclusion: These experimental results indicate that the choroid plexus contains a specific cell population – progenitor cells. Under in vitro experimental conditions, the progenitor cells differentiated into choroid plexus epithelial cells but did not form neurons or astrocytes.

Good Cell Culture Practice for stem cells and stem-cell-derived models.

Science.gov (United States)

Pamies, David; Bal-Price, Anna; Simeonov, Anton; Tagle, Danilo; Allen, Dave; Gerhold, David; Yin, Dezhong; Pistollato, Francesca; Inutsuka, Takashi; Sullivan, Kristie; Stacey, Glyn; Salem, Harry; Leist, Marcel; Daneshian, Mardas; Vemuri, Mohan C; McFarland, Richard; Coecke, Sandra; Fitzpatrick, Suzanne C; Lakshmipathy, Uma; Mack, Amanda; Wang, Wen Bo; Yamazaki, Daiju; Sekino, Yuko; Kanda, Yasunari; Smirnova, Lena; Hartung, Thomas

2017-01-01

The first guidance on Good Cell Culture Practice (GCCP) dates back to 2005. This document expands this to include aspects of quality assurance for in vitro cell culture focusing on the increasingly diverse cell types and culture formats used in research, product development, testing and manufacture of biotechnology products and cell-based medicines. It provides a set of basic principles of best practice that can be used in training new personnel, reviewing and improving local procedures, and helping to assure standard practices and conditions for the comparison of data between laboratories and experimentation performed at different times. This includes recommendations for the documentation and reporting of culture conditions. It is intended as guidance to facilitate the generation of reliable data from cell culture systems, and is not intended to conflict with local or higher level legislation or regulatory requirements. It may not be possible to meet all recommendations in this guidance for practical, legal or other reasons. However, when it is necessary to divert from the principles of GCCP, the risk of decreasing the quality of work and the safety of laboratory staff should be addressed and any conclusions or alternative approaches justified. This workshop report is considered a first step toward a revised GCCP 2.0.

Phenotypic characterization of prostate cancer LNCaP cells cultured within a bioengineered microenvironment.

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Shirly Sieh

Full Text Available Biophysical and biochemical properties of the microenvironment regulate cellular responses such as growth, differentiation, morphogenesis and migration in normal and cancer cells. Since two-dimensional (2D cultures lack the essential characteristics of the native cellular microenvironment, three-dimensional (3D cultures have been developed to better mimic the natural extracellular matrix. To date, 3D culture systems have relied mostly on collagen and Matrigel™ hydrogels, allowing only limited control over matrix stiffness, proteolytic degradability, and ligand density. In contrast, bioengineered hydrogels allow us to independently tune and systematically investigate the influence of these parameters on cell growth and differentiation. In this study, polyethylene glycol (PEG hydrogels, functionalized with the Arginine-glycine-aspartic acid (RGD motifs, common cell-binding motifs in extracellular matrix proteins, and matrix metalloproteinase (MMP cleavage sites, were characterized regarding their stiffness, diffusive properties, and ability to support growth of androgen-dependent LNCaP prostate cancer cells. We found that the mechanical properties modulated the growth kinetics of LNCaP cells in the PEG hydrogel. At culture periods of 28 days, LNCaP cells underwent morphogenic changes, forming tumor-like structures in 3D culture, with hypoxic and apoptotic cores. We further compared protein and gene expression levels between 3D and 2D cultures upon stimulation with the synthetic androgen R1881. Interestingly, the kinetics of R1881 stimulated androgen receptor (AR nuclear translocation differed between 2D and 3D cultures when observed by immunofluorescent staining. Furthermore, microarray studies revealed that changes in expression levels of androgen responsive genes upon R1881 treatment differed greatly between 2D and 3D cultures. Taken together, culturing LNCaP cells in the tunable PEG hydrogels reveals differences in the cellular responses to

Long-term maintenance of human induced pluripotent stem cells by automated cell culture system.

Science.gov (United States)

Konagaya, Shuhei; Ando, Takeshi; Yamauchi, Toshiaki; Suemori, Hirofumi; Iwata, Hiroo

2015-11-17

Pluripotent stem cells, such as embryonic stem cells and induced pluripotent stem (iPS) cells, are regarded as new sources for cell replacement therapy. These cells can unlimitedly expand under undifferentiated conditions and be differentiated into multiple cell types. Automated culture systems enable the large-scale production of cells. In addition to reducing the time and effort of researchers, an automated culture system improves the reproducibility of cell cultures. In the present study, we newly designed a fully automated cell culture system for human iPS maintenance. Using an automated culture system, hiPS cells maintained their undifferentiated state for 60 days. Automatically prepared hiPS cells had a potency of differentiation into three germ layer cells including dopaminergic neurons and pancreatic cells.

High-Throughput Cancer Cell Sphere Formation for 3D Cell Culture.

Science.gov (United States)

Chen, Yu-Chih; Yoon, Euisik

2017-01-01

Three-dimensional (3D) cell culture is critical in studying cancer pathology and drug response. Though 3D cancer sphere culture can be performed in low-adherent dishes or well plates, the unregulated cell aggregation may skew the results. On contrary, microfluidic 3D culture can allow precise control of cell microenvironments, and provide higher throughput by orders of magnitude. In this chapter, we will look into engineering innovations in a microfluidic platform for high-throughput cancer cell sphere formation and review the implementation methods in detail.

In vitro induction of alkaline phosphatase levels predicts in vivo bone forming capacity of human bone marrow stromal cells

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Henk-Jan Prins

2014-03-01

Full Text Available One of the applications of bone marrow stromal cells (BMSCs that are produced by ex vivo expansion is for use in in vivo bone tissue engineering. Cultured stromal cells are a mixture of cells at different stages of commitment and expansion capability, leading to a heterogeneous cell population that each time can differ in the potential to form in vivo bone. A parameter that predicts for in vivo bone forming capacity is thus far lacking. We employed single colony-derived BMSC cultures to identify such predictive parameters. Using limiting dilution, we have produced sixteen single CFU-F derived BMSC cultures from human bone marrow and found that only five of these formed bone in vivo. The single colony-derived BMSC strains were tested for proliferation, osteogenic-, adipogenic- and chondrogenic differentiation capacity and the expression of a variety of associated markers. The only robust predictors of in vivo bone forming capacity were the induction of alkaline phosphatase, (ALP mRNA levels and ALP activity during in vitro osteogenic differentiation. The predictive value of in vitro ALP induction was confirmed by analyzing “bulk-cultured” BMSCs from various bone marrow biopsies. Our findings show that in BMSCs, the additional increase in ALP levels over basal levels during in vitro osteogenic differentiation is predictive of in vivo performance.

Liver Cell Culture Devices

NARCIS (Netherlands)

Andria, B.; Bracco, A.; Cirino, G.; Chamuleau, R. A. F. M.

2010-01-01

In the last 15 years many different liver cell culture devices, consisting of functional liver cells and artificial materials, have been developed. They have been devised for numerous different applications, such as temporary organ replacement (a bridge to liver transplantation or native liver

Characterization of glucocerebrosidase in peripheral blood cells and cultured blastoid cells

NARCIS (Netherlands)

Aerts, J. M.; Heikoop, J.; van Weely, S.; Donker-Koopman, W. E.; Barranger, J. A.; Tager, J. M.; Schram, A. W.

1988-01-01

We have characterized glucocerebrosidase in various cell types of peripheral blood of control subjects and in cultured human blastoid cells. The intracellular level of glucocerebrosidase in cultured blastoid cells (10-30 nmol substrate hydrolyzed/h.mg protein) resembles closely values observed for

Metabolism of pharmaceutical and personal care products by carrot cell cultures

International Nuclear Information System (INIS)

Wu, Xiaoqin; Fu, Qiuguo; Gan, Jay

2016-01-01

With the increasing use of treated wastewater and biosolids in agriculture, residues of pharmaceutical and personal care products (PPCPs) in these reused resources may contaminate food produce via plant uptake, constituting a route for human exposure. Although various PPCPs have been reported to be taken up by plants in laboratories or under field conditions, at present little information is available on their metabolism in plants. In this study, we applied carrot cell cultures to investigate the plant metabolism of PPCPs. Five phase I metabolites of carbamazepine were identified and the potential metabolism pathways of carbamazepine were proposed. We also used the carrot cell cultures as a rapid screening tool to initially assess the metabolism potentials of 18 PPCPs. Eleven PPCPs, including acetaminophen, caffeine, meprobamate, primidone, atenolol, trimethoprim, DEET, carbamazepine, dilantin, diazepam, and triclocarban, were found to be recalcitrant to metabolism. The other 7 PPCPs, including triclosan, naproxen, diclofenac, ibuprofen, gemfibrozil, sulfamethoxazole, and atorvastatin, displayed rapid metabolism, with 0.4–47.3% remaining in the culture at the end of the experiment. Further investigation using glycosidase hydrolysis showed that 1.3–20.6% of initially spiked naproxen, diclofenac, ibuprofen, and gemfibrozil were transformed into glycoside conjugates. Results from this study showed that plant cell cultures may be a useful tool for initially exploring the potential metabolites of PPCPs in plants as well as for rapidly screening the metabolism potentials of a variety of PPCPs or other emerging contaminants, and therefore may be used for prioritizing compounds for further comprehensive evaluations. - Highlights: • Five phase I metabolites of carbamazepine were identified in carrot cell cultures. • The metabolism potentials of 18 PPCPs were evaluated using carrot cell cultures. • Four PPCPs may partially form glycoside conjugates as phase II

Direct induction of chondrogenic cells from human dermal fibroblast culture by defined factors.

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Hidetatsu Outani

Full Text Available The repair of large cartilage defects with hyaline cartilage continues to be a challenging clinical issue. We recently reported that the forced expression of two reprogramming factors (c-Myc and Klf4 and one chondrogenic factor (SOX9 can induce chondrogenic cells from mouse dermal fibroblast culture without going through a pluripotent state. We here generated induced chondrogenic (iChon cells from human dermal fibroblast (HDF culture with the same factors. We developed a chondrocyte-specific COL11A2 promoter/enhancer lentiviral reporter vector to select iChon cells. The human iChon cells expressed marker genes for chondrocytes but not fibroblasts, and were derived from non-chondrogenic COL11A2-negative cells. The human iChon cells formed cartilage but not tumors in nude mice. This approach could lead to the preparation of cartilage directly from skin in human, without going through pluripotent stem cells.

Advantages and challenges of microfluidic cell culture in polydimethylsiloxane devices.

Science.gov (United States)

Halldorsson, Skarphedinn; Lucumi, Edinson; Gómez-Sjöberg, Rafael; Fleming, Ronan M T

2015-01-15

Culture of cells using various microfluidic devices is becoming more common within experimental cell biology. At the same time, a technological radiation of microfluidic cell culture device designs is currently in progress. Ultimately, the utility of microfluidic cell culture will be determined by its capacity to permit new insights into cellular function. Especially insights that would otherwise be difficult or impossible to obtain with macroscopic cell culture in traditional polystyrene dishes, flasks or well-plates. Many decades of heuristic optimization have gone into perfecting conventional cell culture devices and protocols. In comparison, even for the most commonly used microfluidic cell culture devices, such as those fabricated from polydimethylsiloxane (PDMS), collective understanding of the differences in cellular behavior between microfluidic and macroscopic culture is still developing. Moving in vitro culture from macroscopic culture to PDMS based devices can come with unforeseen challenges. Changes in device material, surface coating, cell number per unit surface area or per unit media volume may all affect the outcome of otherwise standard protocols. In this review, we outline some of the advantages and challenges that may accompany a transition from macroscopic to microfluidic cell culture. We focus on decisive factors that distinguish macroscopic from microfluidic cell culture to encourage a reconsideration of how macroscopic cell culture principles might apply to microfluidic cell culture. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

Teratoma formation of human embryonic stem cells in three-dimensional perfusion culture bioreactors.

Science.gov (United States)

Stachelscheid, H; Wulf-Goldenberg, A; Eckert, K; Jensen, J; Edsbagge, J; Björquist, P; Rivero, M; Strehl, R; Jozefczuk, J; Prigione, A; Adjaye, J; Urbaniak, T; Bussmann, P; Zeilinger, K; Gerlach, J C

2013-09-01

Teratoma formation in mice is today the most stringent test for pluripotency that is available for human pluripotent cells, as chimera formation and tetraploid complementation cannot be performed with human cells. The teratoma assay could also be applied for assessing the safety of human pluripotent cell-derived cell populations intended for therapeutic applications. In our study we examined the spontaneous differentiation behaviour of human embryonic stem cells (hESCs) in a perfused 3D multi-compartment bioreactor system and compared it with differentiation of hESCs and human induced pluripotent cells (hiPSCs) cultured in vitro as embryoid bodies and in vivo in an experimental mouse model of teratoma formation. Results from biochemical, histological/immunohistological and ultrastuctural analyses revealed that hESCs cultured in bioreactors formed tissue-like structures containing derivatives of all three germ layers. Comparison with embryoid bodies and the teratomas revealed a high degree of similarity of the tissues formed in the bioreactor to these in the teratomas at the histological as well as transcriptional level, as detected by comparative whole-genome RNA expression profiling. The 3D culture system represents a novel in vitro model that permits stable long-term cultivation, spontaneous multi-lineage differentiation and tissue formation of pluripotent cells that is comparable to in vivo differentiation. Such a model is of interest, e.g. for the development of novel cell differentiation strategies. In addition, the 3D in vitro model could be used for teratoma studies and pluripotency assays in a fully defined, controlled environment, alternatively to in vivo mouse models. Copyright © 2012 John Wiley & Sons, Ltd.

Isolation and culture of larval cells from C. elegans.

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Sihui Zhang

Full Text Available Cell culture is an essential tool to study cell function. In C. elegans the ability to isolate and culture cells has been limited to embryonically derived cells. However, cells or blastomeres isolated from mixed stage embryos terminally differentiate within 24 hours of culture, thus precluding post-embryonic stage cell culture. We have developed an efficient and technically simple method for large-scale isolation and primary culture of larval-stage cells. We have optimized the treatment to maximize cell number and minimize cell death for each of the four larval stages. We obtained up to 7.8×10(4 cells per microliter of packed larvae, and up to 97% of adherent cells isolated by this method were viable for at least 16 hours. Cultured larval cells showed stage-specific increases in both cell size and multinuclearity and expressed lineage- and cell type-specific reporters. The majority (81% of larval cells isolated by our method were muscle cells that exhibited stage-specific phenotypes. L1 muscle cells developed 1 to 2 wide cytoplasmic processes, while L4 muscle cells developed 4 to 14 processes of various thicknesses. L4 muscle cells developed bands of myosin heavy chain A thick filaments at the cell center and spontaneously contracted ex vivo. Neurons constituted less than 10% of the isolated cells and the majority of neurons developed one or more long, microtubule-rich protrusions that terminated in actin-rich growth cones. In addition to cells such as muscle and neuron that are high abundance in vivo, we were also able to isolate M-lineage cells that constitute less than 0.2% of cells in vivo. Our novel method of cell isolation extends C. elegans cell culture to larval developmental stages, and allows use of the wealth of cell culture tools, such as cell sorting, electrophysiology, co-culture, and high-resolution imaging of subcellular dynamics, in investigation of post-embryonic development and physiology.

Forming health culture as part of general education

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Andreeva Irina

2016-01-01

Full Text Available The paper outlines methods of forming health culture in the content of education as a theoretical-methodological area aimed at fostering a positive attitude, sustained motivation for health and personal responsibility for its preservation.

Antioxidant effect of thiazolidine molecules in cell culture media improves stability and performance.

Science.gov (United States)

Kuschelewski, Jennifer; Schnellbaecher, Alisa; Pering, Sascha; Wehsling, Maria; Zimmer, Aline

2017-05-01

The ability of cell culture media components to generate reactive species as well as their sensitivity to oxidative degradation, affects the overall stability of media and the behavior of cells cultured in vitro. This study investigates the influence of thiazolidine molecules, formed from the condensation between cysteine and alpha-ketoacids, on the stability of these complex mixtures and on the performance of cell culture processes aiming to produce therapeutically relevant monoclonal antibodies. Results presented in this study indicate that 2-methyl-1,3-thiazolidine-2,4-dicarboxylic acid and 2-(2-carboxyethyl)-1,3-thiazolidine-2,4-dicarboxylic acid, obtained by condensation of cysteine with pyruvate or alpha-ketoglutarate, respectively, are able to stabilize cell culture media formulations, in particular redox sensitive molecules like folic acid, thiamine, l-methionine (met) and l-tryptophan (trp). The use of thiazolidine containing feeds in Chinese hamster ovary fed-batch processes showed prolonged culture duration and increased productivity. This enhanced performance was correlated with lower reactive species generation, extracellularly and intracellularly. Moreover, an anti-oxidative response was triggered via the induction of superoxide dismutase and an increase in the total glutathione pool, the major intracellular antioxidant. In total, the results confirm that cells in vitro are not cultured in an oxidant-free environment, a concept that has to be considered when studying the influence of reactive species in human diseases. Furthermore, this study indicates that thiazolidines are an interesting class of antioxidant molecules, capable of increasing cell culture media stability and process performance. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:759-770, 2017. © 2017 American Institute of Chemical Engineers.

Introducing Mammalian Cell Culture and Cell Viability Techniques in the Undergraduate Biology Laboratory.

Science.gov (United States)

Bowey-Dellinger, Kristen; Dixon, Luke; Ackerman, Kristin; Vigueira, Cynthia; Suh, Yewseok K; Lyda, Todd; Sapp, Kelli; Grider, Michael; Crater, Dinene; Russell, Travis; Elias, Michael; Coffield, V McNeil; Segarra, Verónica A

2017-01-01

Undergraduate students learn about mammalian cell culture applications in introductory biology courses. However, laboratory modules are rarely designed to provide hands-on experience with mammalian cells or teach cell culture techniques, such as trypsinization and cell counting. Students are more likely to learn about cell culture using bacteria or yeast, as they are typically easier to grow, culture, and manipulate given the equipment, tools, and environment of most undergraduate biology laboratories. In contrast, the utilization of mammalian cells requires a dedicated biological safety cabinet and rigorous antiseptic techniques. For this reason, we have devised a laboratory module and method herein that familiarizes students with common cell culture procedures, without the use of a sterile hood or large cell culture facility. Students design and perform a time-efficient inquiry-based cell viability experiment using HeLa cells and tools that are readily available in an undergraduate biology laboratory. Students will become familiar with common techniques such as trypsinizing cells, cell counting with a hemocytometer, performing serial dilutions, and determining cell viability using trypan blue dye. Additionally, students will work with graphing software to analyze their data and think critically about the mechanism of death on a cellular level. Two different adaptations of this inquiry-based lab are presented-one for non-biology majors and one for biology majors. Overall, these laboratories aim to expose students to mammalian cell culture and basic techniques and help them to conceptualize their application in scientific research.

Morphology of primary human venous endothelial cell cultures before and after culture medium exchange.

Science.gov (United States)

Krüger-Genge, A; Fuhrmann, R; Jung, F; Franke, R P

2015-01-01

The evaluation of the interaction of human, venous endothelial cells (HUVEC) with body foreign materials on the cellular level cannot be performed in vivo, but is investigated in vitro under standard culture conditions. To maintain the vitality, proliferation and morphology of HUVEC seeded on body foreign substrates over days, the cell culture medium is usually exchanged every second day. It is well known, that alterations in the microenvironment of cells bear the risk of influencing cell morphology and function. In the current study the influence of cell culture medium exchange on HUVEC cytoskeletal microfilament structure and function was investigated. HUVEC in the third passage were seeded on extracellular matrix (ECM) - which was secreted from bovine corneal endothelial cells on glass- until functional confluence was reached. The experiment started 11 days after HUVEC seeding with an exchange of the cell culture medium followed by a staining of the actin microfilaments with phalloidin-rhodamin 1.5 and 5 minutes after medium exchange. The microfilaments were documented by use of an Olympus microscope (IMT-2) equipped with a UV lamp and online connected to a TV chain (Sony XC 50 ST/monochrome) implying an OPTIMAS - Image analysis system. Prostacyclin was analysed in the cell culture supernatant. 1.5 min after culture medium exchange in the functionally confluent cultures a slight disturbance of the actin microfilament structure with a broadening of the marginal filament band, a partial disconnection of cell-cell contacts and the appearance of intercellular fenestrations were observed. 5 minutes after medium exchange a redevelopment of the slightly disturbed microfilament structure with a condensation and narrowing of the marginal filament band was seen. 12 h later a further consolidation of the microfilament structure occurred. In addition, a perturbation of the cultured HUVEC occurred after cell culture medium exchange. The prostacyclin concentration in the

Clonal distribution of osteoprogenitor cells in cultured chick periostea: Functional relationship to bone formation

International Nuclear Information System (INIS)

McCulloch, C.A.; Fair, C.A.; Tenenbaum, H.C.; Limeback, H.; Homareau, R.

1990-01-01

Folded explants of periosteum from embryonic chick calvaria form bone-like tissue when grown in the presence of ascorbic acid, organic phosphate, and dexamethasone. All osteoblast-like cells in these cultures arise de novo by differentiation of osteoprogenitor cells present in the periosteum. To study the spatial and functional relationships between bone formation and osteoprogenitor cells, cultures were continuously labeled with [3H]thymidine for periods of 1-5 days. Radioautographs of serial 2-microns plastic sections stained for alkaline phosphatase (AP) showed maximal labeling of 30% of fibroblastic (AP-negative) cells by 3 days while osteogenic cells (AP-positive) exhibited over 95% labeling by 5 days. No differential shifts in labeling indices, grain count histograms of fibroblastic and osteogenic cells or numbers of AP-positive cells were observed, indicating no significant recruitment of cells from the fibroblastic to the osteogenic compartment. Despite the continuous presence of [3H]thymidine, less than 35% of both osteoblasts and osteocytes were labeled at 5 days, indicating that only one-third of the osteoprogenitor cells had cycled prior to differentiation. Spatial clustering of [3H]thymidine-labeled cells was measured by computer-assisted morphometry and application of the Poisson distribution to assess contagion. Cluster size and number of labeled cells per cluster did not vary between 1-3 days, but the number of clusters increased 20-fold between Day 1 and Day 3. Three-dimensional reconstruction from serial sections showed that clusters formed long, tubular arrays of osteogenic cells up to eight cells in length and located within 2-3 cell layers from the bone surface. Selective killing of S-phase cells with two pulse labels of high specific activity [3H]thymidine at 1 and 2 days of culture completely blocked bone formation

Induction of L-form-like cell shape change of Bacillus subtilis under microculture conditions.

Science.gov (United States)

Shingaki, Ryuji; Kasahara, Yasuhiro; Iwano, Megumi; Kuwano, Masayoshi; Takatsuka, Tomomasa; Inoue, Tetsuyoshi; Kokeguchi, Susumu; Fukui, Kazuhiro

2003-09-01

A remarkable cell shape change was observed in Bacillus subtilis strain 168 under microculture conditions on CI agar medium (Spizizen's minimal medium supplemented with a trace amount of yeast extract and Casamino acids). Cells cultured under a cover glass changed in form from rod-shaped to spherical, large and irregular shapes that closely resembled L-form cells. The cell shape change was observed only with CI medium, not with Spizizen's minimum medium alone or other rich media. The whole-cell protein profile of cells grown under cover glass and cells grown on CI agar plates differed in several respects. Tandem mass analysis of nine gel bands which differed in protein expression between the two conditions showed that proteins related to nitrate respiration and fermentation were expressed in the shape-changed cells grown under cover glass. The cell shape change of CI cultures was repressed when excess KNO3 was added to the medium. Whole-cell protein analysis of the normal rod-shaped cells grown with 0.1% KNO3 and the shape-changed cells grown without KNO3 revealed that the expression of the branched-chain alpha-keto acid dehydrogenase complex (coded by the bfmB gene locus) was elevated in the shape-changed cells. Inactivation of the bfmB locus resulted in the repression of cell shape change, and cells in which bfmB expression was induced by IPTG did show changes in shape. Transmission electron microscopy of ultrathin sections demonstrated that the shape-changed cells had thin walls, and plasmolysis of cells fixed with a solution including 0.1 M sucrose was observed. Clarifying the mechanism of thinning of the cell wall may lead to the development of a new type of cell wall biosynthetic inhibitor.

Human endothelial colony-forming cells expanded with an improved protocol are a useful endothelial cell source for scaffold-based tissue engineering.

Science.gov (United States)

Denecke, Bernd; Horsch, Liska D; Radtke, Stefan; Fischer, Johannes C; Horn, Peter A; Giebel, Bernd

2015-11-01

One of the major challenges in tissue engineering is to supply larger three-dimensional (3D) bioengineered tissue transplants with sufficient amounts of nutrients and oxygen and to allow metabolite removal. Consequently, artificial vascularization strategies of such transplants are desired. One strategy focuses on endothelial cells capable of initiating new vessel formation, which are settled on scaffolds commonly used in tissue engineering. A bottleneck in this strategy is to obtain sufficient amounts of endothelial cells, as they can be harvested only in small quantities directly from human tissues. Thus, protocols are required to expand appropriate cells in sufficient amounts without interfering with their capability to settle on scaffold materials and to initiate vessel formation. Here, we analysed whether umbilical cord blood (CB)-derived endothelial colony-forming cells (ECFCs) fulfil these requirements. In a first set of experiments, we showed that marginally expanded ECFCs settle and survive on different scaffold biomaterials. Next, we improved ECFC culture conditions and developed a protocol for ECFC expansion compatible with 'Good Manufacturing Practice' (GMP) standards. We replaced animal sera with human platelet lysates and used a novel type of tissue-culture ware. ECFCs cultured under the new conditions revealed significantly lower apoptosis and increased proliferation rates. Simultaneously, their viability was increased. Since extensively expanded ECFCs could still settle on scaffold biomaterials and were able to form tubular structures in Matrigel assays, we conclude that these ex vivo-expanded ECFCs are a novel, very potent cell source for scaffold-based tissue engineering. Copyright © 2013 John Wiley & Sons, Ltd.

Morphology and steroidogenesis of cultured granulosa cells obtained from ovaries of women treated with ionizing radiation

International Nuclear Information System (INIS)

Skrzypczak, J.

1997-01-01

The object of the study was the morphology and steroidogenesis of cultured granulosa cells obtained from 6 women aged 28-39 years who, because of Ib cervix carcinoma, were treated with ionizing radiation and later underwent surgery. It was observed that the granulosa cells were viable, had strong proliferative ability, and formed a monolayer on day 2 of culture. Contrary to our expectations, these cells produced larger amounts of steroids in culture than the control cells harvested from normal ovaries in late follicular phase. It was also found that the cells treated with ionizing radiation responded to exogenous gonadotropins with higher production of progesterone and estradiol than the controls. It is concluded that the increase in metabolic activity by granulosa cells from ovaries which had been indirectly affected by ionizing radiation is manifested by the stimulating influence of radiation on steroidogenesis. (author)

Mutation in cultured mammalian cells

International Nuclear Information System (INIS)

Nakamura, N.; Okada, S.

1982-01-01

Mammalian cell cultures were exposed to gamma-rays at various dose rates. Dose-rate effects were observed in cultured somatic cells of the mouse for cell killing and mutations resistant to 6-thioguanine (TGsup(r)) and to methotrexate (MTXsup(r)). Linear quadratic model may be applied to cell killing and TGsup(r) mutations in some cases but can not explain the whole data. Results at low doses with far low dose-rate were not predictable from data at high doses with acute or chronic irradiation. Radioprotective effects of dimethyl sulfoxide were seen only after acute exposure but not after chronic one, suggesting that damages by indirect action of radiations may be potentially reparable by cells. TGsup(r) mutations seem to contain gross structural changes whereas MTXsup(r) ones may have smaller alterations. (Namekawa, K.)

Cell-free DNA in a three-dimensional spheroid cell culture model

DEFF Research Database (Denmark)

Aucamp, Janine; Calitz, Carlemi; Bronkhorst, Abel J.

2017-01-01

Background Investigating the biological functions of cell-free DNA (cfDNA) is limited by the interference of vast numbers of putative sources and causes of DNA release into circulation. Utilization of three-dimensional (3D) spheroid cell cultures, models with characteristics closer to the in vivo...... cultures can serve as effective, simplified in vivo-simulating “closed-circuit” models since putative sources of cfDNA are limited to only the targeted cells. In addition, cfDNA can also serve as an alternative or auxiliary marker for tracking spheroid growth, development and culture stability. Biological...... significance 3D cell cultures can be used to translate “closed-circuit” in vitro model research into data that is relevant for in vivo studies and clinical applications. In turn, the utilization of cfDNA during 3D culture research can optimize sample collection without affecting the stability of the growth...

Cell culture techniques in honey bee research

Science.gov (United States)

Cell culture techniques are indispensable in most if not all life science disciplines to date. Wherever cell culture models are lacking scientific development is hampered. Unfortunately this has been and still is the case in honey bee research because permanent honey bee cell lines have not yet been...

A multifunctional 3D co-culture system for studies of mammary tissue morphogenesis and stem cell biology.

Directory of Open Access Journals (Sweden)

Jonathan J Campbell

Full Text Available Studies on the stem cell niche and the efficacy of cancer therapeutics require complex multicellular structures and interactions between different cell types and extracellular matrix (ECM in three dimensional (3D space. We have engineered a 3D in vitro model of mammary gland that encompasses a defined, porous collagen/hyaluronic acid (HA scaffold forming a physiologically relevant foundation for epithelial and adipocyte co-culture. Polarized ductal and acinar structures form within this scaffold recapitulating normal tissue morphology in the absence of reconstituted basement membrane (rBM hydrogel. Furthermore, organoid developmental outcome can be controlled by the ratio of collagen to HA, with a higher HA concentration favouring acinar morphological development. Importantly, this culture system recapitulates the stem cell niche as primary mammary stem cells form complex organoids, emphasising the utility of this approach for developmental and tumorigenic studies using genetically altered animals or human biopsy material, and for screening cancer therapeutics for personalised medicine.

MEMS-based dynamic cell-to-cell culture platforms using electrochemical surface modifications

International Nuclear Information System (INIS)

Chang, Jiyoung; Lin, Liwei; Yoon, Sang-Hee; Mofrad, Mohammad R K

2011-01-01

MEMS-based biological platforms with the capability of both spatial placements and time releases of living cells for cell-to-cell culture experiments have been designed and demonstrated utilizing electrochemical surface modification effects. The spatial placement is accomplished by electrochemical surface modification of substrate surfaces to be either adhesive or non-adhesive for living cells. The time control is achieved by the electrical activation of the selective indium tin oxide co-culture electrode to allow the migration of living cells onto the electrode to start the cell-to-cell culture studies. Prototype devices have a three-electrode design with an electrode size of 50 × 50 µm 2 and the separation gaps of 2 µm between them. An electrical voltage of −1.5 V has been used to activate the electrodes independently and sequentially to demonstrate the dynamic cell-to-cell culture experiments of NIH 3T3 fibroblast and Madin Darby canine kidney cells. As such, this MEMS platform could be a basic yet versatile tool to characterize transient cell-to-cell interactions

Slow conduction in mixed cultured strands of primary ventricular cells and stem cell-derived cardiomyocytes

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Jan Pavel Kucera

2015-09-01

Full Text Available Modern concepts for the treatment of myocardial diseases focus on novel cell therapeutic strategies involving stem cell-derived cardiomyocytes (SCMs. However, functional integration of SCMs requires similar electrophysiological properties as primary cardiomyocytes (PCMs and the ability to establish intercellular connections with host myocytes in order to contribute to the electrical and mechanical activity of the heart. The aim of this project was to investigate the properties of cardiac conduction in a co-culture approach using SCMs and PCMs in cultured cell strands. Murine embryonic SCMs were pooled with fetal ventricular cells and seeded in predefined proportions on microelectrode arrays to form patterned strands of mixed cells. Conduction velocity (CV was measured during steady state pacing. SCM excitability was estimated from action potentials measured in single cells using the patch clamp technique. Experiments were complemented with computer simulations of conduction using a detailed model of cellular architecture in mixed cell strands.CV was significantly lower in strands composed purely of SCMs (5.5±1.5 cm/s, n=11 as compared to PCMs (34.9±2.9 cm/s, n=21 at similar refractoriness (100% SCMs: 122±25 ms, n=9; 100% PCMs: 139±67 ms, n=14. In mixed strands combining both cell types, CV was higher than in pure SCMs strands, but always lower than in 100% PCM strands. Computer simulations demonstrated that both intercellular coupling and electrical excitability limit CV.These data provide evidence that in cultures of murine ventricular cardiomyocytes, SCMs cannot restore CV to control levels resulting in slow conduction, which may lead to reentry circuits and arrhythmias.

Democratic cultural policy : democratic forms and policy consequences

OpenAIRE

Gray, Clive

2012-01-01

The forms that are adopted to give practical meaning to democracy are assessed to identify what their implications are for the production of public policies in general and cultural policies in particular. A comparison of direct, representative, democratic elitist and deliberative versions of democracy identifies clear differences between them in terms of policy form and democratic practice. Further elaboration of these differences and their consequences are identified as areas for further res...

Microfluidic engineered high cell density three-dimensional neural cultures

Science.gov (United States)

Cullen, D. Kacy; Vukasinovic, Jelena; Glezer, Ari; La Placa, Michelle C.

2007-06-01

Three-dimensional (3D) neural cultures with cells distributed throughout a thick, bioactive protein scaffold may better represent neurobiological phenomena than planar correlates lacking matrix support. Neural cells in vivo interact within a complex, multicellular environment with tightly coupled 3D cell-cell/cell-matrix interactions; however, thick 3D neural cultures at cell densities approaching that of brain rapidly decay, presumably due to diffusion limited interstitial mass transport. To address this issue, we have developed a novel perfusion platform that utilizes forced intercellular convection to enhance mass transport. First, we demonstrated that in thick (>500 µm) 3D neural cultures supported by passive diffusion, cell densities =104 cells mm-3), continuous medium perfusion at 2.0-11.0 µL min-1 improved viability compared to non-perfused cultures (p death and matrix degradation. In perfused cultures, survival was dependent on proximity to the perfusion source at 2.00-6.25 µL min-1 (p 90% viability in both neuronal cultures and neuronal-astrocytic co-cultures. This work demonstrates the utility of forced interstitial convection in improving the survival of high cell density 3D engineered neural constructs and may aid in the development of novel tissue-engineered systems reconstituting 3D cell-cell/cell-matrix interactions.

Heparin concentration is critical for cell culture with human platelet lysate.

Science.gov (United States)

Hemeda, Hatim; Kalz, Jana; Walenda, Gudrun; Lohmann, Michael; Wagner, Wolfgang

2013-09-01

Culture media for mesenchymal stromal cells (MSCs) are generally supplemented with fetal bovine serum. Human platelet lysate (hPL) has been proven to be a very effective alternative without the risk of xenogeneic infections or immune reactions. In contrast to fetal bovine serum, hPL comprises plasma, and anticoagulants-usually unfractionated heparin (UFH)-need to be added to prevent gel formation. Cultures of MSCs in hPL media with various concentrations of UFH and enoxaparin, a low-molecular-weight heparin (LMWH), were systematically compared with regard to proliferation, fibroblastoid colony-forming unit frequency, immunophenotype and in vitro differentiation. At least 0.61 IU/mL UFH or 0.024 mg/mL LMWH was necessary for reliable prevention of coagulation of hPL pools used in this study. Higher concentrations impaired cellular proliferation in a dose-dependent manner even without benzyl alcohol, which is commonly added to heparins as a bacteriostatic agent. Colony-forming unit frequency was also reduced at higher heparin concentrations, particularly with LMWH, whereas no significant effect was observed on cellular morphology or immunophenotype. High concentrations of heparins reduced the in vitro differentiation toward adipogenic and osteogenic lineages. Heparin concentration is critical for culture of MSCs in hPL media; this is of particular relevance for cellular therapy where cell culture procedures need to be optimized and standardized. Copyright © 2013 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

The Human Glioblastoma Cell Culture Resource: Validated Cell Models Representing All Molecular Subtypes

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Yuan Xie

2015-10-01

Full Text Available Glioblastoma (GBM is the most frequent and malignant form of primary brain tumor. GBM is essentially incurable and its resistance to therapy is attributed to a subpopulation of cells called glioma stem cells (GSCs. To meet the present shortage of relevant GBM cell (GC lines we developed a library of annotated and validated cell lines derived from surgical samples of GBM patients, maintained under conditions to preserve GSC characteristics. This collection, which we call the Human Glioblastoma Cell Culture (HGCC resource, consists of a biobank of 48 GC lines and an associated database containing high-resolution molecular data. We demonstrate that the HGCC lines are tumorigenic, harbor genomic lesions characteristic of GBMs, and represent all four transcriptional subtypes. The HGCC panel provides an open resource for in vitro and in vivo modeling of a large part of GBM diversity useful to both basic and translational GBM research.

Cell sources for in vitro human liver cell culture models

Science.gov (United States)

Freyer, Nora; Damm, Georg; Seehofer, Daniel; Knöspel, Fanny

2016-01-01

In vitro liver cell culture models are gaining increasing importance in pharmacological and toxicological research. The source of cells used is critical for the relevance and the predictive value of such models. Primary human hepatocytes (PHH) are currently considered to be the gold standard for hepatic in vitro culture models, since they directly reflect the specific metabolism and functionality of the human liver; however, the scarcity and difficult logistics of PHH have driven researchers to explore alternative cell sources, including liver cell lines and pluripotent stem cells. Liver cell lines generated from hepatomas or by genetic manipulation are widely used due to their good availability, but they are generally altered in certain metabolic functions. For the past few years, adult and pluripotent stem cells have been attracting increasing attention, due their ability to proliferate and to differentiate into hepatocyte-like cells in vitro. However, controlling the differentiation of these cells is still a challenge. This review gives an overview of the major human cell sources under investigation for in vitro liver cell culture models, including primary human liver cells, liver cell lines, and stem cells. The promises and challenges of different cell types are discussed with a focus on the complex 2D and 3D culture approaches under investigation for improving liver cell functionality in vitro. Finally, the specific application options of individual cell sources in pharmacological research or disease modeling are described. PMID:27385595

Growth of melanocytes in human epidermal cell cultures

International Nuclear Information System (INIS)

Staiano-Coico, L.; Hefton, J.M.; Amadeo, C.; Pagan-Charry, I.; Madden, M.R.; Cardon-Cardo, C.

1990-01-01

Epidermal cell cultures were grown in keratinocyte-conditioned medium for use as burn wound grafts; the melanocyte composition of the grafts was studied under a variety of conditions. Melanocytes were identified by immunohistochemistry based on a monoclonal antibody (MEL-5) that has previously been shown to react specifically with melanocytes. During the first 7 days of growth in primary culture, the total number of melanocytes in the epidermal cultures decreased to 10% of the number present in normal skin. Beginning on day 2 of culture, bipolar melanocytes were present at a mean cell density of 116 +/- 2/mm2; the keratinocyte to melanocyte ratio was preserved during further primary culture and through three subpassages. Moreover, exposure of cultures to mild UVB irradiation stimulated the melanocytes to proliferate, suggesting that the melanocytes growing in culture maintained their responsiveness to external stimuli. When the sheets of cultured cells were enzymatically detached from the plastic culture flasks before grafting, melanocytes remained in the basal layer of cells as part of the graft applied to the patient

Cell Culture as an Alternative in Education.

Science.gov (United States)

Nardone, Roland M.

1990-01-01

Programs that are intended to inform and provide "hands-on" experience for students and to facilitate the introduction of cell culture-based laboratory exercises into the high school and college laboratory are examined. The components of the CellServ Program and the Cell Culture Toxicology Training Programs are described. (KR)

Comparison of various methods of detection of different forms of dengue virus type 2 RNA in cultured cells

International Nuclear Information System (INIS)

Liu, H.S.; Lin, Y.L.; Chen, C.C.

1997-01-01

In this report, the sensitivity of various methods of detection of dengue virus type 2 (DEN-2) sense, antisense, replicative intermediate (RI) and replicative form (RF) RNAs in infected mosquito Aedes pseudoscutellaris AP-61 and mammalian baby hamster kidney BHK-21 cells is compared. LiCl precipitation was used for separation of viral RF RNA from RI RNA. Our results show that reverse transcription-polymerase chain reaction (RT-PCR) followed by Southern blot analysis and slot blot hybridisation of LiCl-fractionated RNA were the most sensitive methods of detection of viral RNA and determination of its single-stranded form. Northern blot analysis was the least sensitive method of detection of any form of viral RNA. U sing slot blot hybridisation of LiCl-precipitated RNA, viral RI RNA containing de novo synthesised negative strand viral RNA was first detected 30 min after virus inoculation in both cell lines. This is the earliest time of detection of DEN viral RNA synthesis in host cells so far reported. However, RF RNA could not be detected until 24 hrs post infection (p.i.) in AP-61 and 2 days p.i. in BHK-21 cells, respectively. The sequential order of individual forms of viral RNA detected in the infected cells was RI, RF and genomic RNAs. Viral RNA was detected in AP-61 cells always earlier than in BHK-21 cells. Moreover, the level of viral RNA in AP-61 cells was higher than that in BHK-21 cells, suggesting that the virus replicated more actively in AP-61 cells. In conclusion, the LiCl separation of viral RNA followed by slot blot hybridisation was found to be the most sensitive and reliable method of detection of DEN virus RI, RF and genomic RNAs in the infected cells. Moreover, this method can be applied to determine the replication status of any single-stranded RNA virus in the host. (authors)

Quantum dot labeling and tracking of cultured limbal epithelial cell transplants in-vitro

Science.gov (United States)

Genicio, Nuria; Paramo, Juan Gallo; Shortt, Alex J.

2015-01-01

PURPOSE Cultured human limbal epithelial cells (HLEC) have shown promise in the treatment of limbal stem cell deficiency but little is known about their survival, behaviour and long-term fate post transplantation. The aim of this research was to evaluate, in-vitro, quantum dot (QDot) technology as a tool for tracking transplanted HLEC. METHODS In-vitro cultured HLEC were labeled with Qdot nanocrystals. Toxicity was assessed using live-dead assays. The effect on HLEC function was assessed using colony forming efficiency assays and expression of CK3, P63alpha and ABCG2. Sheets of cultured HLEC labeled with Qdot nanocrystals were transplanted onto decellularised human corneo-scleral rims in an organ culture model and observed to investigate the behaviour of transplanted cells. RESULTS Qdot labeling had no detrimental effect on HLEC viability or function in-vitro. Proliferation resulted in a gradual reduction in Qdot signal but sufficient signal was present to allow tracking of cells through multiple generations. Cells labeled with Qdots could be reliably detected and observed using confocal microscopy for at least 2 weeks post transplantation in our organ culture model. In addition it was possible to label and observe epithelial cells in intact human corneas using the Rostock corneal module adapted for use with the Heidelberg HRA. CONCLUSIONS This work demonstrates that Qdots combined with existing clinical equipment could be used to track HLEC for up to 2 weeks post transplantation, however, our model does not permit the assessment of cell labeling beyond 2 weeks. Further characterisation in in-vivo models are required. PMID:26024089

The usefulness of three-dimensional cell culture in induction of cancer stem cells from esophageal squamous cell carcinoma cell lines

International Nuclear Information System (INIS)

Fujiwara, Daisuke; Kato, Kazunori; Nohara, Shigeo; Iwanuma, Yoshimi; Kajiyama, Yoshiaki

2013-01-01

Highlights: •Spheroids were created from esophageal carcinoma cells using NanoCulture® Plates. •The proportion of strongly ALDH-positive cells increased in 3-D culture. •Expression of cancer stem cell-related genes was enhanced in 3-D culture. •CA-9 expression was enhanced, suggesting hypoxia had been induced in 3-D culture. •Drug resistance was increased. 3-D culture is useful for inducing cancer stem cells. -- Abstract: In recent years, research on resistance to chemotherapy and radiotherapy in cancer treatment has come under the spotlight, and researchers have also begun investigating the relationship between resistance and cancer stem cells. Cancer stem cells are assumed to be present in esophageal cancer, but experimental methods for identification and culture of these cells have not yet been established. To solve this problem, we created spheroids using a NanoCulture® Plate (NCP) for 3-dimensional (3-D) cell culture, which was designed as a means for experimentally reproducing the 3-D structures found in the body. We investigated the potential for induction of cancer stem cells from esophageal cancer cells. Using flow cytometry we analyzed the expression of surface antigen markers CD44, CD133, CD338 (ABCG2), CD318 (CDCP1), and CD326 (EpCAM), which are known cancer stem cell markers. None of these surface antigen markers showed enhanced expression in 3-D cultured cells. We then analyzed aldehyde dehydrogenase (ALDH) enzymatic activity using the ALDEFLUOR reagent, which can identify immature cells such as stem cells and precursor cells. 3-D-cultured cells were strongly positive for ALDH enzyme activity. We also analyzed the expression of the stem cell-related genes Sox-2, Nanog, Oct3/4, and Lin28 using RT-PCR. Expression of Sox-2, Nanog, and Lin28 was enhanced. Analysis of expression of the hypoxic surface antigen marker carbonic anhydrase-9 (CA-9), which is an indicator of cancer stem cell induction and maintenance, revealed that CA-9 expression

Isolated rat dental pulp cell culture and transplantation with an alginate scaffold.

Science.gov (United States)

Fujiwara, Shiro; Kumabe, Shunji; Iwai, Yasutomo

2006-05-01

Many studies have been conducted on tissue stem cells in the field of regenerative medicine, and cultured dental pulp mesenchymal cells have been reported to secrete dentin matrix. In the present study we used alginate as a scaffold to transplant subcultured rat dental-pulp-derived cells subcutaneously into the back of nude mice. We found that when beta-glycerophosphate was added to the culture medium, the mRNA of the dentin sialophosphoprotein (DSPP) gene coding dentin sialoprotein (DSP) and dentin phosphoprotein (DPP) was expressed, and an increase in alkaline phosphatase, an early marker of odontoblast differentiation, was also demonstrated. Six weeks after implantation, subcutaneous formation of radiopaque calcified bodies was observed in situ. Immunohistochemical and fine structure studies identified expression of type I collagen, type III collagen, and DSP in the mineralizing transplants, and isolated odontoblast-like cells began to form dentin-like hard tissue formation. Scattered autolyzing apoptotic cells were also observed in the transplants. The study showed that subcultured rat dental-pulp-derived cells actively differentiate into odontoblast-like cells and induce calcification in an alginate scaffold.

PECULIARITIES OF SECONDARY METABOLITES BIOSYNTHESIS IN PLANT CELL CULTURES

Directory of Open Access Journals (Sweden)

A.M. NOSOV

2014-06-01

Full Text Available metabolites formation in plant cell cultures of Panax spp., (ginsenosides; Dioscorea deltoidea (steroid glycosides; Ajuga reptans, Serratula coronata, Rhaponticum carthamoides (ecdisteroids; Polyscias spp., (triterpene glycosides, Taxus spp. (taxoids, Stevia rebaudiana (diterpene steviol-glycosides, Stephania glabra (alkaloids. They are some regular trends of secondary metabolites synthesis in the plant cell culture:It can be noted the stable synthesis of the compound promoting cell proliferation. Indeed, cell cultures of Dioscorea deltoidea were demonstrated to accumulate only furostanol glycosides, which promoted cell division. Furostanol glycoside content of Dioscorea strain DM-0.5 was up to 6 - 12% by dry biomass.Panax ginseng and P. japonicus plant cell cultures synthesize as minimum seven triterpene glycosides (ginsenosides, the productivity of these compounds was up to 6.0 - 8.0% on dry biomass.By contrast, the detectable synthesis of diterpene steviol-glycosides in cultivated cells of Stevia rebaudiana initiated in the mixotrophic cultures during chloroplast formation only.Despite these differences, or mainly due to them, plant cell cultures have become an attractive source of phytochemicals in alternative to collecting wild plants. It provides a guideline to bioreactor-based production of isoprenoids using undifferentiated plant cell cultures. 

Substrate utilisation by plant-cell cultures

Energy Technology Data Exchange (ETDEWEB)

Fowler, M W

1982-01-01

Plant cell cultures have been grown on a wide range of carbon sources in addition to the traditional ones of sucrose and glucose. Biomass yields and growth rates vary greatly between the different carbon sources and there is a variation in response between different cell cultures to individual carbon sources. Some attempts have been made to grow cell cultures on 'waste' and related carbon sources, such as lactose, maltose, starch, molasses and milk whey. Only maltose was found to support growth to anything near the levels observed with glucose and sucrose. In the case of molasses carbon source cell growth was either non-existent or only just measurable. All the data point to glucose as being the most suitable carbon source, principally on the grounds of biomass yield and growth rate. It should be noted, however, that other carbon sources do appear to have a major (positive) influence on natural product synthesis. Uptake into the cell is an important aspect of carbohydrate utilisation. There is strong evidence that from disaccharides upwards, major degradation to smaller units occurs before uptake. In some cases the necessary enzymes appear to be excreted into the culture broth, in others they may be located within the cell wall; invertase that hydrolyses sucrose is a good example. Once the products of carbohydrate degradation and mobilisation enter the cell they may suffer one of two fates, oxidation or utilisation for biosynthesis. The precise split between these two varies depending on such factors as cell growth rate, cell size, nutrient broth composition and carbohydrate status of the cells. In general rapidly growing cells have a high rate of oxidation, whereas cells growing more slowly tend to be more directed towards biosynthesis. Carbohydrate utilisation is a key area of study, underpinning as it does both biomass yield and natural product synthesis. (Refs. 13).

Biona-C Cell Culture pH Monitoring System

Science.gov (United States)

Friedericks, C.

1999-01-01

Sensors 2000! is developing a system to demonstrate the ability to perform accurate, real-time measurements of pH and CO2 in a cell culture media in Space. The BIONA-C Cell Culture pH Monitoring System consists of S2K! developed ion selective sensors and control electronics integrated with the fluidics of a cell culture system. The integrated system comprises a "rail" in the Cell Culture Module (CCM) of WRAIR (Space Biosciences of Walter Read Army Institute of Research). The CCM is a Space Shuttle mid-deck locker experiment payload. The BIONA-C is displayed along with associated graphics and text explanations. The presentation will stimulate interest in development of sensor technology for real-time cell culture measurements. The transfer of this technology to other applications will also be of interest. Additional information is contained in the original document.

Three-dimensional co-culture facilitates the differentiation of embryonic stem cells into mature cardiomyocytes.

Science.gov (United States)

Ou, Dong-Bo; He, Yong; Chen, Rui; Teng, Ji-Wei; Wang, Hong-Tao; Zeng, Di; Liu, Xiong-Tao; Ding, Lu; Huang, Jin-Yan; Zheng, Qiang-Sun

2011-12-01

The cardiomyocyte (CM) differentiation of embryonic stem cells (ESCs) is routinely cultured as two-dimensional (2D) monolayer, which doesn't mimic in vivo physiological environment and may lead to low differentiated level of ESCs. Here, we develop a novel strategy that enhances CM differentiation of ESCs in collagen matrix three-dimensional (3D) culture combined with indirect cardiac fibroblasts co-culture. ESCs were cultured in hanging drops to form embryoid bodies (EBs) and then applied on collagen matrix. The EBs were indirectly co-cultured with cardiac fibroblasts by the hanging cell culture inserts (PET 1 µm). The molecular expressions and ultrastructural characteristics of ESC-derived CMs (ESCMs) were analyzed by real time RT-PCR, immunocytochemistry, and Transmission Electron Microscopy (TEM). We found that the percentage of beating EBs with cardiac fibroblasts co-culture was significantly higher than that without co-culture after differentiation period of 8 days. Type I collagen used as 3D substrates enhanced the late-stage CM differentiation of ESCs and had effect on ultrastructural mature of ESCMs in late-stage development. The combined effects of 3D and co-culture that mimic in vivo physiological environment further improved the efficiency of CM differentiation from ESCs, resulting in fiber-like structures of cardiac cells with organized sarcomeric structure in ESCMs. This novel 3D co-culture system emphasizes the fact that the ESC differentiation is actively responding to cues from their environment and those cues can drive phenotypic control, which provides a useful in vitro model to investigate CM differentiation of stem cells. Copyright © 2011 Wiley Periodicals, Inc.

Culture of equine bone marrow mononuclear fraction and adipose tissue-derived stromal vascular fraction cells in different media

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Gesiane Ribeiro

2013-12-01

Full Text Available The objective of this study was to evaluate the culture of equine bone marrow mononuclear fraction and adipose tissue - derived stromal vascular fraction cells in two different cell culture media. Five adult horses were submitted to bone marrow aspiration from the sternum, and then from the adipose tissue of the gluteal region near the base of the tail. Mononuclear fraction and stromal vascular fraction were isolated from the samples and cultivated in DMEM medium supplemented with 10% fetal bovine serum or in AIM-V medium. The cultures were observed once a week with an inverted microscope, to perform a qualitative analysis of the morphology of the cells as well as the general appearance of the cell culture. Colony-forming units (CFU were counted on days 5, 15 and 25 of cell culture. During the first week of culture, differences were observed between the samples from the same source maintained in different culture media. The number of colonies was significantly higher in samples of bone marrow in relation to samples of adipose tissue.

[Research progress of Lgr5-positive stem cells in the formation of organoid in 3D culture].

Science.gov (United States)

He, Q Q; Li, A; Wang, M H; Gao, X

2018-06-07

Stem cell is critical to regeneration of tissue or organ of human. How to promote repair or regeneration in the tissues/organ using its pluripotency is always an important issue. Lgr5-possitive cell is one type of the stem cell-like cells capable of pluripotent differentiation in various tissues/organs of both humans and mice. Current study showed that single or small amount Lgr5-possitive stem cells can grow and form a plurality of organs in 3D culture system, and some organs can present similar biological and physiological properties with the progenitor they were derived. These studies provided new insight into future orientation, for example, Lgr5-possitive inner ear cells were confirmed as inner ear pluripotent cells population, the experiences obtained from organoid studies of Lgr5-possitive cells have certainly showed potential in the future study of inner ear stem cells. This review will focus on the recent progress associated with Lgr 5-positive stem cells forming organoids in the 3D culture.

Bioactive form of resveratrol in glioblastoma cells and its safety for normal brain cells

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Xiao-Hong Shu

2013-05-01

Full Text Available ABSTRACTBackground: Resveratrol, a plant polyphenol existing in grapes and many other natural foods, possesses a wide range of biological activities including cancer prevention. It has been recognized that resveratrol is intracellularly biotransformed to different metabolites, but no direct evidence has been available to ascertain its bioactive form because of the difficulty to maintain resveratrol unmetabolized in vivo or in vitro. It would be therefore worthwhile to elucidate the potential therapeutic implications of resveratrol metabolism using a reliable resveratrol-sensitive cancer cells.Objective: To identify the real biological form of trans-resveratrol and to evaluate the safety of the effective anticancer dose of resveratrol for the normal brain cells.Methods: The samples were prepared from the condition media and cell lysates of human glioblastoma U251 cells, and were purified by solid phase extraction (SPE. The samples were subjected to high performance liquid chromatography (HPLC and liquid chromatography/tandem mass spectrometry (LC/MS analysis. According to the metabolite(s, trans-resveratrol was biotransformed in vitro by the method described elsewhere, and the resulting solution was used to treat U251 cells. Meanwhile, the responses of U251 and primarily cultured rat normal brain cells (glial cells and neurons to 100μM trans-resveratrol were evaluated by multiple experimental methods.Results: The results revealed that resveratrol monosulfate was the major metabolite in U251 cells. About half fraction of resveratrol monosulfate was prepared in vitro and this trans-resveratrol and resveratrol monosulfate mixture showed little inhibitory effect on U251 cells. It is also found that rat primary brain cells (PBCs not only resist 100μM but also tolerate as high as 200μM resveratrol treatment.Conclusions: Our study thus demonstrated that trans-resveratrol was the bioactive form in glioblastoma cells and, therefore, the biotransforming

Protein biosynthesis in cultured human hair follicle cells.

Science.gov (United States)

Weterings, P J; Vermorken, A J; Bloemendal, H

1980-10-31

A new technique has been used for culturing human keratinocytes. The cells grow on the basement membrane-like capsules of bovine lenses. Lens cells were removed from the capsules by rigid trypsinization. In order to exclude any contamination with remaining living cells the isolated capsules were irradiated with X-rays at a dose of 10,000 rad. In this way human epithelial cells can be brought in culture from individual hair follicles. Since feeder cells are not used in this culture technique, the biosynthesis of keratinocyte proteins can be studied in these cultures. The newly synthesized proteins can be separated into a water-soluble, a urea-soluble, and a urea-insoluble fraction. Product analysis has been performed on the first two fractions revealing protein patterns identical to those of intact hair follicles. Product analysis of the urea-soluble fractions of microdissected hair follicles shows that the protein pattern of the cultured keratinocytes resembles the protein pattern of the hair follicle sheath. Studies on the metabolism of benzo(a)pyrene revealed that the enzyme aryl hydrocarbon hydroxylase (AHH) is present in cultured hair follicle cells. A possible use of our culture system for eventual detection of inherited predisposition for smoking-dependent lung cancer is discussed.

Induced recovery from near- and far-UV damage in cultured marsupial cells

International Nuclear Information System (INIS)

Hoy, D.A.

1982-01-01

Colony-forming ability of cultured rat kangaroo cells (Ptk-2) decreases with increasing exposure to light from a daylight fluorescent lamp. After reaching a minimum, survival increases with further exposure, forming a V-shaped survival curve. This increase is inhibited by low concentrations of the protein synthesis inhibitor cycloheximide. The resulting V-shaped survival curve was characterized with respect to several experimental parameters; it appears to be due to an induced repair system dependent on protein synthesis. These results suggest that induced repair, dependent on protein synthesis, in response to fluorescent, near UV, and far UV light damage, is a major repair pathway in Ptk-2 cells, and provides a characterizable system that can elucidate induced repair mechanisms in other mammalian cells

VISUAL CULTURE AS A MEANS OF FORMING A COMMON AND PROFESSIONAL CULTURE OF A PERSON

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N. V. Syrova

2018-01-01

Full Text Available Introduction. The article is devoted to the analysis of the visual culture, which forms the general and professional culture of a person in many ways. Attention is paid to the culture of perception of visual images, the ability to analyze them, evaluate, compare, also the features of visual thinking and creative activity, directly relating to it, are considered. The mastering of visual culture is grounded by the specificity of various creative specialties and is a component of the educational process.Materials and Methods. The theory of personality formation and development is the methodological basis of the article. During the research, the analysis of the scientific and theoretical concept of "visual culture" in the system of general and professional human culture was used.Results. The article illustrates that the artistic vision, developed in the process of visual culture formation, starting from childhood, actively participates in the preparation of the ground for the origin of an artistic image, which is realized in the material later. With the development of the creative imagination of the learner, also the development of thinking and memory takes place inevitably, that is harmonization of all parts of the brain is carried out, and this process must be taken into account in the upbringing and education, the formation of the personality, and the formed visual culture is the basis for the improvement of all verges of the student's creative abilities.Discussion and Conclusions. The conclusion is made that visual culture being an integral part of the educational process is the necessary condition for entering the sociocultural space. The education of a high level of visual culture in a modern information and technically replete society is one of the necessary components of the formation of a general and professional culture of a person and it is desirable to begin this process with a student, and even better, from school-days.

An evaluation of the choice of feeder cell growth arrest for the production of cultured epidermis.

Science.gov (United States)

Chugh, Rishi Man; Chaturvedi, Madhusudan; Yerneni, Lakshmana Kumar

2015-12-01

Growth arrested 3T3 cells have been used as feeder cells in human epidermal keratinocyte cultures to produce cultured epidermal autografts for the treatment of burns. The feeder cells were ideally growth-arrested by gamma-irradiation. Alternatively, growth arrest by mitomycin C treatment is a cost effective option. We compared the functional efficacy of these two approaches in keratinocyte cultures by colony forming efficiency, the net growth area of colonies, BrdU labeling and histological features of cultured epidermal sheets. The growth area estimation involved a semi-automated digital technique using the Adobe Photoshop and comprised of isolation and enumeration of red pixels in Rhodamine B-stained keratinocyte colonies. A further refinement of the technique led to the identification of critical steps to increasing the degree of accuracy and enabling its application as an extension of colony formation assay. The results on feeder cell functionality revealed that the gamma irradiated feeders influenced significantly higher colony forming efficiency and larger growth area than the mitomycin C treated feeders. The BrdU labeling study indicated significant stimulation of the overall keratinocyte proliferation by the gamma irradiated feeders. The cultured epidermal sheets produced by gamma feeders were relatively thicker than those produced by mitomycin C feeders. We discussed the clinical utility of mitomycin C feeders from the viewpoint of cost-effective burn care in developing countries. Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.

21 CFR 864.2280 - Cultured animal and human cells.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cultured animal and human cells. 864.2280 Section... Cultured animal and human cells. (a) Identification. Cultured animal and human cells are in vitro cultivated cell lines from the tissue of humans or other animals which are used in various diagnostic...

Delineation of a novel pre-B cell component in plasma cell myeloma: immunochemical, immunophenotypic, genotypic, cytologic, cell culture, and kinetic features.

Science.gov (United States)

Grogan, T M; Durie, B G; Lomen, C; Spier, C; Wirt, D P; Nagle, R; Wilson, G S; Richter, L; Vela, E; Maxey, V

1987-10-01

A novel pre-B cell component in direct and cultured myeloma bone marrow material has been delineated by using immunochemistry and flow cytometry techniques. Our phenotypic studies suggest a novel hybrid expression of pre-B and plasma cell antigens with coexpression of cytoplasmic mu, common acute lymphoblastic leukemia antigen, terminal deoxynucleotidyl transferase, and plasma cell antigens (PCA-1 and PC-1). This suggests that myeloma pre-B-like cells are aberrant malignant cells and not normal pre-B lymphocytic counterparts. With the advantage of a pure and stable source of these cells from M3 culture to allow molecular characterization, we performed one- and two-dimensional gel electrophoresis and Western blotting. We found that the cytoplasmic mu in myeloma pre-B-like cells has a molecular weight of 74,000 daltons and an isoelectric point of 6.3 and that it is strikingly homogeneous and discrete in size and charge compared with standard secretory mu, which suggests an aberrant, mutant, or monoclonal form of mu. Monoclonality was further evidenced by heavy- and light-chain immunoglobulin gene rearrangements demonstrated with JH and C kappa probes. We also established that this novel myeloma pre-B component is a major proliferative element as determined by double-labeling experiments with phenotype coupled to labeling/proliferative indexes. Our stimulatory studies indicate some capacity of these cells to mature on exposure to phorbol esters. These myeloma pre-B cells may represent the stem cell or self-renewal component in myeloma. Our establishment of these cells in long-term culture offers a considerable asset in studying the immature cells, which may be critical to the immortalization of myeloma.

Culture of human mesenchymal stem cells using a candidate pharmaceutical grade xeno-free cell culture supplement derived from industrial human plasma pools.

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Díez, José M; Bauman, Ewa; Gajardo, Rodrigo; Jorquera, Juan I

2015-03-13

Fetal bovine serum (FBS) is an animal product used as a medium supplement. The animal origin of FBS is a concern if cultured stem cells are to be utilized for human cell therapy. Therefore, a substitute for FBS is desirable. In this study, an industrial, xeno-free, pharmaceutical-grade supplement for cell culture (SCC) under development at Grifols was tested for growth of human mesenchymal stem cells (hMSCs), cell characterization, and differentiation capacity. SCC is a freeze-dried product obtained through cold-ethanol fractionation of industrial human plasma pools from healthy donors. Bone marrow-derived hMSC cell lines were obtained from two commercial suppliers. Cell growth was evaluated by culturing hMSCs with commercial media or media supplemented with SCC or FBS. Cell viability and cell yield were assessed with an automated cell counter. Cell surface markers were studied by indirect immunofluorescence assay. Cells were cultured then differentiated into adipocytes, chondrocytes, osteoblasts, and neurons, as assessed by specific staining and microscopy observation. SCC supported the growth of commercial hMSCs. Starting from the same number of seeded cells in two consecutive passages of culture with medium supplemented with SCC, hMSC yield and cell population doubling time were equivalent to the values obtained with the commercial medium and was consistent among lots. The viability of hMSCs was higher than 90%, while maintaining the characteristic phenotype of undifferentiated hMSCs (positive for CD29, CD44, CD90, CD105, CD146, CD166 and Stro-1; negative for CD14 and CD19). Cultured hMSCs maintained the potential for differentiation into adipocytes, chondrocytes, osteoblasts, and neurons. The tested human plasma-derived SCC sustains the adequate growth of hMSCs, while preserving their differentiation capacity. SCC can be a potential candidate for cell culture supplement in advanced cell therapies.

Differential marker expression by cultures rich in mesenchymal stem cells

Science.gov (United States)

2013-01-01

Background Mesenchymal stem cells have properties that make them amenable to therapeutic use. However, the acceptance of mesenchymal stem cells in clinical practice requires standardized techniques for their specific isolation. To date, there are no conclusive marker (s) for the exclusive isolation of mesenchymal stem cells. Our aim was to identify markers differentially expressed between mesenchymal stem cell and non-stem cell mesenchymal cell cultures. We compared and contrasted the phenotype of tissue cultures in which mesenchymal stem cells are rich and rare. By initially assessing mesenchymal stem cell differentiation, we established that bone marrow and breast adipose cultures are rich in mesenchymal stem cells while, in our hands, foreskin fibroblast and olfactory tissue cultures contain rare mesenchymal stem cells. In particular, olfactory tissue cells represent non-stem cell mesenchymal cells. Subsequently, the phenotype of the tissue cultures were thoroughly assessed using immuno-fluorescence, flow-cytometry, proteomics, antibody arrays and qPCR. Results Our analysis revealed that all tissue cultures, regardless of differentiation potential, demonstrated remarkably similar phenotypes. Importantly, it was also observed that common mesenchymal stem cell markers, and fibroblast-associated markers, do not discriminate between mesenchymal stem cell and non-stem cell mesenchymal cell cultures. Examination and comparison of the phenotypes of mesenchymal stem cell and non-stem cell mesenchymal cell cultures revealed three differentially expressed markers – CD24, CD108 and CD40. Conclusion We indicate the importance of establishing differential marker expression between mesenchymal stem cells and non-stem cell mesenchymal cells in order to determine stem cell specific markers. PMID:24304471

Optimization of Femtosecond Laser Polymerized Structural Niches to Control Mesenchymal Stromal Cell Fate in Culture

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Manuela T. Raimondi

2014-06-01

Full Text Available We applied two-photon polymerization to fabricate 3D synthetic niches arranged in complex patterns to study the effect of mechano-topological parameters on morphology, renewal and differentiation of rat mesenchymal stromal cells. Niches were formed in a photoresist with low auto-fluorescence, which enabled the clear visualization of the fluorescence emission of the markers used for biological diagnostics within the internal niche structure. The niches were structurally stable in culture up to three weeks. At three weeks of expansion in the niches, cell density increased by almost 10-fold and was 67% greater than in monolayer culture. Evidence of lineage commitment was observed in monolayer culture surrounding the structural niches, and within cell aggregates, but not inside the niches. Thus, structural niches were able not only to direct stem cell homing and colony formation, but also to guide aggregate formation, providing increased surface-to-volume ratios and space for stem cells to adhere and renew, respectively.

Chromosomal instability and telomere shortening in long-term culture of hematopoietic stem cells: insights from a cell culture model of RPS14 haploinsufficiency.

Science.gov (United States)

Thomay, K; Schienke, A; Vajen, B; Modlich, U; Schambach, A; Hofmann, W; Schlegelberger, B; Göhring, G

2014-01-01

The fate of cultivated primary hematopoietic stem cells (HSCs) with respect to genetic instability and telomere attrition has not yet been described in great detail. Thus, knowledge of the genetic constitution of HSCs is important when interpreting results of HSCs in culture. While establishing a cell culture model for myelodysplastic syndrome with a deletion in 5q by performing RPS14 knockdown, we found surprising data that may be of importance for any CD34+ cell culture experiments. We performed cytogenetic analyses and telomere length measurement on transduced CD34+ cells and untransduced control cells to observe the effects of long-term culturing. Initially, CD34+ cells had a normal median telomere length of about 12 kb and showed no signs of chromosomal instability. During follow-up, the median telomere length seemed to decrease and, simultaneously, increased chromosomal instability could be observed - in modified and control cells. One culture showed a clonal monosomy 7 - independent of prior RPS14 knockdown. During further culturing, it seemed that the telomeres re-elongated, and chromosomes stabilized, while TERT expression was not elevated. In summary, irrespective of our results of RPS14 knockdown in the long-term culture of CD34+ cells, it becomes clear that cell culture artefacts inducing telomere shortening and chromosomal instability have to be taken into account and regular cytogenetic analyses should always be performed. © 2013 S. Karger AG, Basel.

The Important Role of FLT3-L in Ex Vivo Expansion of Hematopoietic Stem Cells following Co-Culture with Mesenchymal Stem Cells.

Science.gov (United States)

Oubari, Farhad; Amirizade, Naser; Mohammadpour, Hemn; Nakhlestani, Mozhdeh; Zarif, Mahin Nikougoftar

2015-01-01

Hematopoietic stem cells (HSCs) transplantation using umbilical cord blood (UCB) has improved during the last decade. Because of cell limitations, several studies focused on the ex vivo expansion of HSCs. Numerous investigations were performed to introduce the best cytokine cocktails for HSC expansion The majority used the Fms-related tyrosine kinase 3 ligand (FLT3-L) as a critical component. According to FLT3-L biology, in this study we have investigated the hypothesis that FLT3-L only effectively induces HSCs expansion in the presence of a mesenchymal stem cell (MSC) feeder. In this experimental study, HSCs and MSCs were isolated from UCB and placenta, respectively. HSCs were cultured in different culture conditions in the presence and absence of MSC feeder and cytokines. After ten days of culture, total nucleated cell count (TNC), cluster of differentiation 34+(CD34(+)) cell count, colony forming unit assay (CFU), long-term culture initiating cell (LTC-IC), homeobox protein B4 (HoxB4) mRNA and surface CD49d expression were evaluated. The fold increase for some culture conditions was compared by the t test. HSCs expanded in the presence of cytokines and MSCs feeder. The rate of expansion in the co-culture condition was two-fold more than culture with cytokines (Pculture condition at a level of 20-fold equal to the presence of stem cell factor (SCF), thrombopoietin (TPO) and FLT3-L without feeder cells. The number of extracted colonies from LTC-IC and CD49d expression compared with a cytokine cocktail condition meaningfully increased (Pculture with MSCs can induce high yield expansion of HSCs and be a substitute for the universal cocktail of SCF, TPO and FLT3-L in feeder-free culture.

A single-cell and feeder-free culture system for monkey embryonic stem cells.

Science.gov (United States)

Ono, Takashi; Suzuki, Yutaka; Kato, Yosuke; Fujita, Risako; Araki, Toshihiro; Yamashita, Tomoko; Kato, Hidemasa; Torii, Ryuzo; Sato, Naoya

2014-01-01

Primate pluripotent stem cells (PSCs), including embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), hold great potential for research and application in regenerative medicine and drug discovery. To maximize primate PSC potential, a practical system is required for generating desired functional cells and reproducible differentiation techniques. Much progress regarding their culture systems has been reported to date; however, better methods would still be required for their practical use, particularly in industrial and clinical fields. Here we report a new single-cell and feeder-free culture system for primate PSCs, the key feature of which is an originally formulated serum-free medium containing FGF and activin. In this culture system, cynomolgus monkey ESCs can be passaged many times by single-cell dissociation with traditional trypsin treatment and can be propagated with a high proliferation rate as a monolayer without any feeder cells; further, typical PSC properties and genomic stability can be retained. In addition, it has been demonstrated that monkey ESCs maintained in the culture system can be used for various experiments such as in vitro differentiation and gene manipulation. Thus, compared with the conventional culture system, monkey ESCs grown in the aforementioned culture system can serve as a cell source with the following practical advantages: simple, stable, and easy cell maintenance; gene manipulation; cryopreservation; and desired differentiation. We propose that this culture system can serve as a reliable platform to prepare primate PSCs useful for future research and application.

Stimulation of the proliferation of hemopoietic stem cells in irradiated bone marrow cell culture

International Nuclear Information System (INIS)

Mori, K.J.; Izumi, H.; Seto, A.

1981-01-01

Long-term hemopoiesis was established in bone marrow cell culture in vitro. This culture was shown to support the recovery proliferation of hemopoietic stem cells completely in vitro after irradiation. Hemopoietic stem cells were stimulated into proliferation in culture when normal bone marrow cells were overlayed on top of the irradiated adherent cell colonies. These results indicate that proliferation and differentiation of hemopoietic stem cells in vitro are also supported by stromahemopoietic cell interactions

Optimization of culture conditions to support long-term self-renewal of buffalo (Bubalus bubalis) embryonic stem cell-like cells.

Science.gov (United States)

Sharma, Ruchi; George, Aman; Kamble, Nitin Manchindra; Singh, Karn Pratap; Chauhan, Manmohan Singh; Singla, Suresh Kumar; Manik, Radhey Sham; Palta, Prabhat

2011-12-01

A culture system capable of sustaining self-renewal of buffalo embryonic stem (ES) cell-like cells in an undifferentiated state over a long period of time was developed. Inner cell masses were seeded on KO-DMEM+15% KO-serum replacer on buffalo fetal fibroblast feeder layer. Supplementation of culture medium with 5 ng/mL FGF-2 and 1000 IU/mL mLIF gave the highest (p<0.05) rate of primary colony formation. The ES cell-like cells' colony survival rate and increase in colony size were highest (p<0.05) following supplementation with FGF-2 and LIF compared to other groups examined. FGF-2 supplementation affected the quantitative expression of NANOG, SOX-2, ACTIVIN A, BMP 4, and TGFβ1, but not OCT4 and GREMLIN. Supplementation with SU5402, an FGFR inhibitor (≥20 μM) increased (p<0.05) the percentage of colonies that differentiated. FGFR1-3 and ERK1, K-RAS, E-RAS, and SHP-2, key signaling intermediates of FGF signaling, were detected in ES cell-like cells. Under culture conditions described, three ES cell lines were derived that, to date, have been maintained for 135, 95, and 85 passages for over 27, 19, and 17 months, respectively, whereas under other conditions examined, ES cell-like cells did not survive beyond passage 10. The ES cell-like cells were regularly monitored for expression of pluripotency markers and their potency to form embryoid bodies.

How do culture media influence in vitro perivascular cell behavior?

Science.gov (United States)

Huber, Birgit; Volz, Ann-Cathrin; Kluger, Petra Juliane

2015-12-01

Perivascular cells are multilineage cells located around the vessel wall and important for wall stabilization. In this study, we evaluated a stem cell media and a perivascular cell-specific media for the culture of primary perivascular cells regarding their cell morphology, doubling time, stem cell properties, and expression of cell type-specific markers. When the two cell culture media were compared to each other, perivascular cells cultured in the stem cell medium had a more elongated morphology and a faster doubling rate and cells cultured in the pericyte medium had a more typical morphology, with several filopodia, and a slower doubling rate. To evaluate stem cell properties, perivascular cells, CD146(-) cells, and mesenchymal stem cells (MSCs) were differentiated into the adipogenic, osteogenic, and chondrogenic lineages. It was seen that perivascular cells, as well as CD146(-) cells and MSCs, cultured in stem cell medium showed greater differentiation than cells cultured in pericyte-specific medium. The expression of pericyte-specific markers CD146, neural/glial antigen 2 (NG2), platelet-derived growth factor receptor-β (PDGFR-β), myosin, and α-smooth muscle actin (α-SMA) could be found in both pericyte cultures, as well as to varying amounts in CD146(-) cells, MSCs, and endothelial cells. The here presented work shows that perivascular cells can adapt to their in vitro environment and cell culture conditions influence cell functionality, such as doubling rate or differentiation behavior. Pericyte-specific markers were shown to be expressed also from cells other than perivascular cells. We can further conclude that CD146(+) perivascular cells are inhomogeneous cell population probably containing stem cell subpopulations, which are located perivascular around capillaries. © 2015 International Federation for Cell Biology.

Oxidative damage to DNA by diesel exhaust particle exposure in co-cultures of human lung epithelial cells and macrophages

DEFF Research Database (Denmark)

Jantzen, Kim; Roursgaard, Martin; Madsen, Claus Desler

2012-01-01

Studies in mono-culture of cells have shown that diesel exhaust particles (DEPs) increase the production of reactive oxygen species (ROS) and oxidative stress-related damage to DNA. However, the level of particle-generated genotoxicity may depend on interplay between different cell types, e.g. lung...... treatment with standard reference DEPs, SRM2975 and SRM1650b. The exposure to DEPs did not affect the colony-forming ability of A549 cells in co-culture with THP-1a cells. The DEPs generated DNA strand breaks and oxidatively damaged DNA, measured using the alkaline comet assay as formamidopyrimidine...... relationship between levels of respiration and ROS production. In conclusion, exposure of mono-cultured cells to DEPs generated oxidative stress to DNA, whereas co-cultures with macrophages had lower levels of oxidatively damaged DNA than A549 epithelial cells....

Cell culture arrays using micron-sized ferromagnetic ring-shaped thin films

Energy Technology Data Exchange (ETDEWEB)

Huang, Chen-Yu; Wei, Zung-Hang, E-mail: wei@pme.nthu.edu.tw [Department of Power Mechanical Engineering, National Tsing Hua University, Hsinchu City 300, Taiwan (China); Lai, Mei-Feng; Ger, Tzong-Rong [Institute of NanoEngineering and MicroSystems, National Tsing Hua University, Hsinchu City 300, Taiwan (China)

2015-05-07

Cell patterning has become an important technology for tissue engineering. In this research, domain walls are formed at the two ends of a ferromagnetic ring thin film after applying a strong external magnetic field, which can effectively attract magnetically labeled cells and control the position for biological cell. Magnetophoresis experiment was conducted to quantify the magnetic nanoparticle inside the cells. A ring-shaped magnetic thin films array was fabricated through photolithography. It is observed that magnetically labeled cells can be successfully attracted to the two ends of the ring-shaped magnetic thin film structure and more cells were attracted and further attached to the structures. The cells are co-cultured with the structure and kept proliferating; therefore, such ring thin film can be an important candidate for in-vitro biomedical chips or tissue engineering.

Cell culture arrays using micron-sized ferromagnetic ring-shaped thin films

International Nuclear Information System (INIS)

Huang, Chen-Yu; Wei, Zung-Hang; Lai, Mei-Feng; Ger, Tzong-Rong

2015-01-01

Cell patterning has become an important technology for tissue engineering. In this research, domain walls are formed at the two ends of a ferromagnetic ring thin film after applying a strong external magnetic field, which can effectively attract magnetically labeled cells and control the position for biological cell. Magnetophoresis experiment was conducted to quantify the magnetic nanoparticle inside the cells. A ring-shaped magnetic thin films array was fabricated through photolithography. It is observed that magnetically labeled cells can be successfully attracted to the two ends of the ring-shaped magnetic thin film structure and more cells were attracted and further attached to the structures. The cells are co-cultured with the structure and kept proliferating; therefore, such ring thin film can be an important candidate for in-vitro biomedical chips or tissue engineering

CD154 costimulated ovine primary B cells, a cell culture system that supports productive infection by bovine leukemia virus.

Science.gov (United States)

Van den Broeke, A; Cleuter, Y; Beskorwayne, T; Kerkhofs, P; Szynal, M; Bagnis, C; Burny, A; Griebel, P

2001-02-01

Bovine leukemia virus (BLV) is closely associated with the development of B-cell leukemia and lymphoma in cattle. BLV infection has also been studied extensively in an in vivo ovine model that provides a unique system for studying B-cell leukemogenesis. There is no evidence that BLV can directly infect ovine B cells in vitro, and there are no direct data regarding the oncogenic potential of the viral Tax transactivator in B cells. Therefore, we developed ovine B-cell culture systems to study the interaction between BLV and its natural target, the B cell. In this study, we used murine CD154 (CD40 ligand) and gamma-chain-common cytokines to support the growth of B cells isolated from ovine lymphoid tissues. Integrated provirus, extrachromosomal forms, and viral transcripts were detected in BLV-exposed populations of immature, rapidly dividing surface immunoglobulin M-positive B cells from sheep ileal Peyer's patches and also in activated mature B cells isolated from blood. Conclusive evidence of direct B-cell infection by BLV was obtained through the use of cloned B cells derived from sheep jejunal Peyer's patches. Finally, inoculation of sheep with BLV-infected cultures proved that infectious virus was shed from in vitro-infected B cells. Collectively, these data confirm that a variety of ovine B-cell populations can support productive infection by BLV. The development of ovine B-cell cultures permissive for BLV infection provides a controlled system for investigating B-cell leukemogenic processes and the pathogenesis of BLV infection.

Development of a microfluidic perfusion 3D cell culture system

Science.gov (United States)

Park, D. H.; Jeon, H. J.; Kim, M. J.; Nguyen, X. D.; Morten, K.; Go, J. S.

2018-04-01

Recently, 3-dimensional in vitro cell cultures have gained much attention in biomedical sciences because of the closer relevance between in vitro cell cultures and in vivo environments. This paper presents a microfluidic perfusion 3D cell culture system with consistent control of long-term culture conditions to mimic an in vivo microenvironment. It consists of two sudden expansion reservoirs to trap incoming air bubbles, gradient generators to provide a linear concentration, and microchannel mixers. Specifically, the air bubbles disturb a flow in the microfluidic channel resulting in the instability of the perfusion cell culture conditions. For long-term stable operation, the sudden expansion reservoir is designed to trap air bubbles by using buoyancy before they enter the culture system. The performance of the developed microfluidic perfusion 3D cell culture system was examined experimentally and compared with analytical results. Finally, it was applied to test the cytotoxicity of cells infected with Ewing’s sarcoma. Cell death was observed for different concentrations of H2O2. For future work, the developed microfluidic perfusion 3D cell culture system can be used to examine the behavior of cells treated with various drugs and concentrations for high-throughput drug screening.

Cardiac Cells Beating in Culture: A Laboratory Exercise

Science.gov (United States)

Weaver, Debora

2007-01-01

This article describes how to establish a primary tissue culture, where cells are taken directly from an organ of a living animal. Cardiac cells are taken from chick embryos and transferred to culture dishes. These cells are not transformed and therefore have a limited life span. However, the unique characteristics of cardiac cells are maintained…

Improved endothelial cell seeding with cultured cells and fibronectin-coated grafts

International Nuclear Information System (INIS)

Seeger, J.M.; Klingman, N.

1985-01-01

A possible approach to the low seeding efficiency of endothelial cells into prosthetic grafts is to increase the number of cells to be seeded in cell culture and improve seeding efficiency by graft precoating with fibronectin. The effect of cell culture on cell adhesion is unknown, however, and fibronectin also binds fibrin, which may increase the thrombogenicity of the graft luminal surface. To investigate these questions, freshly harvested canine jugular vein endothelial cells from six animals and similar cells harvested from six primary and eight secondary cell cultures were labeled with 111 Indium and seeded into 5 cm, 4 mm PTFE grafts coated with fibronectin, using similar uncoated PTFE grafts as controls. Platelet accumulation and distribution on six similar coated and uncoated grafts placed in canine carotid, external jugular arterial venous shunts for 2 hr were also determined using autogenous 111 Indium-labeled platelets. Significant differences between group means were determined using the paired Student's t test. Results reveal that seeding efficiency is significantly better in all groups of coated grafts compared to uncoated grafts (P less than 0.01). Cells derived from cell culture also had significantly higher seeding efficiencies than freshly harvested cells when seeded into coated grafts (P less than 0.05) and tended to have higher seeding efficiencies than harvested cells when seeded into uncoated grafts (P = 0.53). Fibronectin coating increased mean platelet accumulation on the entire graft luminal surface, but not to a statistically significant degree (P greater than 0.1). Whether this increased seeding efficiency will improve graft endothelialization remains to be investigated

Dynamic cell culture system: a new cell cultivation instrument for biological experiments in space

Science.gov (United States)

Gmunder, F. K.; Nordau, C. G.; Tschopp, A.; Huber, B.; Cogoli, A.

1988-01-01

The prototype of a miniaturized cell cultivation instrument for animal cell culture experiments aboard Spacelab is presented (Dynamic cell culture system: DCCS). The cell chamber is completely filled and has a working volume of 200 microliters. Medium exchange is achieved with a self-powered osmotic pump (flowrate 1 microliter h-1). The reservoir volume of culture medium is 230 microliters. The system is neither mechanically stirred nor equipped with sensors. Hamster kidney (Hak) cells growing on Cytodex 3 microcarriers were used to test the biological performance of the DCCS. Growth characteristics in the DCCS, as judged by maximal cell density, glucose consumption, lactic acid secretion and pH, were similar to those in cell culture tubes.

Quantitative volumetric Raman imaging of three dimensional cell cultures

KAUST Repository

Kallepitis, Charalambos; Bergholt, Mads S.; Mazo, Manuel M.; Leonardo, Vincent; Skaalure, Stacey C.; Maynard, Stephanie A.; Stevens, Molly M.

2017-01-01

in conventional cell culture systems and mesenchymal stem cells inside biomimetic hydrogels that supplied a 3D cell culture environment. We demonstrate visualization and quantification of fine details in cell shape, cytoplasm, nucleus, lipid bodies

System-level modeling and simulation of the cell culture microfluidic biochip ProCell

DEFF Research Database (Denmark)

Minhass, Wajid Hassan; Pop, Paul; Madsen, Jan

2010-01-01

Microfluidic biochips offer a promising alternative to a conventional biochemical laboratory. There are two technologies for the microfluidic biochips: droplet-based and flow-based. In this paper we are interested in flow-based microfluidic biochips, where the liquid flows continuously through pre......-defined micro-channels using valves and pumps. We present an approach to the system-level modeling and simulation of a cell culture microfluidic biochip called ProCell, Programmable Cell Culture Chip. ProCell contains a cell culture chamber, which is envisioned to run 256 simultaneous experiments (viewed...

Culturing of PC12 Cells, Neuronal Cells, Astrocytes Cultures and Brain Slices in an Open Microfluidic System

DEFF Research Database (Denmark)

Al Atraktchi, Fatima Al-Zahraa; Bakmand, Tanya; Rømer Sørensen, Ane

The brain is the center of the nervous system, where serious neurodegenerative diseases such as Parkinson’s, Alzheimer’s and Huntington’s are products of functional loss in the neural cells (1). Typical techniques used to investigate these diseases lack precise control of the cellular surroundings......, in addition to isolating the neural tissue from nutrient delivery and to creating unwanted gradients (2). This means that typical techniques used to investigate neurodegenerative diseases cannot mimic in vivo conditions, as closely as desired. We have developed a novel microfluidic system for culturing PC12...... cells, neuronal cells, astrocytes cultures and brain slices. The microfluidic system provides efficient nutrient delivery, waste removal, access to oxygen, fine control over the neurochemical environment and access to modern microscopy. Additionally, the setup consists of an in vitro culturing...

Photovoltaic cell module and method of forming

Science.gov (United States)

Howell, Malinda; Juen, Donnie; Ketola, Barry; Tomalia, Mary Kay

2017-12-12

A photovoltaic cell module, a photovoltaic array including at least two modules, and a method of forming the module are provided. The module includes a first outermost layer and a photovoltaic cell disposed on the first outermost layer. The module also includes a second outermost layer disposed on the photovoltaic cell and sandwiching the photovoltaic cell between the second outermost layer and the first outermost layer. The method of forming the module includes the steps of disposing the photovoltaic cell on the first outermost layer, disposing a silicone composition on the photovoltaic cell, and compressing the first outermost layer, the photovoltaic cell, and the second layer to form the photovoltaic cell module.

Maintenance of mesenchymal stem cells culture due to the cells with reduced attachment rate

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Shuvalova N. S.

2013-01-01

Full Text Available Aim. The classic detachment techniques lead to changes in cells properties. We offer a simple method of cultivating the population of cells that avoided an influence on the surface structures. Methods. Mesenchymal stem cells (MSC from human umbilical cord matrix were obtained and cultivated in standard conditions. While substituting the culture media by a fresh portion, the conditioned culture medium, where the cells were maintained for three days, was transferred to other culture flacks with addition of serum and growth factors. Results. In the flacks, one day after medium transfer, we observed attached cells with typical MSC morphology. The cultures originated from these cells had the same rate of surface markers expression and clonogenic potential as those replated by standard methods. Conclusions. MSC culture, derived by preserving the cells with reduced attachment ability, actually has the properties of «parent» passage. Using this method with accepted techniques of cells reseeding would allow maintaining the cells that avoided an impact on the cell surface proteins.

Calcium exchange, structure, and function in cultured adult myocardial cells

International Nuclear Information System (INIS)

Langer, G.A.; Frank, J.S.; Rich, T.L.; Orner, F.B.

1987-01-01

Cells digested from adult rat heart and cultured for 14 days demonstrate all the structural elements, in mature form, associated with the process of excitation-contraction (EC) coupling. The transverse tubular (TT) system is well developed with an extensive junctional sarcoplasmic reticulum (JSR). In nonphosphate-containing buffer contraction of the cells is lost as rapidly as zero extracellular Ca concentration ([Ca] 0 ) solution is applied and a negative contraction staircase is produced on increase of stimulation frequency. Structurally and functionally the cells have the characteristics of adult cells in situ. 45 Ca exchange and total 45 Ca measurement in N-2-hydroxyethylpiperazine N'-2-ethanesulfonic acid (HEPES)-buffered perfusate define three components of cellular Ca: 1) a rapidly exchangeable component accounting for 36% of total Ca, 2) a slowly exchangeable component (t/sub 1/2/ 53 min) accounting for 7% total Ca, and 3) the remaining 57% cellular Ca is inexchangeable (demonstrates no significant exchange within 60 min). The slowly exchangeable component can be increased 10-fold within 60 min by addition of phosphate to the perfusate. The Ca distribution and exchange characteristics are little different from those of 3-day cultures of neonatal rat heart previously studied. The results suggest that the cells are representative of adult cells in situ and that both sarcolemmal-bound and sarcoplasmic reticular Ca contribute to the component of Ca that is rapidly exchangeable

Evaluation of the osteogenic differentiation of gingiva-derived stem cells grown on culture plates or in stem cell spheroids: Comparison of two- and three-dimensional cultures.

Science.gov (United States)

Lee, Sung-Il; Ko, Youngkyung; Park, Jun-Beom

2017-09-01

Three-dimensional cell culture systems provide a convenient in vitro model for the study of complex cell-cell and cell-matrix interactions in the absence of exogenous substrates. The current study aimed to evaluate the osteogenic differentiation potential of gingiva-derived stem cells cultured in two-dimensional or three-dimensional systems. To the best of our knowledge, the present study is the first to compare the growth of gingiva-derived stem cells in monolayer culture to a three-dimensional culture system with microwells. For three-dimensional culture, gingiva-derived stem cells were isolated and seeded into polydimethylsiloxane-based concave micromolds. Alkaline phosphatase activity and alizarin red S staining assays were then performed to evaluate osteogenesis and the degree of mineralization, respectively. Stem cell spheroids had a significantly increased level of alkaline phosphatase activity and mineralization compared with cells from the two-dimensional culture. In addition, an increase in mineralized deposits was observed with an increase in the loading cell number. The results of present study indicate that gingiva-derived stem cell spheroids exhibit an increased osteogenic potential compared with stem cells from two-dimensional culture. This highlights the potential of three-dimensional culture systems using gingiva-derived stem cells for regenerative medicine applications requiring stem cells with osteogenic potential.

A novel three-dimensional cell culture method enhances antiviral drug screening in primary human cells.

Science.gov (United States)

Koban, Robert; Neumann, Markus; Daugs, Aila; Bloch, Oliver; Nitsche, Andreas; Langhammer, Stefan; Ellerbrok, Heinz

2018-02-01

Gefitinib is a specific inhibitor of the epidermal growth factor receptor (EGFR) and FDA approved for treatment of non-small cell lung cancer. In a previous study we could show the in vitro efficacy of gefitinib for treatment of poxvirus infections in monolayer (2D) cultivated cell lines. Permanent cell lines and 2D cultures, however, are known to be rather unphysiological; therefore it is difficult to predict whether determined effective concentrations or the drug efficacy per se are transferable to the in vivo situation. 3D cell cultures, which meanwhile are widely distributed across all fields of research, are a promising tool for more predictive in vitro investigations of antiviral compounds. In this study the spreading of cowpox virus and the antiviral efficacy of gefitinib were analyzed in primary human keratinocytes (NHEK) grown in a novel 3D extracellular matrix-based cell culture model and compared to the respective monolayer culture. 3D-cultivated NHEK grew in a polarized and thus a more physiological manner with altered morphology and close cell-cell contact. Infected cultures showed a strongly elevated sensitivity towards gefitinib. EGFR phosphorylation, cell proliferation, and virus replication were significantly reduced in 3D cultures at gefitinib concentrations which were at least 100-fold lower than those in monolayer cultures and well below the level of cytotoxicity. Our newly established 3D cell culture model with primary human cells is an easy-to-handle alternative to conventional monolayer cell cultures and previously described more complex 3D cell culture systems. It can easily be adapted to other cell types and a broad spectrum of viruses for antiviral drug screening and many other aspects of virus research under more in vivo-like conditions. In consequence, it may contribute to a more targeted realization of necessary in vivo experiments. Copyright © 2017 Elsevier B.V. All rights reserved.

Dependence of cell adhesion on extracellular matrix materials formed on pore bridge boundaries by nanopore opening and closing geometry.

Science.gov (United States)

Kim, Sueon; Han, Dong Yeol; Chen, Zhenzhong; Lee, Won Gu

2018-04-30

In this study, we report experimental results for characterization of the growth and formation of pore bridge materials that modified the adhesion structures of cells cultured on nanomembranes with opening and closing geometry. To perform the proof-of-concept experiments, we fabricated two types of anodized alumina oxide substrates with single-sided opening (i.e., one side open, but closed at the other side) and double-sided opening (i.e., both sides open). In our experiment, we compared the densities of pores formed and of bridge materials which differently act as connective proteins depending on the size of pores. The results show that the pore opening geometry can be used to promote the net contact force between pores, resulting in the growth and formation of pore bridge materials before and after cell culture. The results also imply that the bridge materials can be used to attract the structural protrusion of filopodia that can promote the adhesion of cell-to-cell and cell-to-pore bridge. It is observed that the shape and size of cellular structures of filopodia depend on the presence of pore bridge materials. Overall, this observation brought us a significant clue that cells cultured on nanopore substrates would change the adhesion property depending on not only the formation of nanopores formed on the surface of topological substrates, but also that of pore bridge materials by its morphological growth.

Mesenchymal stem cells enhance the metastasis of 3D-cultured hepatocellular carcinoma cells

International Nuclear Information System (INIS)

Liu, Chang; Liu, Yang; Xu, Xiao-xi; Guo, Xin; Sun, Guang-wei; Ma, Xiao-jun

2016-01-01

Accumulating evidences have demonstrated that mesenchymal stem cells (MSC) could be recruited to the tumor microenvironment. Umbilical cord mesenchymal stem cells (UCMSC) were attractive vehicles for delivering therapeutic agents against cancer. Nevertheless, the safety of UCMSC in the treatment of tumors including hepatocellular carcinoma (HCC) was still undetermined. In this study, an in vitro co-culture system was established to evaluate the effect of UCMSC on the cell growth, cancer stem cell (CSC) characteristics, drug resistance, metastasis of 3D-cultured HCC cells, and the underlying mechanism was also investigated. It was found that after co-cultured with UCMSC, the metastatic ability of 3D-cultured HCC cells was significantly enhanced as indicated by up-regulation of matrix metalloproteinase (MMP), epithelial-mesenchymal transition (EMT)-related genes, and migration ability. However, cell growth, drug resistance and CSC-related gene expression of HCC cells were not affected by UCMSC. Moreover, EMT was reversed, MMP-2 expression was down-regulated, and migration ability of HCC cell was significantly inhibited when TGF-β receptor inhibitor SB431542 was added into the co-culture system. Therefore, these data indicated that UCMSC could significantly enhance the tumor cell metastasis, which was due to the EMT of HCC cells induced by TGF-β. The online version of this article (doi:10.1186/s12885-016-2595-4) contains supplementary material, which is available to authorized users

Primary Human Uterine Leiomyoma Cell Culture Quality Control: Some Properties of Myometrial Cells Cultured under Serum Deprivation Conditions in the Presence of Ovarian Steroids.

Science.gov (United States)

Bonazza, Camila; Andrade, Sheila Siqueira; Sumikawa, Joana Tomomi; Batista, Fabrício Pereira; Paredes-Gamero, Edgar J; Girão, Manoel J B C; Oliva, Maria Luiza V; Castro, Rodrigo Aquino

2016-01-01

Cell culture is considered the standard media used in research to emulate the in vivo cell environment. Crucial in vivo experiments cannot be conducted in humans and depend on in vitro methodologies such as cell culture systems. However, some procedures involving the quality control of cells in culture have been gradually neglected by failing to acknowledge that primary cells and cell lines change over time in culture. Thus, we report methods based on our experience for monitoring primary cell culture of human myometrial cells derived from uterine leiomyoma. We standardized the best procedure of tissue dissociation required for the study of multiple genetic marker systems that include species-specific antigens, expression of myofibroblast or myoblast markers, growth curve, serum deprivation, starvation by cell cycle synchronization, culture on collagen coated plates, and 17 β-estradiol (E2) and progesterone (P4) effects. The results showed that primary myometrial cells from patients with uterine leiomyoma displayed myoblast phenotypes before and after in vitro cultivation, and leiomyoma cells differentiated into mature myocyte cells under the appropriate differentiation-inducing conditions (serum deprivation). These cells grew well on collagen coated plates and responded to E2 and P4, which may drive myometrial and leiomyoma cells to proliferate and adhere into a focal adhesion complex involvement in a paracrine manner. The establishment of these techniques as routine procedures will improve the understanding of the myometrial physiology and pathogenesis of myometrium-derived diseases such as leiomyoma. Mimicking the in vivo environment of fibrotic conditions can prevent false results and enhance results that are based on cell culture integrity.

Expression of smooth muscle and non-muscle myosin heavy chain isoforms in cultured vascular smooth muscle cells

International Nuclear Information System (INIS)

Rovner, A.S.; Murphy, R.A.; Owens, G.K.

1986-01-01

Immunocytochemical studies of cultured smooth muscle cells (SMCs) have disagreed on the nature of myosin expression. This investigation was undertaken to test for the presence of heterogeneous myosin heavy chain (MHC) isoforms in cell culture as a possible explanation for these results. Previously, Rovner et al. detected two MHCs in intact smooth muscles which differed in molecular weight by ca. 4000 daltons (SM1 and SM2) using a 3-4% acrylamide gradient SDS gel system. When sub-confluent primary cultures of rat aorta SMCs were assayed by this system, SM1 and SM2 were seen, along with large amounts of a third, unique MHC, NM, which closely resembled the MHC from human platelet in size and antigenicity. Data from 35 S-methionine autoradiograms showed that the log growth phase SMC cultures were producing almost exclusively NM, but the growth arrest, post-confluent cultures synthesized increased relative amounts of the SM MHC forms and contained comparable amounts of SM1, SM2, and NM. The same patterns of MHC synthesis were seen in sub-passaged SMCs. The expression of the SM-specific forms of myosin in quiescent, post-confluent cultures parallels that of smooth muscle actin suggesting that density induced growth arrest promotes cytodifferentiation in cultured vascular SMCs

Regeneration of hemopoietic precursor cells in spleen organ cultures from irradiated mice: influence of genotype of cells injected and of the spleen microenvironment

International Nuclear Information System (INIS)

von Melchner, H.; Lieschke, G.J.

1981-01-01

The regeneration of hemopoietic precursor cells (colony-forming cells, CFC) was monitored in spleen organ cultures from lethally irradiated mice injected with 10(7) normal syngeneic or allogeneic bone marrow cells. The important role of the microenvironment in supporting hemopoiesis was confirmed by the failure of mutant S1/S1d spleens to support CFC regeneration in organ cultures. However, the extent and quality of the CFC regeneration was clearly dependent on the genetic properties of the injected cells. Evidence for this was obtained from the regeneration patterns of various CFC types in organ cultured spleens derived from different mouse donor-recipient strain combinations (CBA/CBA, CBA/C57BL, CBA/BALB/c, C57BL/C57BL, C57BL/CBA, C57BL/BALB/c) that maintained the differences in the bone marrow frequency of various CFC types characteristic of the donor strain

Digital microfluidics for automated hanging drop cell spheroid culture.

Science.gov (United States)

Aijian, Andrew P; Garrell, Robin L

2015-06-01

Cell spheroids are multicellular aggregates, grown in vitro, that mimic the three-dimensional morphology of physiological tissues. Although there are numerous benefits to using spheroids in cell-based assays, the adoption of spheroids in routine biomedical research has been limited, in part, by the tedious workflow associated with spheroid formation and analysis. Here we describe a digital microfluidic platform that has been developed to automate liquid-handling protocols for the formation, maintenance, and analysis of multicellular spheroids in hanging drop culture. We show that droplets of liquid can be added to and extracted from through-holes, or "wells," and fabricated in the bottom plate of a digital microfluidic device, enabling the formation and assaying of hanging drops. Using this digital microfluidic platform, spheroids of mouse mesenchymal stem cells were formed and maintained in situ for 72 h, exhibiting good viability (>90%) and size uniformity (% coefficient of variation <10% intraexperiment, <20% interexperiment). A proof-of-principle drug screen was performed on human colorectal adenocarcinoma spheroids to demonstrate the ability to recapitulate physiologically relevant phenomena such as insulin-induced drug resistance. With automatable and flexible liquid handling, and a wide range of in situ sample preparation and analysis capabilities, the digital microfluidic platform provides a viable tool for automating cell spheroid culture and analysis. © 2014 Society for Laboratory Automation and Screening.

Protection of cultured mammalian cells by rebamipide

International Nuclear Information System (INIS)

Antoku, Shigetoshi; Aramaki, Ryoji; Tanaka, Hisashi; Kusumoto, Naotoshi.

1997-01-01

Rebamipide which is used as a drug for gastritis and stomach ulcer has large capability for OH radical scavenging. It is expected that rebamipide has protective effect against ionizing radiations. The present paper deals with protective effect of rebamipide for cultured mammalian cells exposed to ionizing radiations. As rebamipide is insoluble in water, three solvents were used to dissolve. Rebamipide dissolved in dimethyl sulfoxide (DMSO), dimethyl formamide (DMFA) and 0.02 N NaOH was added to the cells in Eagle's minimum essential medium (MEM) supplemented with 10% fetal calf serum and the cells were irradiated with X-rays. After irradiation, the cells were trypsinized, plated in MEM with 10% fetal calf serum and incubated for 7 days in a CO 2 incubator to form colonies. Rebamipide dissolved in 0.02 N NaOH exhibited the protective effect expected its OH radical scavenging capability. However, the protective effect of rebamipide dissolved in DMSO was about half of that expected by its radical scavenging capability and that of rebamipide dissolved in DMFA was not observed. Uptake of rebamipide labeled with 14 C increased with increasing contact time with rebamipide. These rebamipide mainly distributed in nucleus rather than cytoplasm. (author)

The impact of cell culture equipment on energy loss.

Science.gov (United States)

Davies, Lleucu B; Kiernan, Michael N; Bishop, Joanna C; Thornton, Catherine A; Morgan, Gareth

2014-01-01

Light energy of discrete wavelengths supplied via lasers and broadband intense pulsed light have been used therapeutically for many years. In vitro models complement clinical studies, especially for the elucidation of underlying mechanisms of action. Clarification that light energy reaches the cells is necessary when developing protocols for the treatment of cells using in vitro models. Few studies report on energy loss in cell culture equipment. The ability of energy from light with therapeutic potential to reach cells in culture needs to be determined; this includes determining the proportion of light energy lost within standard cell culture media and cell culture vessels. The energy absorption of cell culture media, with/without the pH indicator dye phenol red, and the loss of energy within different plastics and glassware used typically for in vitro cell culture were investigated using intense pulsed light and a yellow pulsed dye laser. Media containing phenol red have a distinctive absorption peak (560 nm) absent in phenol red-free media and restored by the addition of phenol red. For both light sources, energy loss was lowest in standard polystyrene tissue culture flasks or multi-well plates and highest in polypropylene vessels or glass tubes. The effects of phenol red-free media on the absorption of energy varied with the light source used. Phenol red-free media are the media of choice; polystyrene vessels with flat surfaces such as culture flasks or multi-well plates should be used in preference to polypropylene or glass vessels.

Thermoresponsive microgels containing trehalose as soft matrices for 3D cell culture.

Science.gov (United States)

Burek, Małgorzata; Waśkiewicz, Sylwia; Lalik, Anna; Student, Sebastian; Bieg, Tadeusz; Wandzik, Ilona

2017-01-31

A series of thermoresponsive glycomicrogels with trehalose in the cross-links or with trehalose in the cross-links and as pending moieties was synthesized. These materials were obtained by surfactant-free precipitation copolymerization of N-isopropylacrylamide and various amounts of trehalose monomers. The resultant particles showed a spherical shape and a submicrometer hydrodynamic size with a narrow size distribution. At 25 °C, glycomicrogels in solutions with physiological ionic strength formed stable colloids, which further gelled upon heating to physiological temperature forming a macroscopic hydrogel with an interconnected porous structure. These extremely soft matrices with dynamic storage modulus in the range of 9-70 Pa were examined in 3D culture systems for HeLa cell culture in comparison to traditional 2D mode. They showed relatively low syneresis over time, especially when glycomicrogels with a high content of hydrophilic trehalose were used as building blocks. An incorporated pending trehalose composed of two α,α'-1,1'-linked d-glucose moieties was used with the intention of providing multivalent interactions with glucose transporters (GLUTs) expressed on the cell surface. A better cell viability was observed when a soft hydrogel with the highest content of trehalose and the lowest syneresis was used as a matrix compared to a 2D control assay.

Identification of differences in gene expression in primary cell cultures of human endometrial epithelial cells and trophoblast cells following their interaction

DEFF Research Database (Denmark)

Høgh, Mette; Islin, Henrik; Møller, Charlotte

2006-01-01

The interaction between the cell types was simulated in vitro by growing primary cell cultures of human endometrial epithelial cells and trophoblast cells together (co-culture) and separately (control cultures). Gene expression in the cell cultures was compared using the Differential Display method and confirmed...

Mechanisms of cross-suppression of TNP-specific plaque forming cell responses by TMA-specific first-order T suppressor factor

Energy Technology Data Exchange (ETDEWEB)

Jendrisak, G.S.; Bellone, C.J.

1986-03-05

The addition of hybridoma-derived phenyltrimethylammonium (TMA)-specific first-order T suppressor factor (TsF/sub 1/) into cultures containing Brucella abortus coupled with the TMA and trinitrophenol haptens (TMA-BA-TNP) results in the cross-suppression of TNP-specific plaque forming cell (PFC) responses. The suppression mediated by TMA-TsF/sub 1/ is dependent on the presence of T cells and specific antigen (TMA). Subculturing of whole spleen cells with TMA-TsF/sub 1/ and specific soluble antigen (TMA-BSA) is able to induce suppressor T cells which cross-suppress the TNP-specific PFC of spleen cell cultures stimulated with TMA-BA-TNP in an antigen (TMA)-dependent manner at the effector phase of the response. The effector acting T suppressor cells (Tse) are nylon wool nonadherent and appears to require whole spleen cells in responding cultures for suppression, suggesting that the target of the Tse is not the TNP-specific B cell. The authors are presently characterizing the mechanisms of cross-suppression by TMA-TsF/sub 1/ and Tse utilizing the described primary in vitro antibody assay.

Optimization of high grade glioma cell culture from surgical specimens for use in clinically relevant animal models and 3D immunochemistry.

Science.gov (United States)

Hasselbach, Laura A; Irtenkauf, Susan M; Lemke, Nancy W; Nelson, Kevin K; Berezovsky, Artem D; Carlton, Enoch T; Transou, Andrea D; Mikkelsen, Tom; deCarvalho, Ana C

2014-01-07

Glioblastomas, the most common and aggressive form of astrocytoma, are refractory to therapy, and molecularly heterogeneous. The ability to establish cell cultures that preserve the genomic profile of the parental tumors, for use in patient specific in vitro and in vivo models, has the potential to revolutionize the preclinical development of new treatments for glioblastoma tailored to the molecular characteristics of each tumor. Starting with fresh high grade astrocytoma tumors dissociated into single cells, we use the neurosphere assay as an enrichment method for cells presenting cancer stem cell phenotype, including expression of neural stem cell markers, long term self-renewal in vitro, and the ability to form orthotopic xenograft tumors. This method has been previously proposed, and is now in use by several investigators. Based on our experience of dissociating and culturing 125 glioblastoma specimens, we arrived at the detailed protocol we present here, suitable for routine neurosphere culturing of high grade astrocytomas and large scale expansion of tumorigenic cells for preclinical studies. We report on the efficiency of successful long term cultures using this protocol and suggest affordable alternatives for culturing dissociated glioblastoma cells that fail to grow as neurospheres. We also describe in detail a protocol for preserving the neurospheres 3D architecture for immunohistochemistry. Cell cultures enriched in CSCs, capable of generating orthotopic xenograft models that preserve the molecular signatures and heterogeneity of GBMs, are becoming increasingly popular for the study of the biology of GBMs and for the improved design of preclinical testing of potential therapies.

Youth Culture and Cell Phone

Directory of Open Access Journals (Sweden)

mohammad saeed zokaei

2009-11-01

Full Text Available Iranian youth’s leisure culture has been immediately affected by the digital media culture. As a communicative media, cell phone has crossed borders of youth norms and identity; and in addition to facilitating their communication, has changed its patterns. Applying Bourdieu’s concepts of habitus and field, and relied on the qualitative and quantitative data gathered from the mobile youth users, the present study argues that mobile has produced a new field in which youth’s opportunities for leisure, entertainment, communication, and independence have extended. In addition, cell phone has facilitated and compensated for some defects in public sphere, and therefore empowered youth agency, individuality, and power. Despite this strengthening, cell phone does not cross borders of gender and class differences, or the levels of social capital.

A method for autoradiographic studies of single clones of plaque forming cells

International Nuclear Information System (INIS)

Andersen, V.; Lefkovits, I.; Rigshospitalet, Copenhagen

1977-01-01

By limiting dilution of B lymphocytes from spleens of immunized mice, microcultures were obtained that contained only one clone of plaque forming cells (PFC). The cultured cells were labelled with [ 14 C]thymidine for varying period of time. Plaques were obtained in monolayers of sheep erythrocytes in plastic dishes. After fixation with glutaraldehyde, the bottoms of the dishes were stripped off and autoradiograms prepared. By this method, it is possible to determine the proportion of labelled PFC within a given clone and to quantitate the incorporation of label. The method described can be applied to study the incorporation of other labelled molecules and for cytochemical investigations

Matrix production and organization by endothelial colony forming cells in mechanically strained engineered tissue constructs.

Directory of Open Access Journals (Sweden)

Nicky de Jonge

Full Text Available AIMS: Tissue engineering is an innovative method to restore cardiovascular tissue function by implanting either an in vitro cultured tissue or a degradable, mechanically functional scaffold that gradually transforms into a living neo-tissue by recruiting tissue forming cells at the site of implantation. Circulating endothelial colony forming cells (ECFCs are capable of differentiating into endothelial cells as well as a mesenchymal ECM-producing phenotype, undergoing Endothelial-to-Mesenchymal-transition (EndoMT. We investigated the potential of ECFCs to produce and organize ECM under the influence of static and cyclic mechanical strain, as well as stimulation with transforming growth factor β1 (TGFβ1. METHODS AND RESULTS: A fibrin-based 3D tissue model was used to simulate neo-tissue formation. Extracellular matrix organization was monitored using confocal laser-scanning microscopy. ECFCs produced collagen and also elastin, but did not form an organized matrix, except when cultured with TGFβ1 under static strain. Here, collagen was aligned more parallel to the strain direction, similar to Human Vena Saphena Cell-seeded controls. Priming ECFC with TGFβ1 before exposing them to strain led to more homogenous matrix production. CONCLUSIONS: Biochemical and mechanical cues can induce extracellular matrix formation by ECFCs in tissue models that mimic early tissue formation. Our findings suggest that priming with bioactives may be required to optimize neo-tissue development with ECFCs and has important consequences for the timing of stimuli applied to scaffold designs for both in vitro and in situ cardiovascular tissue engineering. The results obtained with ECFCs differ from those obtained with other cell sources, such as vena saphena-derived myofibroblasts, underlining the need for experimental models like ours to test novel cell sources for cardiovascular tissue engineering.

Primary Human Uterine Leiomyoma Cell Culture Quality Control: Some Properties of Myometrial Cells Cultured under Serum Deprivation Conditions in the Presence of Ovarian Steroids.

Directory of Open Access Journals (Sweden)

Camila Bonazza

Full Text Available Cell culture is considered the standard media used in research to emulate the in vivo cell environment. Crucial in vivo experiments cannot be conducted in humans and depend on in vitro methodologies such as cell culture systems. However, some procedures involving the quality control of cells in culture have been gradually neglected by failing to acknowledge that primary cells and cell lines change over time in culture. Thus, we report methods based on our experience for monitoring primary cell culture of human myometrial cells derived from uterine leiomyoma. We standardized the best procedure of tissue dissociation required for the study of multiple genetic marker systems that include species-specific antigens, expression of myofibroblast or myoblast markers, growth curve, serum deprivation, starvation by cell cycle synchronization, culture on collagen coated plates, and 17 β-estradiol (E2 and progesterone (P4 effects. The results showed that primary myometrial cells from patients with uterine leiomyoma displayed myoblast phenotypes before and after in vitro cultivation, and leiomyoma cells differentiated into mature myocyte cells under the appropriate differentiation-inducing conditions (serum deprivation. These cells grew well on collagen coated plates and responded to E2 and P4, which may drive myometrial and leiomyoma cells to proliferate and adhere into a focal adhesion complex involvement in a paracrine manner. The establishment of these techniques as routine procedures will improve the understanding of the myometrial physiology and pathogenesis of myometrium-derived diseases such as leiomyoma. Mimicking the in vivo environment of fibrotic conditions can prevent false results and enhance results that are based on cell culture integrity.

3D cell culture to determine in vitro biocompatibility of bioactive glass in association with chitosan.

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Bédouin, Y; Pellen Mussi, P; Tricot-Doleux, S; Chauvel-Lebret, D; Auroy, P; Ravalec, X; Oudadesse, H; Perez, F

2015-01-01

This study reports the in vitro biocompatibility of a composite biomaterial composed of 46S6 bioactive glass in association with chitosan (CH) by using 3D osteoblast culture of SaOS2. The 46S6 and CH composite (46S6-CH) forms small hydroxyapatite crystals on its surface after only three days immersion in the simulated body fluid. For 2D osteoblast culture, a significant increase in cell proliferation was observed after three days of contact with 46S6 or 46S6-CH-immersed media. After six days, 46S6-CH led to a significant increase in cell proliferation (128%) compared with pure 46S6 (113%) and pure CH (122%). For 3D osteoblast culture, after six days of culture, there was an increase in gene expression of markers of the early osteoblastic differentiation (RUNX2, ALP, COL1A1). Geometric structures corresponding to small apatite clusters were observed by SEM on the surface of the spheroids cultivated with 46S6 or 46S6-CH-immersed media. We showed different cellular responses depending on the 2D and 3D cell culture model. The induction of osteoblast differentiation in the 3D cell culture explained the differences of cell proliferation in contact with 46S6, CH or 46S6-CH-immersed media. This study confirmed that the 3D cell culture model is a very promising tool for in vitro biological evaluation of bone substitutes' properties.

Hematopoietic Stem and Progenitor Cell Expansion in Contact with Mesenchymal Stromal Cells in a Hanging Drop Model Uncovers Disadvantages of 3D Culture.

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Schmal, Olga; Seifert, Jan; Schäffer, Tilman E; Walter, Christina B; Aicher, Wilhelm K; Klein, Gerd

2016-01-01

Efficient ex vivo expansion of hematopoietic stem cells with a concomitant preservation of stemness and self-renewal potential is still an unresolved ambition. Increased numbers of methods approaching this issue using three-dimensional (3D) cultures were reported. Here, we describe a simplified 3D hanging drop model for the coculture of cord blood-derived CD34(+) hematopoietic stem and progenitor cells (HSPCs) with bone marrow-derived mesenchymal stromal cells (MSCs). When seeded as a mixed cell suspension, MSCs segregated into tight spheroids. Despite the high expression of niche-specific extracellular matrix components by spheroid-forming MSCs, HSPCs did not migrate into the spheroids in the initial phase of coculture, indicating strong homotypic interactions of MSCs. After one week, however, HSPC attachment increased considerably, leading to spheroid collapse as demonstrated by electron microscopy and immunofluorescence staining. In terms of HSPC proliferation, the conventional 2D coculture system was superior to the hanging drop model. Furthermore, expansion of primitive hematopoietic progenitors was more favored in 2D than in 3D, as analyzed in colony-forming assays. Conclusively, our data demonstrate that MSCs, when arranged with a spread (monolayer) shape, exhibit better HSPC supportive qualities than spheroid-forming MSCs. Therefore, 3D systems are not necessarily superior to traditional 2D culture in this regard.

Cell culture density affects the proliferation activity of human adipose tissue stem cells.

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Kim, Dae Seong; Lee, Myoung Woo; Ko, Young Jong; Chun, Yong Hoon; Kim, Hyung Joon; Sung, Ki Woong; Koo, Hong Hoe; Yoo, Keon Hee

2016-01-01

In this study, we investigated the effect of cell density on the proliferation activity of human mesenchymal stem cells (MSCs) derived from adipose tissue (AT-MSCs) over time in culture. Passage #4 (P4) and #12 (P12) AT-MSCs from two donors were plated at a density of 200 (culture condition 1, CC1) or 5000 (culture condition 2, CC2) cells cm(-2) . After 7 days of incubation, P4 and P12 AT-MSCs cultured in CC1 were thin and spindle-shaped, whereas those cultured in CC2 had extensive cell-to-cell contacts and an expanded cell volume. In addition, P4 and P12 AT-MSCs in CC1 divided more than three times, while those in CC2 divided less than once on average. Flow cytometric analysis using 5(6)-carboxyfluorescein diacetate N-succinimidyl ester dye showed that the fluorescence intensity of AT-MSCs was lower in CC1 than in CC2. Furthermore, expression of proliferation-associated genes, such as CDC45L, CDC20A and KIF20A, in P4 AT-MSCs was higher in CC1 than in CC2, and this difference was also observed in P12 AT-MSCs. These data demonstrated that cell culture density affects the proliferation activity of MSCs, suggesting that it is feasible to design a strategy to prepare suitable MSCs using specific culture conditions. Copyright © 2016 John Wiley & Sons, Ltd.

Effects of Electromagnetic Stimulation on Cell Density and Neural Markers in Murine Enteric Cell Cultures

International Nuclear Information System (INIS)

Carreon-Rodriguez, A.; Belkind-Gerson, J.; Serrano-Luna, G.; Canedo-Dorantes, L.

2008-01-01

Availability of adult stem cells from several organs like bone marrow, umbilical cord blood or peripheral blood has become a powerful therapeutic tool for many chronic diseases. Potential of adult stem cells for regeneration extents to other tissues among them the nervous system. However two obstacles should be resolved before such cells could be currently applied in clinical practice: a) slow growth rate and b) ability to form enough dense colonies in order to populate a specific injury or cellular deficiency. Many approaches have been explored as genetic differentiation programs, growth factors, and supplemented culture media, among others. Electromagnetic field stimulation of differentiation, proliferation, migration, and particularly on neurogenesis is little known. Since the biological effects of ELF-EMF are well documented, we hypothesize ELF-EMF could affect growth and maturation of stem cells derived of enteric tissue

Hyaluronan preserves the proliferation and differentiation potentials of long-term cultured murine adipose-derived stromal cells

International Nuclear Information System (INIS)

Chen, P.-Y.; Huang, Lynn L.H.; Hsieh, H.-J.

2007-01-01

For long-term culture, murine adipose-derived stromal cells (mADSCs) at latter passages demonstrated a marked decline in proliferative activity, exhibited senescent morphology and reduced differentiation potentials, particularly osteogenesis. To extend the lifespan of mADSCs, two culture conditions containing hyaluronan (HA) was compared in our study, one as a culture medium supplement (SHA), and the other where HA was pre-coated on culture surface (CHA). mADSCs cultivated with SHA exhibited a prolonged lifespan, reduced cellular senescence, and enhanced osteogenic potential compared to regular culture condition (control). Upon CHA treatment, mADSCs tended to form cell aggregates with gradual growth profiles, while their differentiation activities remained similar to SHA groups. After transferring mADSCs from CHA to control surface, they were shown to have an extended lifespan and an increase of osteogenic potential. Our results suggested that HA can be useful for preserving the proliferation and differentiation potentials of long-term cultured mADSCs

Recombinant Protein Production and Insect Cell Culture and Process

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Spaulding, Glenn F. (Inventor); Goodwin, Thomas J. (Inventor); OConnor, Kim C. (Inventor); Francis, Karen M. (Inventor); Andrews, Angela D. (Inventor); Prewett, Tracey L. (Inventor)

1997-01-01

A process has been developed for recombinant production of selected polypeptides using transformed insect cells cultured in a horizontally rotating culture vessel modulated to create low shear conditions. A metabolically transformed insect cell line is produced using the culture procedure regardless of genetic transformation. The recombinant polypeptide can be produced by an alternative process using virtually infected or stably transformed insect cells containing a gene encoding the described polypeptide. The insect cells can also be a host for viral production.

Metabolite profiling of microfluidic cell culture conditions for droplet based screening

DEFF Research Database (Denmark)

Björk, Sara M.; Sjoström, Staffan L.; Svahn, Helene Andersson

2015-01-01

We investigate the impact of droplet culture conditions on cell metabolic state by determining key metabolite concentrations in S. cerevisiae cultures in different microfluidic droplet culture formats. Control of culture conditions is critical for single cell/clone screening in droplets......, such as directed evolution of yeast, as cell metabolic state directly affects production yields from cell factories. Here, we analyze glucose, pyruvate, ethanol, and glycerol, central metabolites in yeast glucose dissimilation to establish culture formats for screening of respiring as well as fermenting yeast...... limited cultures, whereas the metabolite profiles of cells cultured in the alternative wide tube droplet incubation format resemble those from aerobic culture. Furthermore, we demonstrate retained droplet stability and size in the new better oxygenated droplet incubation format....

A Cell Culture Approach to Optimized Human Corneal Endothelial Cell Function

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Bartakova, Alena; Kuzmenko, Olga; Alvarez-Delfin, Karen; Kunzevitzky, Noelia J.; Goldberg, Jeffrey L.

2018-01-01

Purpose Cell-based therapies to replace corneal endothelium depend on culture methods to optimize human corneal endothelial cell (HCEC) function and minimize endothelial-mesenchymal transition (EnMT). Here we explore contribution of low-mitogenic media on stabilization of phenotypes in vitro that mimic those of HCECs in vivo. Methods HCECs were isolated from cadaveric donor corneas and expanded in vitro, comparing continuous presence of exogenous growth factors (“proliferative media”) to media without those factors (“stabilizing media”). Identity based on canonical morphology and expression of surface marker CD56, and function based on formation of tight junction barriers measured by trans-endothelial electrical resistance assays (TEER) were assessed. Results Primary HCECs cultured in proliferative media underwent EnMT after three to four passages, becoming increasingly fibroblastic. Stabilizing the cells before each passage by switching them to a media low in mitogenic growth factors and serum preserved canonical morphology and yielded a higher number of cells. HCECs cultured in stabilizing media increased both expression of the identity marker CD56 and also tight junction monolayer integrity compared to cells cultured without stabilization. Conclusions HCECs isolated from donor corneas and expanded in vitro with a low-mitogenic media stabilizing step before each passage demonstrate more canonical structural and functional features and defer EnMT, increasing the number of passages and total canonical cell yield. This approach may facilitate development of HCEC-based cell therapies. PMID:29625488

Blood-Forming Stem Cell Transplants

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... to Ask about Your Treatment Research Blood-Forming Stem Cell Transplants On This Page What are bone marrow ... Considering becoming a bone marrow or a blood stem cell donor? View this video on YouTube. Follow a ...

Sponge cell culture? A molecular identification method for sponge cells

NARCIS (Netherlands)

Sipkema, D.; Heilig, G.H.J.; Akkermans, A.D.L.; Osinga, R.; Tramper, J.; Wijffels, R.H.

2003-01-01

Dissociated sponge cells are easily confused with unicellular organisms. This has been an obstacle in the development of sponge-cell lines. We developed a molecular detection method to identify cells of the sponge Dysidea avara in dissociated cell cultures. The 18S ribosomal RNA gene from a Dysidea

Effect of Dynamic Culture and Periodic Compression on Human Mesenchymal Stem Cell Proliferation and Chondrogenesis.

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Guo, Ting; Yu, Li; Lim, Casey G; Goodley, Addison S; Xiao, Xuan; Placone, Jesse K; Ferlin, Kimberly M; Nguyen, Bao-Ngoc B; Hsieh, Adam H; Fisher, John P

2016-07-01

We have recently developed a bioreactor that can apply both shear and compressive forces to engineered tissues in dynamic culture. In our system, alginate hydrogel beads with encapsulated human mesenchymal stem cells (hMSCs) were cultured under different dynamic conditions while subjected to periodic, compressive force. A customized pressure sensor was developed to track the pressure fluctuations when shear forces and compressive forces were applied. Compared to static culture, dynamic culture can maintain a higher cell population throughout the study. With the application of only shear stress, qRT-PCR and immunohistochemistry revealed that hMSCs experienced less chondrogenic differentiation than the static group. The second study showed that chondrogenic differentiation was enhanced by additional mechanical compression. After 14 days, alcian blue staining showed more extracellular matrix formed in the compression group. The upregulation of the positive chondrogenic markers such as Sox 9, aggrecan, and type II collagen were demonstrated by qPCR. Our bioreactor provides a novel approach to apply mechanical forces to engineered cartilage. Results suggest that a combination of dynamic culture with proper mechanical stimulation may promote efficient progenitor cell expansion in vitro, thereby allowing the culture of clinically relevant articular chondrocytes for the treatment of articular cartilage defects.

Culturing bone marrow cells with dexamethasone and ascorbic acid improves osteogenic cell sheet structure.

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Akahane, M; Shimizu, T; Kira, T; Onishi, T; Uchihara, Y; Imamura, T; Tanaka, Y

2016-11-01

To assess the structure and extracellular matrix molecule expression of osteogenic cell sheets created via culture in medium with both dexamethasone (Dex) and ascorbic acid phosphate (AscP) compared either Dex or AscP alone. Osteogenic cell sheets were prepared by culturing rat bone marrow stromal cells in a minimal essential medium (MEM), MEM with AscP, MEM with Dex, and MEM with Dex and AscP (Dex/AscP). The cell number and messenger (m)RNA expression were assessed in vitro, and the appearance of the cell sheets was observed after mechanical retrieval using a scraper. β-tricalcium phosphate (β-TCP) was then wrapped with the cell sheets from the four different groups and subcutaneously implanted into rats. After mechanical retrieval, the osteogenic cell sheets from the MEM, MEM with AscP, and MEM with Dex groups appeared to be fragmented or incomplete structures. The cell sheets cultured with Dex/AscP remained intact after mechanical retrieval, without any identifiable tears. Culture with Dex/AscP increased the mRNA and protein expression of extracellular matrix proteins and cell number compared with those of the other three groups. More bridging bone formation was observed after transplantation of the β-TCP scaffold wrapped with cell sheets cultured with Dex/AscP, than in the other groups. These results suggest that culture with Dex/AscP improves the mechanical integrity of the osteogenic cell sheets, allowing retrieval of the confluent cells in a single cell sheet structure. This method may be beneficial when applied in cases of difficult tissue reconstruction, such as nonunion, bone defects, and osteonecrosis.Cite this article: M. Akahane, T. Shimizu, T. Kira, T. Onishi, Y. Uchihara, T. Imamura, Y. Tanaka. Culturing bone marrow cells with dexamethasone and ascorbic acid improves osteogenic cell sheet structure. Bone Joint Res 2016;5:569-576. DOI: 10.1302/2046-3758.511.BJR-2016-0013.R1. © 2016 Akahane et al.

Three-dimensional culture and interaction of cancer cells and dendritic cells in an electrospun nano-submicron hybrid fibrous scaffold

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Kim, Tae-Eon; Kim, Chang Gun; Kim, Jin Soo; Jin, Songwan; Yoon, Sik; Bae, Hae-Rahn; Kim, Jeong-Hwa; Jeong, Young Hun; Kwak, Jong-Young

2016-01-01

An artificial three-dimensional (3D) culture system that mimics the tumor microenvironment in vitro is an essential tool for investigating the cross-talk between immune and cancer cells in tumors. In this study, we developed a 3D culture system using an electrospun poly(ε-caprolactone) (PCL) nanofibrous scaffold (NFS). A hybrid NFS containing an uninterrupted network of nano- and submicron-scale fibers (400 nm to 2 µm) was generated by deposition onto a stainless steel mesh instead of an aluminum plate. The hybrid NFS contained multiplanar pores in a 3D structure. Surface-seeded mouse CT26 colon cancer cells and bone marrow-derived dendritic cells (BM-DCs) were able to infiltrate the hybrid NFS within several hours. BM-DCs cultured on PCL nanofibers showed a baseline inactive form, and lipopolysaccharide (LPS)-activated BM-DCs showed increased expression of CD86 and major histocompatibility complex Class II. Actin and phosphorylated FAK were enriched where unstimulated and LPS-stimulated BM-DCs contacted the fibers in the 3D hybrid NFS. When BM-DCs were cocultured with mitoxantrone-treated CT26 cells in a 3D hybrid NFS, BM-DCs sprouted cytoplasm to, migrated to, synapsed with, and engulfed mitoxantrone-treated CT26 cancer cells, which were similar to the naturally occurring cross-talk between these two types of cells. The 3D hybrid NFS developed here provides a 3D structure for coculture of cancer and immune cells. PMID:27042051

21st Century Cell Culture for 21st Century Toxicology.

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Pamies, David; Hartung, Thomas

2017-01-17

There is no good science in bad models. Cell culture is especially prone to artifacts. A number of novel cell culture technologies have become more broadly available in the 21st century, which allow overcoming limitations of traditional culture and are more physiologically relevant. These include the use of stem-cell derived human cells, cocultures of different cell types, scaffolds and extracellular matrices, perfusion platforms (such as microfluidics), 3D culture, organ-on-chip technologies, tissue architecture, and organ functionality. The physiological relevance of such models is further enhanced by the measurement of biomarkers (e.g., key events of pathways), organ specific functionality, and more comprehensive assessment cell responses by high-content methods. These approaches are still rarely combined to create microphysiological systems. The complexity of the combination of these technologies can generate results closer to the in vivo situation but increases the number of parameters to control, bringing some new challenges. In fact, we do not argue that all cell culture needs to be that sophisticated. The efforts taken are determined by the purpose of our experiments and tests. If only a very specific molecular target to cell response is of interest, a very simple model, which reflects this, might be much more suited to allow standardization and high-throughput. However, the less defined the end point of interest and cellular response are, the better we should approximate organ- or tissue-like culture conditions to make physiological responses more probable. Besides these technologic advances, important progress in the quality assurance and reporting on cell cultures as well as the validation of cellular test systems brings the utility of cell cultures to a new level. The advancement and broader implementation of Good Cell Culture Practice (GCCP) is key here. In toxicology, this is a major prerequisite for meaningful and reliable results, ultimately

Microfluidic perfusion culture of human induced pluripotent stem cells under fully defined culture conditions.

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Yoshimitsu, Ryosuke; Hattori, Koji; Sugiura, Shinji; Kondo, Yuki; Yamada, Rotaro; Tachikawa, Saoko; Satoh, Taku; Kurisaki, Akira; Ohnuma, Kiyoshi; Asashima, Makoto; Kanamori, Toshiyuki

2014-05-01

Human induced pluripotent stem cells (hiPSCs) are a promising cell source for drug screening. For this application, self-renewal or differentiation of the cells is required, and undefined factors in the culture conditions are not desirable. Microfluidic perfusion culture allows the production of small volume cultures with precisely controlled microenvironments, and is applicable to high-throughput cellular environment screening. Here, we developed a microfluidic perfusion culture system for hiPSCs that uses a microchamber array chip under defined extracellular matrix (ECM) and culture medium conditions. By screening various ECMs we determined that fibronectin and laminin are appropriate for microfluidic devices made out of the most popular material, polydimethylsiloxane (PDMS). We found that the growth rate of hiPSCs under pressure-driven perfusion culture conditions was higher than under static culture conditions in the microchamber array. We applied our new system to self-renewal and differentiation cultures of hiPSCs, and immunocytochemical analysis showed that the state of the hiPSCs was successfully controlled. The effects of three antitumor drugs on hiPSCs were comparable between microchamber array and 96-well plates. We believe that our system will be a platform technology for future large-scale screening of fully defined conditions for differentiation cultures on integrated microfluidic devices. © 2013 Wiley Periodicals, Inc.

Quantitative volumetric Raman imaging of three dimensional cell cultures

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Kallepitis, Charalambos; Bergholt, Mads S.; Mazo, Manuel M.; Leonardo, Vincent; Skaalure, Stacey C.; Maynard, Stephanie A.; Stevens, Molly M.

2017-03-01

The ability to simultaneously image multiple biomolecules in biologically relevant three-dimensional (3D) cell culture environments would contribute greatly to the understanding of complex cellular mechanisms and cell-material interactions. Here, we present a computational framework for label-free quantitative volumetric Raman imaging (qVRI). We apply qVRI to a selection of biological systems: human pluripotent stem cells with their cardiac derivatives, monocytes and monocyte-derived macrophages in conventional cell culture systems and mesenchymal stem cells inside biomimetic hydrogels that supplied a 3D cell culture environment. We demonstrate visualization and quantification of fine details in cell shape, cytoplasm, nucleus, lipid bodies and cytoskeletal structures in 3D with unprecedented biomolecular specificity for vibrational microspectroscopy.

Xylogenesis in zinnia (Zinnia elegans) cell cultures: unravelling the regulatory steps in a complex developmental programmed cell death event.

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Iakimova, Elena T; Woltering, Ernst J

2017-04-01

Physiological and molecular studies support the view that xylogenesis can largely be determined as a specific form of vacuolar programmed cell death (PCD). The studies in xylogenic zinnia cell culture have led to many breakthroughs in xylogenesis research and provided a background for investigations in other experimental models in vitro and in planta . This review discusses the most essential earlier and recent findings on the regulation of xylem elements differentiation and PCD in zinnia and other xylogenic systems. Xylogenesis (the formation of water conducting vascular tissue) is a paradigm of plant developmental PCD. The xylem vessels are composed of fused tracheary elements (TEs)-dead, hollow cells with patterned lignified secondary cell walls. They result from the differentiation of the procambium and cambium cells and undergo cell death to become functional post-mortem. The TE differentiation proceeds through a well-coordinated sequence of events in which differentiation and the programmed cellular demise are intimately connected. For years a classical experimental model for studies on xylogenesis was the xylogenic zinnia (Zinnia elegans) cell culture derived from leaf mesophyll cells that, upon induction by cytokinin and auxin, transdifferentiate into TEs. This cell system has been proven very efficient for investigations on the regulatory components of xylem differentiation which has led to many discoveries on the mechanisms of xylogenesis. The knowledge gained from this system has potentiated studies in other xylogenic cultures in vitro and in planta. The present review summarises the previous and latest findings on the hormonal and biochemical signalling, metabolic pathways and molecular and gene determinants underlying the regulation of xylem vessels differentiation in zinnia cell culture. Highlighted are breakthroughs achieved through the use of xylogenic systems from other species and newly introduced tools and analytical approaches to study the

The Effect of Primary Cancer Cell Culture Models on the Results of Drug Chemosensitivity Assays: The Application of Perfusion Microbioreactor System as Cell Culture Vessel

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Chen, Yi-Dao; Huang, Shiang-Fu; Wang, Hung-Ming

2015-01-01

To precisely and faithfully perform cell-based drug chemosensitivity assays, a well-defined and biologically relevant culture condition is required. For the former, a perfusion microbioreactor system capable of providing a stable culture condition was adopted. For the latter, however, little is known about the impact of culture models on the physiology and chemosensitivity assay results of primary oral cavity cancer cells. To address the issues, experiments were performed. Results showed that minor environmental pH change could significantly affect the metabolic activity of cells, demonstrating the importance of stable culture condition for such assays. Moreover, the culture models could also significantly influence the metabolic activity and proliferation of cells. Furthermore, the choice of culture models might lead to different outcomes of chemosensitivity assays. Compared with the similar test based on tumor-level assays, the spheroid model could overestimate the drug resistance of cells to cisplatin, whereas the 2D and 3D culture models might overestimate the chemosensitivity of cells to such anticancer drug. In this study, the 3D culture models with same cell density as that in tumor samples showed comparable chemosensitivity assay results as the tumor-level assays. Overall, this study has provided some fundamental information for establishing a precise and faithful drug chemosensitivity assay. PMID:25654105

In vitro formation of the Merkel cell-neurite complex in embryonic mouse whiskers using organotypic co-cultures.

Science.gov (United States)

Ishida, Kentaro; Saito, Tetsuichiro; Mitsui, Toshiyuki

2018-06-01

A Merkel cell-neurite complex is a touch receptor composed of specialized epithelial cells named Merkel cells and peripheral sensory nerves in the skin. Merkel cells are found in touch-sensitive skin components including whisker follicles. The nerve fibers that innervate Merkel cells of a whisker follicle extend from the maxillary branch of the trigeminal ganglion. Whiskers as a sensory organ attribute to the complicated architecture of the Merkel cell-neurite complex, and therefore it is intriguing how the structure is formed. However, observing the dynamic process of the formation of a Merkel cell-neurite complex in whiskers during embryonic development is still difficult. In this study, we tried to develop an organotypic co-culture method of a whisker pad and a trigeminal ganglion explant to form the Merkel cell-neurite complex in vitro. We initially developed two distinct culture methods of a single whisker row and a trigeminal ganglion explant, and then combined them. By dissecting and cultivating a single row from a whisker pad, the morphogenesis of whisker follicles could be observed under a microscope. After the co-cultivation of the whisker row with a trigeminal ganglion explant, a Merkel cell-neurite complex composed of Merkel cells, which were positive for both cytokeratin 8 and SOX2, Neurofilament-H-positive trigeminal nerve fibers and Schwann cells expressing Nestin, SOX2 and SOX10 was observed via immunohistochemical analyses. These results suggest that the process for the formation of a Merkel cell-neurite complex can be observed under a microscope using our organotypic co-culture method. © 2018 Japanese Society of Developmental Biologists.

Bags versus flasks: a comparison of cell culture systems for the production of dendritic cell-based immunotherapies.

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Fekete, Natalie; Béland, Ariane V; Campbell, Katie; Clark, Sarah L; Hoesli, Corinne A

2018-04-19

In recent years, cell-based therapies targeting the immune system have emerged as promising strategies for cancer treatment. This review summarizes manufacturing challenges related to production of antigen presenting cells as a patient-tailored cancer therapy. Understanding cell-material interactions is essential because in vitro cell culture manipulations to obtain mature antigen-producing cells can significantly alter their in vivo performance. Traditional antigen-producing cell culture protocols often rely on cell adhesion to surface-treated hydrophilic polystyrene flasks. More recent commercial and investigational cancer immunotherapy products were manufactured using suspension cell culture in closed hydrophobic fluoropolymer bags. The shift to closed cell culture systems can decrease risks of contamination by individual operators, as well as facilitate scale-up and automation. Selecting closed cell culture bags over traditional open culture systems entails different handling procedures and processing controls, which can affect product quality. Changes in culture vessels also entail changes in vessel materials and geometry, which may alter the cell microenvironment and resulting cell fate decisions. Strategically designed culture systems will pave the way for the generation of more sophisticated and highly potent cell-based cancer vaccines. As an increasing number of cell-based therapies enter the clinic, the selection of appropriate cell culture vessels and materials becomes a critical consideration that can impact the therapeutic efficacy of the product, and hence clinical outcomes and patient quality of life. © 2018 The Authors Transfusion published by Wiley Periodicals, Inc. on behalf of AABB.