Simplified non-cultured non-trypsinised epidermal cell graft technique followed by psoralen and ultraviolet a light therapy for stable vitiligo

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Dilip Kachhawa

2017-01-01

Full Text Available Background and Aims: Stable vitiligo can be treated by various surgical procedures. Non-cultured melanocyte grafting techniques were developed to overcome the time-consuming process of culture while at the same time providing acceptable results. All the techniques using non-cultured melanocyte transfer involve trypsinisation as an integral step. Jodhpur technique used by the author is autologous, non-cultured, non-trypsinised, epidermal cell grafting. Settings and Design: The study was conducted on patients visiting the dermatology outpatient department of a tertiary health centre in Western Rajasthan. Materials and Methods: At the donor site, mupirocin ointment was applied and dermabrasion was done with the help of micromotor dermabrader till pinpoint bleeding was seen. The paste-like material obtained by this procedure containing melanocytes and keratinocytes admixed with the ointment base was harvested with spatula and was subsequently spread over the recipient area. Recipient site was prepared in the same manner by dermabrasion. After 10 days, dressing at both sites was removed taking utmost care at the recipient site as there was a theoretical risk of dislodging epidermal cells. Results: In a study of 437 vitiligo patches, more than 75% re-pigmentation (excellent improvement was seen in 41% of the patches. Lesions on thigh (100%, face (75% and trunk (50% showed maximal excellent improvement, whereas patches on joints and acral areas did not show much improvement. Conclusions: This technique is a simplified, cost effective, less time-consuming alternative to other techniques which involve tryspsinisation of melanocytes and at the same time provides satisfactory uniform pigmentation.

Microfluidic cell culture systems for drug research.

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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.

Drifter technique: a new method to obtain metaphases in Hep-2 cell line cultures

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Eleonidas Moura Lima

2005-07-01

Full Text Available The Hep-2 cell line is derived from laryngeal carcinoma cells and is often utilized as a model in carcinogenesis and mutagenesis tests. To evaluate the proliferative potential of this line, we developed a cytogenetic methodology (drifter technique to obtain metaphases from cells that loose cellular adhesion when they underwent mitosis in culture. By this procedure, 2000 cells were counted, resulting in a mitotic index (MI of 22.2%. Although this MI was not statistically different from the one obtained using either a classical cytogenetic method or a cell synchronization technique, the drifter technique has the advantage of not requiring the use of some reagents for the obtention of metaphases and also of diminishing the consumption of maintenance reagents for this cell line.A linhagem celular Hep-2 é formada por células de carcinoma da laringe e é muito utilizada em modelos de carcinogênese e mutagenêse. Para avaliar o potencial proliferativo desta linhagem, desenvolvemos uma metodologia citogenética (técnica do sobrenadante para obtenção de metáfases a partir de células que, ao entrarem em mitose, perdem adesão celular, ficando em suspensão no meio de cultura. Através deste procedimento, foram contadas 2000 células, correspondendo a um índice mitótico (IM de 22.2% . Apesar de o IM obtido por esta técnica não ter sido estatisticamente diferente do IM obtido por outras metodologias citogenéticas clássicas, a técnica do sobrenadante é vantajosa porque elimina o uso de alguns reagentes utilizados na obtenção de metáfases e também diminui o consumo de reagentes de manutenção desta linhagem.

A double labeling technique for performing immunocytochemistry and in situ hybridization in virus infected cell cultures and tissues

International Nuclear Information System (INIS)

Gendelman, H.E.; Moench, T.R.; Narayan, O.; Griffin, D.E.; Clements, J.E.

1985-01-01

This report describes a combined immunocytochemical and in situ hybridization procedure which allows visualization of cellular or viral antigens and viral RNA in the same cell. Cultures infected with visna or measles virus were fixed in periodate-lysine-paraformaldehyde-glutaraldehyde, stained by the avidin-biotin-peroxidase technique using antibodies to viral or cellular proteins and then incubated with radiolabeled specific DNA probes (in situ hybridization). This technique provides a new approach to the study of viral pathogenesis by: (1) identifying the types of cells which are infected in the host and (2) identifying points of blockade in the virus life cycle during persistent infections. (Auth.)

Biogelx: Cell Culture on Self-Assembling Peptide Gels.

Science.gov (United States)

Harper, Mhairi M; Connolly, Michael L; Goldie, Laura; Irvine, Eleanore J; Shaw, Joshua E; Jayawarna, Vineetha; Richardson, Stephen M; Dalby, Matthew J; Lightbody, David; Ulijn, Rein V

2018-01-01

Aromatic peptide amphiphiles can form self-supporting nanostructured hydrogels with tunable mechanical properties and chemical compositions. These hydrogels are increasingly applied in two-dimensional (2D) and three-dimensional (3D) cell culture, where there is a rapidly growing need to store, grow, proliferate, and manipulate naturally derived cells within a hydrated, 3D matrix. Biogelx Limited is a biomaterials company, created to commercialize these bio-inspired hydrogels to cell biologists for a range of cell culture applications. This chapter describes methods of various characterization and cell culture techniques specifically optimized for compatibility with Biogelx products.

Tissue culture as a plant production technique for horticultural crops

African Journals Online (AJOL)

STORAGESEVER

2009-08-18

Aug 18, 2009 ... Recovery of regenerants from transformed cells. - Cell culture .... methods. Micropropagation techniques. Micropropagation is a simple concept. The basic pro- tocols were well established by the 1960s and a whole research field and ... the environment are naturally contaminated on their sur- faces (and ...

3D Cell Culture in Alginate Hydrogels

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Therese Andersen

2015-03-01

Full Text Available This review compiles information regarding the use of alginate, and in particular alginate hydrogels, in culturing cells in 3D. Knowledge of alginate chemical structure and functionality are shown to be important parameters in design of alginate-based matrices for cell culture. Gel elasticity as well as hydrogel stability can be impacted by the type of alginate used, its concentration, the choice of gelation technique (ionic or covalent, and divalent cation chosen as the gel inducing ion. The use of peptide-coupled alginate can control cell–matrix interactions. Gelation of alginate with concomitant immobilization of cells can take various forms. Droplets or beads have been utilized since the 1980s for immobilizing cells. Newer matrices such as macroporous scaffolds are now entering the 3D cell culture product market. Finally, delayed gelling, injectable, alginate systems show utility in the translation of in vitro cell culture to in vivo tissue engineering applications. Alginate has a history and a future in 3D cell culture. Historically, cells were encapsulated in alginate droplets cross-linked with calcium for the development of artificial organs. Now, several commercial products based on alginate are being used as 3D cell culture systems that also demonstrate the possibility of replacing or regenerating tissue.

Contributions of 3D Cell Cultures for Cancer Research.

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Ravi, Maddaly; Ramesh, Aarthi; Pattabhi, Aishwarya

2017-10-01

Cancer cell lines have contributed immensely in understanding the complex physiology of cancers. They are excellent material for studies as they offer homogenous samples without individual variations and can be utilised with ease and flexibility. Also, the number of assays and end-points one can study is almost limitless; with the advantage of improvising, modifying or altering several variables and methods. Literally, a new dimension to cancer research has been achieved by the advent of 3Dimensional (3D) cell culture techniques. This approach increased many folds the ways in which cancer cell lines can be utilised for understanding complex cancer biology. 3D cell culture techniques are now the preferred way of using cancer cell lines to bridge the gap between the 'absolute in vitro' and 'true in vivo'. The aspects of cancer biology that 3D cell culture systems have contributed include morphology, microenvironment, gene and protein expression, invasion/migration/metastasis, angiogenesis, tumour metabolism and drug discovery, testing chemotherapeutic agents, adaptive responses and cancer stem cells. We present here, a comprehensive review on the applications of 3D cell culture systems for these aspects of cancers. J. Cell. Physiol. 232: 2679-2697, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Application of hanging drop technique for stem cell differentiation and cytotoxicity studies.

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Banerjee, Meenal; Bhonde, Ramesh R

2006-05-01

The aim of our study is to explore the possibility of using an ancient method of culture technique- the hanging drop technique for stem cell differentiation and cytotoxicity testing. We demonstrate here a variety of novel applications of this age old technique not only to harness the differentiation potential of stem cells into specific lineages but also for cytotoxicity studies. Here we have prepared hanging drop cultures by placing 20 microl micro-drops of nutrient media and 10% Fetal Calf Serum (FCS) containing cells of interest on the lids of 60 mm dishes. Bottom plates of the dishes were filled with sterile Phosphate Buffer Saline (PBS) to avoid desiccation of samples. Lids were then placed on the bottom plates to achieve hanging drop cultures. We utilized this technique for cultivation of ciliated epithelia to study cytotoxicity and differentiation of bone marrow stromal cells. Most importantly the modified culture technique presented here is simple, economical and cost effective in terms of the time taken and the reagents required and are amenable to goal specific modification such as cytotoxicity testing. It is advantageous over the existing system in terms of retention of viability and functionality for longer duration and for providing three dimensional growth micro-environment making it useful for organotypic cultures and in vivo simulation.

Improvement of large quantity breeding method for making radiation breeding efficient and development of cell culture techniques, (3)

International Nuclear Information System (INIS)

Hogetsu, Daisuke; Koyama, Motoko; Minami, Harufumi

1990-01-01

In the creation of useful mutant plants using cell culture techniques, the examination on the effectiveness of selecting useful mutation at cell level and the possibility of raising the selection efficiency by irradiation was aimed at. The experimental method is described. The young plants which accumulate proline were obtained. The cells which showed the resistance to hydroxyproline also showed the resistance to salt. In the improvement of redifferentiation ability by irradiation, the method of fixing IAA in the tissues of azuki plants was examined. The possibility of examining the change of IAA due to irradiation by microautoradiography was obtained. It is intended to examine the distribution of IAA in the formation of adventitious roots from the epicotyl of azuki plants. In the introduction of cell engineering techniques in radiation breeding, it is the objective to introduce the genes which resist sour rot that Brassica campestris, Brassica napus, Brassica oleracea and so on have by utilizing cell fusion process. The fusion of the reproduction cells of Brassica napus pollens and the cell protoplasts of Brassica campestris was successfully carried out. The possibility of new asymmetric fusion in Brassica napus was shown. (K.I.)

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.

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

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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.

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

Expression of human immunodeficiency virus (HIV) in naturally infected peripheral blood mononuclear cells: comparison of a standard co-culture technique with a newly developed microculture method.

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Eberlein, B; Baur, A; Neundorfer, M; Jahn, G

1991-05-01

Peripheral blood mononuclear cells (PBMCs) from 29 patients infected with human immunodeficiency virus (HIV) were cultured by two different methods. One was the standard co-culture technique, the other a newly developed microculture method. In this assay 10(6) PBMCs were cultivated in 250 microliters medium, no activating agents or allogeneic cells were present. P24 antigen production measured by this method was found in 7 out of 11 PBMC cultures of patients in the Walter Reed (WR) stage 1 or 2, whereas only 4 samples were positive by the co-culture procedure. Cultures from patients in the later stages of the disease (WR 5/6) showed a higher p24 production by the co-culture method than by the microculture assay. It is assumed that rapidly growing HIV strains can be better assessed by the co-culture method which may select for these strains. P24 expression can be more easily obtained by the microculture technique even in cases where slowly replicating strains may be present. In conclusion, results from the microculture procedure described may be a useful supplementation to findings observed by the co-culture method.

Laser-based direct-write techniques for cell printing

Energy Technology Data Exchange (ETDEWEB)

Schiele, Nathan R; Corr, David T [Biomedical Engineering Department, Rensselaer Polytechnic Institute, Troy, NY (United States); Huang Yong [Department of Mechanical Engineering, Clemson University, Clemson, SC (United States); Raof, Nurazhani Abdul; Xie Yubing [College of Nanoscale Science and Engineering, University at Albany, SUNY, Albany, NY (United States); Chrisey, Douglas B, E-mail: schien@rpi.ed, E-mail: chrisd@rpi.ed [Material Science and Engineering Department, Rensselaer Polytechnic Institute, Troy, NY (United States)

2010-09-15

Fabrication of cellular constructs with spatial control of cell location ({+-}5 {mu}m) is essential to the advancement of a wide range of applications including tissue engineering, stem cell and cancer research. Precise cell placement, especially of multiple cell types in co- or multi-cultures and in three dimensions, can enable research possibilities otherwise impossible, such as the cell-by-cell assembly of complex cellular constructs. Laser-based direct writing, a printing technique first utilized in electronics applications, has been adapted to transfer living cells and other biological materials (e.g., enzymes, proteins and bioceramics). Many different cell types have been printed using laser-based direct writing, and this technique offers significant improvements when compared to conventional cell patterning techniques. The predominance of work to date has not been in application of the technique, but rather focused on demonstrating the ability of direct writing to pattern living cells, in a spatially precise manner, while maintaining cellular viability. This paper reviews laser-based additive direct-write techniques for cell printing, and the various cell types successfully laser direct-written that have applications in tissue engineering, stem cell and cancer research are highlighted. A particular focus is paid to process dynamics modeling and process-induced cell injury during laser-based cell direct writing. (topical review)

Laser-based direct-write techniques for cell printing

International Nuclear Information System (INIS)

Schiele, Nathan R; Corr, David T; Huang Yong; Raof, Nurazhani Abdul; Xie Yubing; Chrisey, Douglas B

2010-01-01

Fabrication of cellular constructs with spatial control of cell location (±5 μm) is essential to the advancement of a wide range of applications including tissue engineering, stem cell and cancer research. Precise cell placement, especially of multiple cell types in co- or multi-cultures and in three dimensions, can enable research possibilities otherwise impossible, such as the cell-by-cell assembly of complex cellular constructs. Laser-based direct writing, a printing technique first utilized in electronics applications, has been adapted to transfer living cells and other biological materials (e.g., enzymes, proteins and bioceramics). Many different cell types have been printed using laser-based direct writing, and this technique offers significant improvements when compared to conventional cell patterning techniques. The predominance of work to date has not been in application of the technique, but rather focused on demonstrating the ability of direct writing to pattern living cells, in a spatially precise manner, while maintaining cellular viability. This paper reviews laser-based additive direct-write techniques for cell printing, and the various cell types successfully laser direct-written that have applications in tissue engineering, stem cell and cancer research are highlighted. A particular focus is paid to process dynamics modeling and process-induced cell injury during laser-based cell direct writing. (topical review)

Response of cultured normal human mammary epithelial cells to X rays

International Nuclear Information System (INIS)

Yang, T.C.; Stampfer, M.R.; Smith, H.S.

1983-01-01

The effect of X rays on the reproductive death of cultured normal human mammary epithelial cells was examined. Techniques were developed for isolating and culturing normal human mammary epithelial cells which provide sufficient cells at second passage for radiation studies, and an efficient clonogenic assay suitable for measuring radiation survival curves. It was found that the survival curves for epithelial cells from normal breast tissue were exponential and had D 0 values of about 109-148 rad for 225 kVp X rays. No consistent change in cell radiosensitivity with the age of donor was observed, and no sublethal damage repair in these cells could be detected with the split-dose technique

Multizone Paper Platform for 3D Cell Cultures

Science.gov (United States)

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

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.

Surface modified alginate microcapsules for 3D cell culture

Science.gov (United States)

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.

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

Ex Vivo Produced Oral Mucosa Equivalent by Using the Direct Explant Cell Culture Technique

Directory of Open Access Journals (Sweden)

Kamile Öztürk

2012-09-01

Full Text Available Objective: The aim of this study is the histological and immunohistochemical evaluation of ex vivo produced oral mucosal equivalents using keratinocytes cultured by direct explant technique.Material and Methods: Oral mucosa tissue samples were obtained from the keratinized gingival tissues of 14 healthy human subjects. Human oral mucosa keratinocytes from an oral mucosa biopsy specimen were dissociated by the explant technique. Once a sufficient population of keratinocytes was reached, they were seeded onto the type IV collagen coated “AlloDerm” and taken for histological and immunohistochemical examinations at 11 days postseeding of the keratinocytes on the cadaveric human dermal matrix.Results: Histopathologically and immunohistochemically, 12 out of 14 successful ex vivo produced oral mucosa equivalents (EVPOME that consisted of a stratified epidermis on a dermal matrix have been developed with keratinocytes cultured by the explant technique.Conclusion: The technical handling involved in the direct explant method at the beginning of the process has fewer steps than the enzymatic method and use of the direct explant technique protocol for culturing of human oral mucosa keratinocyte may be more adequate for EVPOME production.

Ex vivo hyperpolarized MR spectroscopy on isolated renal tubular cells: A novel technique for cell energy phenotyping.

Science.gov (United States)

Juul, Troels; Palm, Fredrik; Nielsen, Per Mose; Bertelsen, Lotte Bonde; Laustsen, Christoffer

2017-08-01

It has been demonstrated that hyperpolarized 13 C MR is a useful tool to study cultured cells. However, cells in culture can alter phenotype, which raises concerns regarding the in vivo significance of such findings. Here we investigate if metabolic phenotyping using hyperpolarized 13 C MR is suitable for cells isolated from kidney tissue, without prior cell culture. Isolation of tubular cells from freshly excised kidney tissue and treatment with either ouabain or antimycin A was investigated with hyperpolarized MR spectroscopy on a 9.4 Tesla preclinical imaging system. Isolation of tubular cells from less than 2 g of kidney tissue generally resulted in more than 10 million live tubular cells. This amount of cells was enough to yield robust signals from the conversion of 13 C-pyruvate to lactate, bicarbonate and alanine, demonstrating that metabolic flux by means of both anaerobic and aerobic pathways can be quantified using this technique. Ex vivo metabolic phenotyping using hyperpolarized 13 C MR in a preclinical system is a useful technique to study energy metabolism in freshly isolated renal tubular cells. This technique has the potential to advance our understanding of both normal cell physiology as well as pathological processes contributing to kidney disease. Magn Reson Med 78:457-461, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

Spatial and temporal single-cell volume estimation by a fluorescence imaging technique with application to astrocytes in primary culture

Science.gov (United States)

Khatibi, Siamak; Allansson, Louise; Gustavsson, Tomas; Blomstrand, Fredrik; Hansson, Elisabeth; Olsson, Torsten

1999-05-01

Cell volume changes are often associated with important physiological and pathological processes in the cell. These changes may be the means by which the cell interacts with its surrounding. Astroglial cells change their volume and shape under several circumstances that affect the central nervous system. Following an incidence of brain damage, such as a stroke or a traumatic brain injury, one of the first events seen is swelling of the astroglial cells. In order to study this and other similar phenomena, it is desirable to develop technical instrumentation and analysis methods capable of detecting and characterizing dynamic cell shape changes in a quantitative and robust way. We have developed a technique to monitor and to quantify the spatial and temporal volume changes in a single cell in primary culture. The technique is based on two- and three-dimensional fluorescence imaging. The temporal information is obtained from a sequence of microscope images, which are analyzed in real time. The spatial data is collected in a sequence of images from the microscope, which is automatically focused up and down through the specimen. The analysis of spatial data is performed off-line and consists of photobleaching compensation, focus restoration, filtering, segmentation and spatial volume estimation.

Production of betalaines by Myrtillocactus cell cultures. Passage from heterotrophic state to autotrophic state with Asparagus cell cultures

Energy Technology Data Exchange (ETDEWEB)

Bulard, C; Mary, J; Chaumont, D; Gudin, C

1982-11-01

Myrtillocactus tissue cultures are grown from the epicotyl of young plantlets. With an appropriate growing medium it is possible, after transfer of fragments of these cultures to a liquid environment, to obtain dissociation and proliferation of cells. The production of betalaic pigments is induced in solid surroundings by adjustement of the growing medium composition and can be maintained in a liquid environment. The multiplication of pigmented cells in suspension may thus be obtained. The conversion of Asparagus cell suspensions from the heterotrophic state (use of lactose as source of carbon) to the autotrophic state (carbon supplied by CO/sub 2/) is obtained by a gradual reduction in the sugar concentration of the medium combined with a rise in the CO/sub 2/ content of the gas mixture atmosphere injected into the cultivator. The passage to the autotrophic state of a Myrtillocactus suspension would enable the production conditions of a metabolite (Betalaine) to be studied by micro-algae culture techniques.

Multiweek Cell Culture Project for Use in Upper-Level Biology Laboratories

Science.gov (United States)

Marion, Rebecca E.; Gardner, Grant E.; Parks, Lisa D.

2012-01-01

This article describes a laboratory protocol for a multiweek project piloted in a new upper-level biology laboratory (BIO 426) using cell culture techniques. Human embryonic kidney-293 cells were used, and several culture media and supplements were identified for students to design their own experiments. Treatments included amino acids, EGF,…

Advanced three-dimensional culture of equine intestinal epithelial stem cells.

Science.gov (United States)

Stewart, A Stieler; Freund, J M; Gonzalez, L M

2018-03-01

Intestinal epithelial stem cells are critical to epithelial repair following gastrointestinal injury. The culture of intestinal stem cells has quickly become a cornerstone of a vast number of new research endeavours that range from determining tissue viability to testing drug efficacy for humans. This study aims to describe the methods of equine stem cell culture and highlights the future benefits of these techniques for the advancement of equine medicine. To describe the isolation and culture of small intestinal stem cells into three-dimensional (3D) enteroids in horses without clinical gastrointestinal abnormalities. Descriptive study. Intestinal samples were collected by sharp dissection immediately after euthanasia. Intestinal crypts containing intestinal stem cells were dissociated from the underlying tissue layers, plated in a 3D matrix and supplemented with growth factors. After several days, resultant 3D enteroids were prepared for immunofluorescent imaging and polymerase chain reaction (PCR) analysis to detect and characterise specific cell types present. Intestinal crypts were cryopreserved immediately following collection and viability assessed. Intestinal crypts were successfully cultured and matured into 3D enteroids containing a lumen and budding structures. Immunofluorescence and PCR were used to confirm the existence of stem cells and all post mitotic, mature cell types, described to exist in the horse intestinal epithelium. Previously frozen crypts were successfully cultured following a freeze-thaw cycle. Tissues were all derived from normal horses. Application of this technique for the study of specific disease was not performed at this time. The successful culture of equine intestinal crypts into 3D "mini-guts" allows for in vitro studies of the equine intestine. Additionally, these results have relevance to future development of novel therapies that harness the regenerative potential of equine intestine in horses with gastrointestinal disease

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.

Endothelial cell cultures as a tool in biomaterial research

NARCIS (Netherlands)

Kirkpatrick, CJ; Otto, M; van Kooten, T; Krump, [No Value; Kriegsmann, J; Bittinger, F

1999-01-01

Progress in biocompatibility and tissue engineering would today be inconceivable without the aid of in vitro techniques. Endothelial cell cultures represent a valuable tool not just in haemocompatibility testing, but also in the concept of designing hybrid organs. In the past endothelial cells (EC)

Is cell culture a risky business? Risk analysis based on scientist survey data.

Science.gov (United States)

Shannon, Mark; Capes-Davis, Amanda; Eggington, Elaine; Georghiou, Ronnie; Huschtscha, Lily I; Moy, Elsa; Power, Melinda; Reddel, Roger R; Arthur, Jonathan W

2016-02-01

Cell culture is a technique that requires vigilance from the researcher. Common cell culture problems, including contamination with microorganisms or cells from other cultures, can place the reliability and reproducibility of cell culture work at risk. Here we use survey data, contributed by research scientists based in Australia and New Zealand, to assess common cell culture risks and how these risks are managed in practice. Respondents show that sharing of cell lines between laboratories continues to be widespread. Arrangements for mycoplasma and authentication testing are increasingly in place, although scientists are often uncertain how to perform authentication testing. Additional risks are identified for preparation of frozen stocks, storage and shipping. © 2015 UICC.

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.

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.

Reduction of fatal graft-versus-host disease by 3H--thymidine suicide of donor cells cultured with host cells

International Nuclear Information System (INIS)

Cheever, M.A.; Einstein, A.B. Jr.; Kempf, R.A.; Fefer, A.

1977-01-01

The effect of the tritiated thymidine ( 3 H-TdR) suicide technique on the ability of donor cells to induce fatal graft-versus-host disease (GVHD) was studied. C57BL/6 (H-2/sup b/) spleen cells were stimulated in vitro with irradiated BALB/c (H-2/sup d/) Moloney lymphoma cells in mixed culture and 3 H-TdR of high-specific activity added to eliminate proliferating cells. The ability of such cells to induce fatal GVHD was assayed by injecting them i.v. into adult BALB/c mice immunosuppressed with cyclophosphamide (180 mg/kg). These cells induced fatal GVHD in fewer mice (52 percent) than did C57BL/6 cells cultured with BALB/c lymphoma cells but without 3 H-TdR (87 percent) and C57BL/6 cells cultured with irradiated C57BL/6 cells with (95 percent) or without 3 H-TdR (86 percent). Thus, the 3 H-TdR suicide technique greatly diminished the ability of cells to induce lethal GVHD

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

Science.gov (United States)

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.

Plant cell tissue culture: A potential source of chemicals

Energy Technology Data Exchange (ETDEWEB)

Scott, C.D.; Dougall, D.K.

1987-08-01

Higher plants produce many industrially important products. Among these are drugs and medicinal chemicals, essential oils and flavors, vegetable oils and fats, fine and specialty chemicals, and even some commodity chemicals. Although, currently, whole-plant extraction is the primary means of harvesting these materials, the advent of plant cell tissue culture could be a much more effective method of producing many types of phytochemicals. The use of immobilized plant cells in an advanced bioreactor configuration with excretion of the product into the reactor medium may represent the most straightforward way of commercializing such techniques for lower-value chemicals. Important research and development opportunities in this area include screening for plant cultures for nonmedical, lower-value chemicals; understanding and controlling plant cell physiology and biochemistry; optimizing effective immobilization methods; developing more efficient bioreactor concepts; and perfecting product extraction and purification techniques. 62 refs., 2 figs.

Preparation of anti-inflammatory mesenchymal stem/precursor cells (MSCs) through sphere formation using hanging-drop culture technique.

Science.gov (United States)

Bartosh, Thomas J; Ylostalo, Joni H

2014-02-06

Herein, we describe a protocol for preparation of pre-activated anti-inflammatory human mesenchymal stem/precursor cells (MSCs) in 3-D culture without addition of exogenous chemicals or gene-transfer approaches. MSCs are an easily procurable source of multipotent adult stem cells with therapeutic potential largely attributed to their paracrine regulation of inflammation and immunity. However, the culture conditions to prepare the ideal MSCs for cell therapy remain elusive. Furthermore, the reported lag time for activation in experimental models has prompted investigations on pre-activating the cells prior to their administration. In this protocol, standard 2-D culture-expanded MSCs are activated by aggregation into 3-D spheres using hanging-drop cultures. MSC activation is evaluated by real-time PCR and/or ELISA for anti-inflammatory factors (TSG-6, STC-1, PGE2), and by a functional assay using lipopolysaccharide-stimulated macrophage cultures. Further, we elucidate methods to prepare MSC-sphere conditioned medium, intact spheres, and suspension of single cells from spheres for experimental and clinical applications. Copyright © 2014 John Wiley & Sons, Inc.

Preparation of anti-inflammatory mesenchymal stem/precursor cells (MSCs) through sphere formation using hanging drop culture technique

Science.gov (United States)

Bartosh, Thomas J.

2014-01-01

Herein, we describe a protocol for preparation of pre-activated anti-inflammatory human mesenchymal stem/precursor cells (MSCs) in 3D culture without addition of exogenous chemicals or gene transfer approaches. MSCs are an easily procurable source of multipotent adult stem cells with therapeutic potential largely attributed to their paracrine regulation of inflammation and immunity. However, the culture conditions to prepare the ideal MSCs for cell therapy remain elusive. Furthermore, reported lag time for activation in experimental models have prompted investigations to pre-activate the cells prior to their administration. In this protocol, standard 2D culture expanded MSCs are activated by aggregation into 3D spheres using hanging drop cultures. MSC activation is evaluated by real-time PCR and/or ELISA for anti-inflammatory factors (TSG-6, STC-1, PGE2), and by a functional assay using lipopolysaccharide-stimulated macrophage cultures. Furthermore, we elucidate methods to prepare MSC sphere conditioned medium, intact spheres, and suspension of single cells from spheres for experimental and clinical applications. PMID:24510769

Simulation of limiting dilution technique in determination of immunocompetent cells frequency in irradiated cell cultures

International Nuclear Information System (INIS)

Martini Filho, R.J.; Barlette, V.E.; Goes, E.G.; Covas, D.T.; Orellana, M.

2001-01-01

Limiting dilution techniques (LDA) dose-response data have been used to detect immunocompetent T-Cells in microcultures. In this work, LDA frequencies estimates was obtained using χ2 minimization for irradiated cells in a range of 500 to 1,500 cGy. (author)

Experimental Methodology used by Cell Cultures Laboratory from INRMFB to assess the therapeutic effect of natural factors

Directory of Open Access Journals (Sweden)

Munteanu Constantin

2010-11-01

Full Text Available The experimental study design on cell cultures allows the direct biological evaluation at the cellular level, of the therapeutic effect that natural factors can play over the organism.Techniques for obtaining cell cultures requires a complex and laborious task that starts from live tissue sampling, continuous with isolation of cells and their preparation for sowing a culture plate. This preparation involves mechanical and enzymatic action from the researcher on biological material. Derived cell cultures are monitored morphologically by high-performance inverted biological microscope, with video camera for image acquisition. In the final stage, the cells are scraped, and through biochemical and molecular techniques, the therapeutic efficiency hypothesis of the investigated natural factor is verified experimentally. The cell cultures can be crioconservated in special containers with liquid nitrogen.

Establishment of primary bovine intestinal epithelial cell culture and clone method.

Science.gov (United States)

Zhan, Kang; Lin, Miao; Liu, Ming-Mei; Sui, Yang-Nan; Zhao, Guo-Qi

2017-01-01

The aim of this study was to establish bovine intestinal epithelial cell (BIEC) line and provide a novel clone cell method. Although various strategies of bovine cell culture and clone techniques have been reported, these methods remain not established. Here, we culture successfully primary BIECs and establish a novel clone cell method. Our result showed that BIECs could be successfully cultured and passaged about generation 5. These cellular aggregates and clusters were adherent loosely at day 2 of culture. Cell aggregates and clusters start to proliferate after approximately 4 d. The BIECs showed positive reaction against cytokeratin 18, E-cadherin, and characteristics of epithelial-like morphology. In addition, the fatty acid-binding proteins (FABPs), villin, and intestinal peptidase (IP) band were positive in BIECs. Our results suggest that the establishment of culturing and clone BIEC methods will apply to isolate and clone other primary cells. These BIECs could therefore contribute to the study of bovine intestinal nutrient absorption and regulation, immune regulation, and the pathogenesis of the bovine intestinal disease, which will provide intestinal cell model in vitro.

The r.b.e. of different-energy neutrons as determined by human bone-marrow cell-culture techniques

International Nuclear Information System (INIS)

Boeyum, A.; Carsten, A.L.; Chikkappa, G.; Cook, L.; Bullis, J.; Honikel, L.; Cronkite, E.P.

1978-01-01

The effect of X-rays and different-energy neutrons on human bone-marrow cells was studied using two different cell-culture techniques - diffusion chamber (DC) growth and colony formation in vitro (CFU-C). Based on the survival and proliferative granulocytes in DC on day 13, the D 0 value was 80 rad with X-rays, and 117 rad as measured by the CFU-C assay. The D 0 values for neutrons depended on the radiation source and the energy level. The r.b.e. values, which dropped with increasing energy levels of mono-energetic neutrons, were (i) 0.44 MeV; DC 3.7, CFU-C 4.1; (ii) 6 MeV; DC 1.8, CFU-C 2.0; (iii) 15 MeV; DC 1.6, CFU-C 1.6; (iv) fission neutrons; DC 2.6, CFU-C 2.4. (author)

Immunocytochemical characterization of primary cell culture in canine transmissible venereal tumor

Directory of Open Access Journals (Sweden)

Luis M.M. Flórez

Full Text Available Abstract: Immunochemistry with anti-vimentin, anti-lysozyme, anti-alpha 1 antitrypsin, anti-CD3 and anti-CD79α antibodies has been used for characterization of primary cell culture in the transmissible venereal tumor (TVT. Samples for primary cell culture and immunohistochemistry assays were taken from eight dogs with cytological and clinical diagnosis of TVT. To validate the immunochemical results in the primary cell culture of TVT, a chromosome count was performed. For the statistical analysis, the Mann-Whitney test with p<0.05 was used. TVT tissues and culture cells showed intense anti-vimentin immunoreactivity, lightly to moderate immunoreactivity for anti-lysozyme, and mild for anti-alpha-antitrypsin. No marking was achieved for CD3 and CD79α. All culture cells showed chromosomes variable number of 56 to 68. This is the first report on the use of immunocytochemical characterization in cell culture of TVT. Significant statistic difference between immunochemistry in tissue and culture cell was not established, what suggests that the use of this technique may provide greater certainty for the confirmation of tumors in the primary culture. This fact is particularly important because in vitro culture of tumor tissues has been increasingly used to provide quick access to drug efficacy and presents relevant information to identify potential response to anticancer medicine; so it is possible to understand the behavior of the tumor.

Radiation transformation in differentiated human cells in culture

International Nuclear Information System (INIS)

Mothersill, C.; Seymour, C.; Moriarty, M.; Malone, J.; Byrne, P.; Hennessy, T.

1986-01-01

A tissue culture technique is described for human thyroid tissue as an approach to studying mechanisms of human radiation carcinogenesis. Normal human tissue obtained from surgery is treated in one of two ways, depending upon size of specimen. Large pieces are completely digested in trypsin/ collagenase solution to a single cell suspension. Small pieces of tissue are plated as explants following partial digestion in trypsin/collagenase solution. Following irradiation of the primary differentiated monolayers (normally 10 days after plating), the development of transformed characteristics is monitored in the subsequent subcultures. A very high level of morphological and functional differentiation is apparent in the primary cultures. Over a period of approx. 6 months, the irradiated surviving cells continue to grow in culture, unlike the unirradiated controls which senesce after 2-3 subcultures. (UK)

A co-cultured skin model based on cell support membranes

International Nuclear Information System (INIS)

Dai, N.-T.; Yeh, M.-K.; Liu, Demeral David; Adams, E.F.; Chiang, C.-H.; Yen, C.-Y.; Shih, C.-M.; Sytwu, H.-K.; Chen, Tim-Mo; Wang, H.-J.; Williamson, M.R.; Coombes, A.G.A.

2005-01-01

Tissue engineering of skin based on collagen: PCL biocomposites using a designed co-culture system is reported. The collagen: PCL biocomposites having collagen: PCL (w/w) ratios of 1:4, 1:8, and 1:20 have been proven to be biocompatible materials to support both adult normal human epidermal Keratinocyte (NHEK) and mouse 3T3 fibroblast growth in cell culture, respectively, by Dai, Coombes, et al. in 2004. Films of collagen: PCL biocomposites were prepared using non-crosslinking method by impregnation of lyophilized collagen mats with PCL/dichloromethane solutions followed by solvent evaporation. To mimic the dermal/epidermal structure of skin, the 1:20 collagen: PCL biocomposites were selected for a feasibility study of a designed co-culture technique that would subsequently be used for preparing fibroblast/biocomposite/keratinocyte skin models. A 55.3% increase in cell number was measured in the designed co-culture system when fibroblasts were seeded on both sides of a biocomposite film compared with cell culture on one surface of the biocomposite in the feasibility study. The co-culture of human keratinocytes and 3T3 fibroblasts on each side of the membrane was therefore studied using the same co-culture system by growing keratinocytes on the top surface of membrane for 3 days and 3T3 fibroblasts underneath the membrane for 6 days. Scanning electron microscopy (SEM) and immunohistochemistry assay revealed good cell attachment and proliferation of both human keratinocytes and 3T3 fibroblasts with these two types of cells isolated well on each side of the membrane. Using a modified co-culture technique, a co-cultured skin model presenting a confluent epidermal sheet on one side of the biocomposite film and fibroblasts populated on the other side of the film was developed successfully in co-culture system for 28 days under investigations by SEM and immunohistochemistry assay. Thus, the design of a co-culture system based on 1:20 (w/w) collagen: PCL biocomposite

Culturing human intestinal stem cells for regenerative applications in the treatment of inflammatory bowel disease

DEFF Research Database (Denmark)

Holmberg, Fredrik Eo; Seidelin, Jakob B; Yin, Xiaolei

2017-01-01

models suggests that intestinal stem cell transplantation could constitute a novel treatment strategy to re-establish mucosal barrier function in patients with severe disease. Intestinal stem cells can be grownin vitroin organoid structures, though only a fraction of the cells contained are stem cells...... with regenerative capabilities. Hence, techniques to enrich stem cell populations are being pursued through the development of multiple two-dimensional and three-dimensional culture protocols, as well as co-culture techniques and multiple growth medium compositions. Moreover, research in support matrices allowing...... for efficient clinical application is in progress.In vitroculture is accomplished by modulating the signaling pathways fundamental for the stem cell niche with a suitable culture matrix to provide additional contact-dependent stimuli and structural support. The aim of this review was to discuss medium...

Preparation of labelled lipids by the use of plant cell cultures

International Nuclear Information System (INIS)

Mangold, H.K.

1978-01-01

The preparation of some radioacitvely labelled lipids by the use of plant cell cultures is discussed and further applications of the new method are suggested. Cell suspension cultures of rape (Brassica napus) and soya (Glycine max) have been used for the preparation of lipids labelled with radioisotopes. Radioactive acetic acid as well as various long-chain fatty acids are readily incorporated into the neutral and ionic lipids of plant cell cultures. In addition, 14 C-labelled glycerol, ethanolamine and choline are well utilized by the cells. Randomly labelled lipids have been obtained by incubating cell suspension cultures of rape and soya with [1- 14 C] acetic acid, and uniformly labelled lipids have been isolated from cultures that had been incubated with a mixture of [1- 14 C] acetic acid plus [2- 14 C] acetic acid. The use of techniques of plant cell cultures for the preparation of lipds labelled with stable or radioactive isotopesappears particularly rewarding because the uptake of precursors by the cells and their incorporation into various lipid compounds proceeds rapidly and often quanitatively.This new approach should be useful also for the biosynthesis of lipids whose acyl moieties contain a spn radical, a fluorescent group, or a light-sensitive label. Thus, plant cell cultures constitute valuable new tools for the biosynthetic preparation of a great variety of labelled lipids. (A.G.)

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.

Cell proliferation and radiosensitivity of cow lymphocytes in culture

International Nuclear Information System (INIS)

Modave, C.; Fabry, L.; Leonard, A.

1982-01-01

The harlequin-staining technique has been used to study, after PHA-stimulation, the cell proliferation of cow lymphocytes in culture and to assess the radiosensitivity in first mitosis cells. At the 48 h fixation time, only 34% of the cells are in first mitosis whereas 55% are already in second and 11% in third mitosis. The exposure of cow lymphocytes to 200 rad X-rays result in the production of 16% dicentric chromosomes in first mitosis cells [fr

An optimized protocol for handling and processing fragile acini cultured with the hanging drop technique.

Science.gov (United States)

Snyman, Celia; Elliott, Edith

2011-12-15

The hanging drop three-dimensional culture technique allows cultivation of functional three-dimensional mammary constructs without exogenous extracellular matrix. The fragile acini are, however, difficult to preserve during processing steps for advanced microscopic investigation. We describe adaptations to the protocol for handling of hanging drop cultures to include investigation using confocal, scanning, and electron microscopy, with minimal loss of cell culture components. Copyright © 2011 Elsevier Inc. All rights reserved.

Long-term culture of rat hippocampal neurons at low density in serum-free medium: combination of the sandwich culture technique with the three-dimensional nanofibrous hydrogel PuraMatrix.

Science.gov (United States)

Kaneko, Ai; Sankai, Yoshiyuki

2014-01-01

The primary culture of neuronal cells plays an important role in neuroscience. There has long been a need for methods enabling the long-term culture of primary neurons at low density, in defined serum-free medium. However, the lower the cell density, the more difficult it is to maintain the cells in culture. Therefore, we aimed to develop a method for long-term culture of neurons at low density, in serum-free medium, without the need for a glial feeder layer. Here, we describe the work leading to our determination of a protocol for long-term (>2 months) primary culture of rat hippocampal neurons in serum-free medium at the low density of 3×10(4) cells/mL (8.9×10(3) cells/cm2) without a glial feeder layer. Neurons were cultured on a three-dimensional nanofibrous hydrogel, PuraMatrix, and sandwiched under a coverslip to reproduce the in vivo environment, including the three-dimensional extracellular matrix, low-oxygen conditions, and exposure to concentrated paracrine factors. We examined the effects of varying PuraMatrix concentrations, the timing and presence or absence of a coverslip, the timing of neuronal isolation from embryos, cell density at plating, medium components, and changing the medium or not on parameters such as developmental pattern, cell viability, neuronal ratio, and neurite length. Using our method of combining the sandwich culture technique with PuraMatrix in Neurobasal medium/B27/L-glutamine for primary neuron culture, we achieved longer neurites (≥3,000 µm), greater cell viability (≥30%) for 2 months, and uniform culture across the wells. We also achieved an average neuronal ratio of 97%, showing a nearly pure culture of neurons without astrocytes. Our method is considerably better than techniques for the primary culture of neurons, and eliminates the need for a glial feeder layer. It also exhibits continued support for axonal elongation and synaptic activity for long periods (>6 weeks).

Long-term culture of rat hippocampal neurons at low density in serum-free medium: combination of the sandwich culture technique with the three-dimensional nanofibrous hydrogel PuraMatrix.

Directory of Open Access Journals (Sweden)

Ai Kaneko

Full Text Available The primary culture of neuronal cells plays an important role in neuroscience. There has long been a need for methods enabling the long-term culture of primary neurons at low density, in defined serum-free medium. However, the lower the cell density, the more difficult it is to maintain the cells in culture. Therefore, we aimed to develop a method for long-term culture of neurons at low density, in serum-free medium, without the need for a glial feeder layer. Here, we describe the work leading to our determination of a protocol for long-term (>2 months primary culture of rat hippocampal neurons in serum-free medium at the low density of 3×10(4 cells/mL (8.9×10(3 cells/cm2 without a glial feeder layer. Neurons were cultured on a three-dimensional nanofibrous hydrogel, PuraMatrix, and sandwiched under a coverslip to reproduce the in vivo environment, including the three-dimensional extracellular matrix, low-oxygen conditions, and exposure to concentrated paracrine factors. We examined the effects of varying PuraMatrix concentrations, the timing and presence or absence of a coverslip, the timing of neuronal isolation from embryos, cell density at plating, medium components, and changing the medium or not on parameters such as developmental pattern, cell viability, neuronal ratio, and neurite length. Using our method of combining the sandwich culture technique with PuraMatrix in Neurobasal medium/B27/L-glutamine for primary neuron culture, we achieved longer neurites (≥3,000 µm, greater cell viability (≥30% for 2 months, and uniform culture across the wells. We also achieved an average neuronal ratio of 97%, showing a nearly pure culture of neurons without astrocytes. Our method is considerably better than techniques for the primary culture of neurons, and eliminates the need for a glial feeder layer. It also exhibits continued support for axonal elongation and synaptic activity for long periods (>6 weeks.

Lethal graft-versus-host disease: modification with allogeneic cultured donor cells

International Nuclear Information System (INIS)

Mauch, P.; Lipton, J.M.; Hamilton, B.; Obbagy, J.; Kudisch, M.; Nathan, D.; Hellman, S.

1984-01-01

The use of the bone marrow culture technique was studied as a means to prepare donor marrow for bone marrow transplantation to avoid lethal graft-versus-host disease (GVHD). Preliminary experiments demonstrated the rapid loss of theta-positive cells in such cultures, so that theta-positive cells were not detected after 6 days. Initial experiments in C3H/HeJ (H-2k, Hbbd) recipients prepared with 900 rad demonstrated improved survival when 3-day cultured C57BL/6 (H-2b, Hbbs) donor cells were used in place of hind limb marrow for transplantation. However, hemoglobin typing of recipient animals revealed only short-term donor engraftment, with competitive repopulation of recipient marrow occurring. Subsequent experiments were done in 1,200-rad prepared recipients, with long-term donor engraftment demonstrated. The majority of 1,200-rad prepared animals receiving cultured allogeneic cells died of GVHD, but animals receiving 28-day cultured cells had an improved 90-day survival and a delay in GVHD development over animals receiving hind limb marrow or marrow from shorter times in culture. In addition, animals receiving anti-theta-treated, 3-day nonadherent cells had an improved survival (44%) over animals receiving anti-theta-treated hind limb marrow (20%). These experiments demonstrate modest benefit for the use of cultured cells in bone marrow transplantation across major H-2 histocompatibility complex differences

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

Science.gov (United States)

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.

Tailor-made three-dimensional hybrid scaffolds for cell cultures

International Nuclear Information System (INIS)

Psycharakis, Stylianos; Melissinaki, Vasileia; Giakoumaki, Anastasia; Ranella, Anthi; Tosca, Androniki

2011-01-01

The construction of the ideal three-dimensional scaffold for cell culture is one of the most intriguing topics in tissue engineering. It has been shown that cells can be cultured on most organic biomimetic materials, which now are losing popularity in favour of novel, hybrid systems. In this study, a series of photosensitive sol-gel hybrid materials, based on silicon-zirconium and silicon-titanium oxides, have been investigated for their suitability in three-dimensional scaffold fabrication. These materials can be structured by two-photon polymerization, a laser-based technique allowing the fabrication of micrometre-size structures with submicron resolution. The work presented here examined the effect of the organic/inorganic composition of the materials on cell behaviour and the establishment of a 'cell-culture friendly' environment. This is vital for cell adhesion, growth and differentiation, as the organic part of the material provides the soft matrix for cell growth, whereas the inorganic component gives the mechanical stability and rigidity of the three-dimensional structures. In addition, the use of femtosecond laser structuring permits the fabrication of a wide range of mechanically stable scaffolds of different sizes and shapes to be tested in terms of cell viability, proliferation and orientation.

Near-IR laser-triggered target cell collection using a carbon nanotube-based cell-cultured substrate.

Science.gov (United States)

Sada, Takao; Fujigaya, Tsuyohiko; Niidome, Yasuro; Nakazawa, Kohji; Nakashima, Naotoshi

2011-06-28

Unique near-IR optical properties of single-walled carbon nanotube (SWNTs) are of interest in many biological applications. Here we describe the selective cell detachment and collection from an SWNT-coated cell-culture dish triggered by near-IR pulse laser irradiation. First, HeLa cells were cultured on an SWNT-coated dish prepared by a spraying of an aqueous SWNT dispersion on a glass dish. The SWNT-coated dish was found to show a good cell adhesion behavior as well as a cellular proliferation rate similar to a conventional glass dish. We discovered, by near-IR pulse laser irradiation (at the laser power over 25 mW) to the cell under optical microscopic observation, a quick single-cell detachment from the SWNT-coated surface. Shockwave generation from the irradiated SWNTs is expected to play an important role for the cell detachment. Moreover, we have succeeded in catapulting the target single cell from the cultured medium when the depth of the medium was below 150 μm and the laser power was stronger than 40 mW. The captured cell maintained its original shape. The retention of the genetic information of the cell was confirmed by the polymerase chain reaction (PCR) technique. A target single-cell collection from a culture medium under optical microscopic observation is significant in wide fields of single-cell studies in biological areas.

Growing Arabidopsis in vitro: cell suspensions, in vitro culture, and regeneration.

Science.gov (United States)

Barkla, Bronwyn J; Vera-Estrella, Rosario; Pantoja, Omar

2014-01-01

An understanding of basic methods in Arabidopsis tissue culture is beneficial for any laboratory working on this model plant. Tissue culture refers to the aseptic growth of cells, organs, or plants in a controlled environment, in which physical, nutrient, and hormonal conditions can all be easily manipulated and monitored. The methodology facilitates the production of a large number of plants that are genetically identical over a relatively short growth period. Techniques, including callus production, cell suspension cultures, and plant regeneration, are all indispensable tools for the study of cellular biochemical and molecular processes. Plant regeneration is a key technology for successful stable plant transformation, while cell suspension cultures can be exploited for metabolite profiling and mining. In this chapter we report methods for the successful and highly efficient in vitro regeneration of plants and production of stable cell suspension lines from leaf explants of both Arabidopsis thaliana and Arabidopsis halleri.

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....

Pigment Cell Differentiation in Sea Urchin Blastula-Derived Primary Cell Cultures

Science.gov (United States)

Ageenko, Natalya V.; Kiselev, Konstantin V.; Dmitrenok, Pavel S.; Odintsova, Nelly A.

2014-01-01

The quinone pigments of sea urchins, specifically echinochrome and spinochromes, are known for their effective antioxidant, antibacterial, antifungal, and antitumor activities. We developed in vitro technology for inducing pigment differentiation in cell culture. The intensification of the pigment differentiation was accompanied by a simultaneous decrease in cell proliferation. The number of pigment cells was two-fold higher in the cells cultivated in the coelomic fluids of injured sea urchins than in those intact. The possible roles of the specific components of the coelomic fluids in the pigment differentiation process and the quantitative measurement of the production of naphthoquinone pigments during cultivation were examined by MALDI and electrospray ionization mass spectrometry. Echinochrome A and spinochrome E were produced by the cultivated cells of the sand dollar Scaphechinus mirabilis in all tested media, while only spinochromes were found in the cultivated cells of another sea urchin, Strongylocentrotus intermedius. The expression of genes associated with the induction of pigment differentiation was increased in cells cultivated in the presence of shikimic acid, a precursor of naphthoquinone pigments. Our results should contribute to the development of new techniques in marine biotechnology, including the generation of cell cultures producing complex bioactive compounds with therapeutic potential. PMID:24979272

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…

Effect of Co-Culturing of Mice Liver Cells and Embryonic Carcinomatous Stem Cells on the Rate of Differentiation to Hematopoietic Cells

Directory of Open Access Journals (Sweden)

AA Pourfatollah

2005-10-01

Full Text Available Introduction: Considering the importance of co-culture in differentiation of embryonic stem cells, the aim of this study was evaluation of the effect of co-culturing fetal liver stroma cells with P19 cells on the line of differentiation. Materials and Methods: For this purpose, P19 cells were cultured directly in semisolid medium. These cells proliferated and primarily differentiated to colonies know as embryoid bodies (EBs after 8-12 days. The Ebs cells were trypsinized and dissociated to single or double cells. Then these cells were co-cultured on the mouse fetal liver feeder layer in the absence of exogenous factors. After 14-18 days, the colonies were studied morphologically by benzidine and giemsa staining and also counted under invert microscope. Results: The percentages of benzidine positive (or erythroid and negative colonies were 94% and 6% respectively and also the cells of colonies were studied by Giemsa staining. Results showed that they were myeloid or lymphoid type cells. Thus, the results show that in the presence of mouse fetal liver feeder layer, the number of erythroid colonies was increased. Conclusions: Therefore, this technique may be effective for differentiation of stem cells from different sources into hematopoietic cells and can be used in future for human cell therapy.

A thin-layer liquid culture technique for the growth of Helicobacter pylori.

Science.gov (United States)

Joo, Jung-Soo; Park, Kyung-Chul; Song, Jae-Young; Kim, Dong-Hyun; Lee, Kyung-Ja; Kwon, Young-Cheol; Kim, Jung-Min; Kim, Kyung-Mi; Youn, Hee-Shang; Kang, Hyung-Lyun; Baik, Seung-Chul; Lee, Woo-Kon; Cho, Myung-Je; Rhee, Kwang-Ho

2010-08-01

Several attempts have been successful in liquid cultivation of Helicobaccter pylori. However, there is a need to improve the growth of H. pylori in liquid media in order to get affluent growth and a simple approach for examining bacterial properties. We introduce here a thin-layer liquid culture technique for the growth of H. pylori. A thin-layer liquid culture system was established by adding liquid media to a 90-mm diameter Petri dish. Optimal conditions for bacterial growth were investigated and then viability, growth curve, and released proteins were examined. Maximal growth of H. pylori was obtained by adding 3 mL of brucella broth supplemented with 10% horse to a Petri dish. H. pylori grew in both DMEM and RPMI-1640 supplemented with 10% fetal bovine serum and 0.5% yeast extract. Serum-free RPMI-1640 supported the growth of H. pylori when supplemented with dimethyl-beta-cyclodextrin (200 microg/mL) and 1% yeast extract. Under optimal growth, H. pylori grew exponentially for 28 hours, reaching a density of 3.4 OD(600) with a generation time of 3.3 hours. After 24 hours, cultures at a cell density of 1.0 OD(600) contained 1.3 +/- 0.1 x 10(9 )CFU/mL. gamma-Glutamyl transpeptidase, nuclease, superoxide dismutase, and urease were not detected in culture supernatants at 24 hours in thin-layer liquid culture, but were present at 48 hours, whereas alcohol dehydrogenase, alkylhydroperoxide reductase, catalase, and vacuolating cytotoxin were detected at 24 hours. Thin-layer liquid culture technique is feasible, and can serve as a versatile liquid culture technique for investigating bacterial properties of H. pylori.

Cultivation of murine bone marrow macrophages in sponges: a method that permits recovery of viable cultured cells

Energy Technology Data Exchange (ETDEWEB)

Akporiaye, E T; Stewart, S; Stewart, C C

1984-01-01

Various investigators have cultured murine bone marrow or peritoneal cells in vitro on glass or plastic surfaces with the ultimate aim of retrieving adherent macrophages for morphologic and functional evaluation. The removal of these adherent macrophages by conventional techniques has been consistently accompanied by low yield and significant cell damage. The authors report here a simple technique for culturing murine bone marrow cells in gelatin sponges (Spongostan and Gelfoam) in growth medium containing 10% fetal bovine serum and 10% L-cell conditioned medium. Viable cells were retrieved from the sponges in 10 min by digestion with collagenase. The in situ growth kinetics were similar to those found for cells cultured on plastic dishes. The recovered cells were adherent, phagocytic, positive for Fc ..gamma.. receptors, and had esterase activity. 23 references, 1 figure, 1 table.

Analytical techniques for characterization of raw materials in cell culture media

Directory of Open Access Journals (Sweden)

Sharma Chandana

2011-11-01

Full Text Available Abstract Raw materials are a critical part of any cell culture medium; therefore, it is of utmost importance to understand and characterize them for high-quality product. The raw material characterization (RMC program at SAFC focuses on individual screening of raw materials both analytically and biologically. The goal of the program is to develop the best-in-class knowledge base of the raw materials used in SAFC’s media formulations and their impact on performance of products.

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...

Tailor-made three-dimensional hybrid scaffolds for cell cultures

Energy Technology Data Exchange (ETDEWEB)

Psycharakis, Stylianos; Melissinaki, Vasileia; Giakoumaki, Anastasia; Ranella, Anthi [Institute of Electronic Structure and Laser, Foundation for Research and Technology Hellas, PO Box 1527, 711 10 Heraklion, Crete (Greece); Tosca, Androniki, E-mail: ranthi@iesl.forth.gr [Department of Medicine, University of Crete, 710 03 Heraklion, Crete (Greece)

2011-08-15

The construction of the ideal three-dimensional scaffold for cell culture is one of the most intriguing topics in tissue engineering. It has been shown that cells can be cultured on most organic biomimetic materials, which now are losing popularity in favour of novel, hybrid systems. In this study, a series of photosensitive sol-gel hybrid materials, based on silicon-zirconium and silicon-titanium oxides, have been investigated for their suitability in three-dimensional scaffold fabrication. These materials can be structured by two-photon polymerization, a laser-based technique allowing the fabrication of micrometre-size structures with submicron resolution. The work presented here examined the effect of the organic/inorganic composition of the materials on cell behaviour and the establishment of a 'cell-culture friendly' environment. This is vital for cell adhesion, growth and differentiation, as the organic part of the material provides the soft matrix for cell growth, whereas the inorganic component gives the mechanical stability and rigidity of the three-dimensional structures. In addition, the use of femtosecond laser structuring permits the fabrication of a wide range of mechanically stable scaffolds of different sizes and shapes to be tested in terms of cell viability, proliferation and orientation.

Automation of 3D cell culture using chemically defined hydrogels.

Science.gov (United States)

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.

Cell cycle phase of nondividing cells in aging human cell cultures determined by DNA content and chromosomal constitution

International Nuclear Information System (INIS)

Yanishevsky, R.M.

1975-01-01

Human diploid cell cultures, strain WI-38, have a finite proliferative capacity and have been proposed as a model of biological aging. To identify the cell cycle phase of the nondividing cells, cultures of various ages were exposed to 3 Hdt for 48 hours to label dividing cells, then the cycle phase was identified for individual cells by one of two methods, and finally, the proliferative status of the same cells was scored by autoradiographic evidence of 3 HdT uptake. The methods to identify the cycle phase were: determination of DNA strain content by Feulgen scanning cytophotometry, and determination of chromosome constitution by the technique of premature chromosome condensation (PCC). Preliminary experiments showed the effect of continuous exposure to various levels of 3 HdT on cell growth. High levels of 3 HdT inhibited cell cycle traverse: the cell number and labeling index curves reached a plateau; the cell volume increased; the cells accumulated with 4C DNA contents and it appeared that they blocked in G 2 phase. This pattern is consistent with a radiation effect. (U.S.)

Hand-made cloned goat (Capra hircus) embryos—a comparison of different donor cells and culture systems.

Science.gov (United States)

Akshey, Yogesh S; Malakar, Dhruba; De, Arun K; Jena, Manoj K; Garg, Shweta; Dutta, Rahul; Pawar, Sachin Kumar; Mukesh, Manisha

2010-10-01

Nuclear transfer is a very effective method for propagation of valuable, extinct, and endangered animals. Hand-made cloning (HMC) is an efficient alternative to the conventional micromanipulator-based technique in some domestic species. The present study was carried out for the selection of suitable somatic cells as a nuclear donor and development of an optimum culture system for in vitro culture of zona-free goat cloned embryos. Cleavage and blastocyst rates were observed 72.06 ± 2.94% and 0% for fresh cumulus cells, 81.95 ± 3.40% and 12.74 ± 2.12% for cultured cumulus cells, and 92.94 ± 0.91% and 23.78 ± 3.33% for fetal fibroblast cells, respectively. There was a significant (p cloned embryos and donor cells. In conclusion, the present study describes that the fetal fibroblast cell is a suitable candidate as nuclear donor, and the flat surface culture system is suitable for zona-free blastocyst development by the hand-made cloning technique in the goat.

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.

9 CFR 101.6 - Cell cultures.

Science.gov (United States)

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...

Study of the cell activity in three-dimensional cell culture by using Raman spectroscopy

Science.gov (United States)

Arunngam, Pakajiraporn; Mahardika, Anggara; Hiroko, Matsuyoshi; Andriana, Bibin Bintang; Tabata, Yasuhiko; Sato, Hidetoshi

2018-02-01

The purpose of this study is to develop a estimation technique of local cell activity in cultured 3D cell aggregate with gelatin hydrogel microspheres by using Raman spectroscopy. It is an invaluable technique allowing real-time, nondestructive, and invasive measurement. Cells in body generally exist in 3D structure, which physiological cell-cell interaction enhances cell survival and biological functions. Although a 3D cell aggregate is a good model of the cells in living tissues, it was difficult to estimate their physiological conditions because there is no effective technique to make observation of intact cells in the 3D structure. In this study, cell aggregates were formed by MC3T-E1 (pre-osteoblast) cells and gelatin hydrogel microspheres. In appropriate condition MC3T-E1 cells can differentiate into osteoblast. We assume that the activity of the cell would be different according to the location in the aggregate because the cells near the surface of the aggregate have more access to oxygen and nutrient. Raman imaging technique was applied to measure 3D image of the aggregate. The concentration of the hydroxyapatite (HA) is generated by osteoblast was estimated with a strong band at 950-970 cm-1 which assigned to PO43- in HA. It reflects an activity of the specific site in the cell aggregate. The cell density in this specific site was analyzed by multivariate analysis of the 3D Raman image. Hence, the ratio between intensity and cell density in the site represents the cell activity.

Primary culture of human Schwann and schwannoma cells: improved and simplified protocol.

Science.gov (United States)

Dilwali, Sonam; Patel, Pratik B; Roberts, Daniel S; Basinsky, Gina M; Harris, Gordon J; Emerick, Kevin S; Stankovic, Konstantina M

2014-09-01

Primary culture of human Schwann cells (SCs) and vestibular schwannoma (VS) cells are invaluable tools to investigate SC physiology and VS pathobiology, and to devise effective pharmacotherapies against VS, which are sorely needed. However, existing culture protocols, in aiming to create robust, pure cultures, employ methods that can lead to loss of biological characteristics of the original cells, potentially resulting in misleading biological findings. We have developed a minimally manipulative method to culture primary human SC and VS cells, without the use of selective mitogens, toxins, or time-consuming and potentially transformative laboratory techniques. Schwann cell purity was quantified longitudinally using S100 staining in SC cultures derived from the great auricular nerve and VS cultures followed for 7 and 12 weeks, respectively. SC cultures retained approximately ≥85% purity for 2 weeks. VS cultures retained approximately ≥80% purity for the majority of the span of 12 weeks, with maximal purity of 87% at 2 weeks. The VS cultures showed high level of biological similarity (68% on average) to their respective parent tumors, as assessed using a protein array featuring 41 growth factors and receptors. Apoptosis rate in vitro negatively correlated with tumor volume. Our results, obtained using a faster, simplified culturing method than previously utilized, indicate that highly pure, primary human SC and VS cultures can be established with minimal manipulation, reaching maximal purity at 2 weeks of culture. The VS cultures recapitulate the parent tumors' biology to a great degree, making them relevant models to investigate VS pathobiology. Copyright © 2014 Elsevier B.V. All rights reserved.

A flexible thermoresponsive cell culture substrate for direct transfer of keratinocyte cell sheets.

Science.gov (United States)

Praveen, Wulligundam; Madathil, Bernadette K; Sajin Raj, R S; Kumary, T V; Anil Kumar, P R

2017-10-25

Most cell sheet engineering systems require a support or carrier to handle the harvested cell sheets. In this study, polyethylene terephthalate-based overhead projection transparency sheets (OHPS) were subjected to surface hydrolysis by alkali treatment to increase pliability and hydrophilicity and enable poly(N-isopropylacrylamide-co-glycidylmethacrylate) copolymer (NGMA) coating to impart thermoresponsiveness. NGMA was applied on the modified OHPS by the technique of spin coating using an indigenously designed spin coater. The spin coating had the advantage of using low volumes of the polymer and a reduced coating time. The surface chemistry and thermoresponsive coating was analyzed by Fourier transform infrared spectroscopy and water contact angle. Human keratinocyte cells were cultured on the spin coated surface and scaffold-free cell sheets were successfully harvested by simple variation of temperature. These cell sheets were found to be viable, exhibited epithelial characteristic and cell-cell contact as confirmed by positive immunostaining for ZO-1. The integrity and morphology of the cell sheet was confirmed by stereomicroscopy and E-SEM. These results highlight the potential of the NGMA spin coated modified OHPS to serve as a thermoresponsive culture surface-cum-flexible transfer tool.

Handbook of plant cell culture. Volume 2. Crop species

Energy Technology Data Exchange (ETDEWEB)

Sharp, W.R.; Evans, D.A.; Ammirato, P.V.; Yamada, Y. (eds.)

1984-01-01

In this volume the state-of-the-art plant cell culture techniques described in the first volume are applied to several agricultural and horticultural crops. In 21 chapters, they include maize, oats, wheat, beans, red clover and other forage legumes, asparagus, celery, cassava, sweet potato, banana, pawpaw, apple, grapes, conifers, date palm, rubber, sugarcane and tobacco. Each chapter contains (1) detailed protocols to serve as the foundation for current research, (2) a critical review of the literature, and (3) in-depth evaluations of the potential shown by plant cell culture for crop improvement. The history and economic importance of each crop are discussed. This volume also includes an essay, ''Oil from plants'', by M. Calvin.

Apple derived cellulose scaffolds for 3D mammalian cell culture.

Directory of Open Access Journals (Sweden)

Daniel J Modulevsky

Full Text Available There are numerous approaches for producing natural and synthetic 3D scaffolds that support the proliferation of mammalian cells. 3D scaffolds better represent the natural cellular microenvironment and have many potential applications in vitro and in vivo. Here, we demonstrate that 3D cellulose scaffolds produced by decellularizing apple hypanthium tissue can be employed for in vitro 3D culture of NIH3T3 fibroblasts, mouse C2C12 muscle myoblasts and human HeLa epithelial cells. We show that these cells can adhere, invade and proliferate in the cellulose scaffolds. In addition, biochemical functionalization or chemical cross-linking can be employed to control the surface biochemistry and/or mechanical properties of the scaffold. The cells retain high viability even after 12 continuous weeks of culture and can achieve cell densities comparable with other natural and synthetic scaffold materials. Apple derived cellulose scaffolds are easily produced, inexpensive and originate from a renewable source. Taken together, these results demonstrate that naturally derived cellulose scaffolds offer a complementary approach to existing techniques for the in vitro culture of mammalian cells in a 3D environment.

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

Science.gov (United States)

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.

Science.gov (United States)

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.

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

Directory of Open Access Journals (Sweden)

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.

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.

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.

Production of monozygotic twin calves using the blastomere separation technique and Well of the Well culture system.

Science.gov (United States)

Tagawa, M; Matoba, S; Narita, M; Saito, N; Nagai, T; Imai, K

2008-03-15

The present study was conducted to establish a simple and efficient method of producing monozygotic twin calves using the blastomere separation technique. To produce monozygotic twin embryos from zona-free two- and eight-cell embryos, blastomeres were separated mechanically by pipetting to form two demi-embryos; each single blastomere from the two-cell embryo and tetra-blastomeres from the eight-cell embryo were cultured in vitro using the Well of the Well culture system (WOW). This culture system supported the successful arrangement of blastomeres, resulting in their subsequent aggregation to form a demi-embryo developing to the blastocyst stage without a zona pellucida. There was no significant difference in the development to the blastocyst stage between blastomeres separated from eight-cell (72.0%) and two-cell (62.0%) embryos. The production rates of the monozygotic pair blastocysts and transferable paired blastocysts for demi-embryos obtained from eight-cell embryos (64.0 and 45.0%, respectively) were higher than those for demi-embryos obtained from two-cell embryos (49.0 and 31.0%, PWOW culture system, yielded viable monozygotic demi-embryos, resulting in high rates of pregnancy and twinning rates after embryo transfer.

Cell-cycle research with synchronous cultures: an evaluation

Science.gov (United States)

Helmstetter, C. E.; Thornton, M.; Grover, N. B.

2001-01-01

The baby-machine system, which produces new-born Escherichia coli cells from cultures immobilized on a membrane, was developed many years ago in an attempt to attain optimal synchrony with minimal disturbance of steady-state growth. In the present article, we put forward a model to describe the behaviour of cells produced by this method, and provide quantitative evaluation of the parameters involved, at each of four different growth rates. Considering the high level of selection achievable with this technique and the natural dispersion in interdivision times, we believe that the output of the baby machine is probably close to optimal in terms of both quality and persistence of synchrony. We show that considerable information on events in the cell cycle can be obtained from populations with age distributions very much broader than those achieved with the baby machine and differing only modestly from steady state. The data presented here, together with the long and fruitful history of findings employing the baby-machine technique, suggest that minimisation of stress on cells is the single most important factor for successful cell-cycle analysis.

Characterization of A Three-Dimensional Organotypic Co-Culture Skin Model for Epidermal Differentiation of Rat Adipose-Derived Stem Cells.

Science.gov (United States)

Ghanavati, Zeinab; Orazizadeh, Mahmoud; Bayati, Vahid; Abbaspour, Mohammad Reza; Khorsandi, Layasadat; Mansouri, Esrafil; Neisi, Niloofar

2016-01-01

The organotypic co-culture is a well-known technique to examine cellular interactions and their roles in stem cell proliferation and differentiation. This study aims to evaluate the effects of dermal fibroblasts (DFs) on epidermal differentiation of adipose-derived stem cells (ASCs) using a three-dimensional (3D) organotypic co- culture technique. In this experimental research study, rat DFs and ASCs were isolated and cultured separately on electrospun polycaprolactone (PCL) matrices. The PCL matrices seeded by ASCs were superimposed on to the matrices seeded by DFs in order to create a 3D organotypic co-culture. In the control groups, PCL matrices seeded by ASCs were placed on matrices devoid of DFs. After 10 days, we assessed the expressions of keratinocyte-related genes by real-time reverse transcriptase-polymerase chain reaction (RT-PCR) and expression of pan-cytokeratin protein by immunofluorescence in the differentiated keratinocyte-like cells from co- culture and control groups. Keratinocyte-like cell morphologies were also observed by scanning electron microscopy (SEM). The early, intermediate, and terminal differentiation keratinocyte markers-Cytokeratin14, Filaggrin, and Involucrin significantly expressed in the co-culture groups com- pared to the control ones (P<0.05). We observed pan-cytokeratin in keratinocyte-like cells of both groups by immunofluorescence. SEM observation of the co-culture groups showed that the differentiated keratinocyte-like cells developed a polygonal cobblestone shape, considered characteristic of keratinocytes. The 3D organotypic co-culture bilayered construct that consisted of DFs and ASCs was an effective technique for epidermal differentiation of ASCs. This co-culture might be useful for epidermal differentiation of stem cells for future applications in skin regeneration.

Nonlinear Dielectric Properties of Yeast Cells Cultured in Different Environmental Conditions

Science.gov (United States)

Kawanishi, Gomon; Fukuda, Naoki; Muraji, Masafumi

The harmonics of the electric current through yeast suspensions, the nonlinear dielectric properties of yeast cells, have particular patterns according to the biological activity of the cells and the measurement of these patterns is a technique for determining the activity of living cells. The concentration of glucose and oxygen in yeast culture medium influences the manifestation of fermentation or respiration of yeast cells. Measurements were made with yeast cells (Saccharomyces cerevisiae) cultured aerobically and anaerobically in sufficient glucose concentration, aerobic fermentation and anaerobic fermentation, and aerobically in limited glucose concentration, respiration. The results showed that the harmonics were barely apparent for yeast cells in aerobic fermentation and respiratory; however, cells in the anaerobic fermentation displayed substantial third and fifth harmonics. We can say that environmental condition affects the yeast cells' nonlinear properties, from another viewpoint, the measurements of the nonlinear properties are available to determine the activity of yeast cells adjusted to the conditions of their cultivation.

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

Ex vivo electroporation of retinal cells: a novel, high efficiency method for functional studies in primary retinal cultures.

Science.gov (United States)

Vergara, M Natalia; Gutierrez, Christian; O'Brien, David R; Canto-Soler, M Valeria

2013-04-01

Primary retinal cultures constitute valuable tools not only for basic research on retinal cell development and physiology, but also for the identification of factors or drugs that promote cell survival and differentiation. In order to take full advantage of the benefits of this system it is imperative to develop efficient and reliable techniques for the manipulation of gene expression. However, achieving appropriate transfection efficiencies in these cultures has remained challenging. The purpose of this work was to develop and optimize a technique that would allow the transfection of chick retinal cells with high efficiency and reproducibility for multiple applications. We developed an ex vivo electroporation method applied to dissociated retinal cell cultures that offers a significant improvement over other currently available transfection techniques, increasing efficiency by five-fold. In this method, eyes were enucleated, devoid of RPE, and electroporated with GFP-encoding plasmids using custom-made electrodes. Electroporated retinas were then dissociated into single cells and plated in low density conditions, to be analyzed after 4 days of incubation. Parameters such as voltage and number of electric pulses, as well as plasmid concentration and developmental stage of the animal were optimized for efficiency. The characteristics of the cultures were assessed by morphology and immunocytochemistry, and cell viability was determined by ethidium homodimer staining. Cell imaging and counting was performed using an automated high-throughput system. This procedure resulted in transfection efficiencies in the order of 22-25% of cultured cells, encompassing both photoreceptors and non-photoreceptor neurons, and without affecting normal cell survival and differentiation. Finally, the feasibility of the technique for cell-autonomous studies of gene function in a biologically relevant context was tested by carrying out gain and loss-of-function experiments for the

In vitro expansion and differentiation of rat pancreatic duct-derived stem cells into insulin secreting cells using a dynamicthree-dimensional cell culture system.

Science.gov (United States)

Chen, X C; Liu, H; Li, H; Cheng, Y; Yang, L; Liu, Y F

2016-06-27

In this study, a dynamic three-dimensional cell culture technology was used to expand and differentiate rat pancreatic duct-derived stem cells (PDSCs) into islet-like cell clusters that can secrete insulin. PDSCs were isolated from rat pancreatic tissues by in situ collagenase digestion and density gradient centrifugation. Using a dynamic three-dimensional culture technique, the cells were expanded and differentiated into functional islet-like cell clusters, which were characterized by morphological and phenotype analyses. After maintaining 1 x 108 isolated rat PDSCs in a dynamic three-dimensional cell culture for 7 days, 1.5 x 109 cells could be harvested. Passaged PDSCs expressed markers of pancreatic endocrine progenitors, including CD29 (86.17%), CD73 (90.73%), CD90 (84.13%), CD105 (78.28%), and Pdx-1. Following 14 additional days of culture in serum-free medium with nicotinamide, keratinocyte growth factor (KGF), and b fibroblast growth factor (FGF), the cells were differentiated into islet-like cell clusters (ICCs). The ICC morphology reflected that of fused cell clusters. During the late stage of differentiation, representative clusters were non-adherent and expressed insulin indicated by dithizone (DTZ)-positive staining. Insulin was detected in the extracellular fluid and cytoplasm of ICCs after 14 days of differentiation. Additionally, insulin levels were significantly higher at this time compared with the levels exhibited by PDSCs before differentiation (P cell culture system, PDSCs can be expanded in vitro and can differentiate into functional islet-like cell clusters.

Investigating the diversity of Pseudomonas spp. in soil using culture dependent and independent techniques

DEFF Research Database (Denmark)

Li, Lili; Abu Al-Soud, Waleed; Bergmark, Lasse

2013-01-01

Less than 1% of bacterial populations present in environmental samples are culturable, meaning that cultivation will lead to an underestimation of total cell counts and total diversity. However, it is less clear whether this is also true for specific well-defined groups of bacteria for which sele...... selective culture media is available. In this study, we use culture dependent and independent techniques to describe whether isolation of Pseudomonas spp. on selective nutrient-poor NAA 1: 100 agar-medium can reflect the full diversity, found by ...

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.

Human adipose-derived stromal/stem cell isolation, culture, and osteogenic differentiation.

Science.gov (United States)

Qureshi, Ammar T; Chen, Cong; Shah, Forum; Thomas-Porch, Caasy; Gimble, Jeffrey M; Hayes, Daniel J

2014-01-01

Annually, more than 200,000 elective liposuction procedures are performed in the United States and over a million worldwide. The ease of harvest and abundance make human adipose-derived stromal/stem cells (hASCs) isolated from lipoaspirates an attractive, readily available source of adult stem cells that have become increasingly popular for use in many studies. Here, we describe common methods for hASC culture, preservation, and osteogenic differentiation. We introduce methods of ceramic, polymer, and composite scaffold synthesis with a description of morphological, chemical, and mechanical characterization techniques. Techniques for scaffold loading are compared, and methods for determining cell loading efficiency and proliferation are described. Finally, we provide both qualitative and quantitative techniques for in vitro assessment of hASC osteogenic differentiation. © 2014 Elsevier Inc. All rights reserved.

Tissue culture as a plant production technique for horticultural crops ...

African Journals Online (AJOL)

Over 100 years ago, Haberlandt envisioned the concept of plant tissue culture and provided the groundwork for the cultivation of plant cells, tissues and organs in culture. Initially plant tissue cultures arose as a research tool and focused on attempts to culture and study the development of small, isolated cells and segments ...

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)

Magnetically levitated mesenchymal stem cell spheroids cultured with a collagen gel maintain phenotype and quiescence

Directory of Open Access Journals (Sweden)

Natasha S Lewis

2017-04-01

Full Text Available Multicellular spheroids are an established system for three-dimensional cell culture. Spheroids are typically generated using hanging drop or non-adherent culture; however, an emerging technique is to use magnetic levitation. Herein, mesenchymal stem cell spheroids were generated using magnetic nanoparticles and subsequently cultured within a type I collagen gel, with a view towards developing a bone marrow niche environment. Cells were loaded with magnetic nanoparticles, and suspended beneath an external magnet, inducing self-assembly of multicellular spheroids. Cells in spheroids were viable and compared to corresponding monolayer controls, maintained stem cell phenotype and were quiescent. Interestingly, core spheroid necrosis was not observed, even with increasing spheroid size, in contrast to other commonly used spheroid systems. This mesenchymal stem cell spheroid culture presents a potential platform for modelling in vitro bone marrow stem cell niches, elucidating interactions between cells, as well as a useful model for drug delivery studies.

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...

Advanced Good Cell Culture Practice for human primary, stem cell-derived and organoid models as well as microphysiological systems.

Science.gov (United States)

Pamies, David; Bal-Price, Anna; Chesné, Christophe; Coecke, Sandra; Dinnyes, Andras; Eskes, Chantra; Grillari, Regina; Gstraunthaler, Gerhard; Hartung, Thomas; Jennings, Paul; Leist, Marcel; Martin, Ulrich; Passier, Robert; Schwamborn, Jens C; Stacey, Glyn N; Ellinger-Ziegelbauer, Heidrun; Daneshian, Mardas

2018-04-13

A major reason for the current reproducibility crisis in the life sciences is the poor implementation of quality control measures and reporting standards. Improvement is needed, especially regarding increasingly complex in vitro methods. Good Cell Culture Practice (GCCP) was an effort from 1996 to 2005 to develop such minimum quality standards also applicable in academia. This paper summarizes recent key developments in in vitro cell culture and addresses the issues resulting for GCCP, e.g. the development of induced pluripotent stem cells (iPSCs) and gene-edited cells. It further deals with human stem-cell-derived models and bioengineering of organo-typic cell cultures, including organoids, organ-on-chip and human-on-chip approaches. Commercial vendors and cell banks have made human primary cells more widely available over the last decade, increasing their use, but also requiring specific guidance as to GCCP. The characterization of cell culture systems including high-content imaging and high-throughput measurement technologies increasingly combined with more complex cell and tissue cultures represent a further challenge for GCCP. The increasing use of gene editing techniques to generate and modify in vitro culture models also requires discussion of its impact on GCCP. International (often varying) legislations and market forces originating from the commercialization of cell and tissue products and technologies are further impacting on the need for the use of GCCP. This report summarizes the recommendations of the second of two workshops, held in Germany in December 2015, aiming map the challenge and organize the process or developing a revised GCCP 2.0.

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

Reversible gelling culture media for in-vitro cell culture in three-dimensional matrices

Science.gov (United States)

An, Yuehuei H.; Mironov, Vladimir A.; Gutowska, Anna

2000-01-01

A gelling cell culture medium useful for forming a three dimensional matrix for cell culture in vitro is prepared by copolymerizing an acrylamide derivative with a hydrophilic comonomer to form a reversible (preferably thermally reversible) gelling linear random copolymer in the form of a plurality of linear chains having a plurality of molecular weights greater than or equal to a minimum gelling molecular weight cutoff, mixing the copolymer with an aqueous solvent to form a reversible gelling solution and adding a cell culture medium to the gelling solution to form the gelling cell culture medium. Cells such as chondrocytes or hepatocytes are added to the culture medium to form a seeded culture medium, and temperature of the medium is raised to gel the seeded culture medium and form a three dimensional matrix containing the cells. After propagating the cells in the matrix, the cells may be recovered by lowering the temperature to dissolve the matrix and centrifuging.

Nuclear techniques and in vitro culture for plant improvement

International Nuclear Information System (INIS)

1986-01-01

The continuous series of food shortages in many parts of the world have led scientists to consider the possibilities of using the new techniques to develop better varieties of plants. The basis for plant breeding is suitable genetic variability and mutation induction as the means to create additional variation. In vitro techniques are a relatively new tool in practical plant breeding. These Proceedings contain 62 papers and posters presented at the symposium, as well as excerpts from the discussions. The Symposium presentations are divided into the following sessions: Genetic variation from in vitro culture; Genetic stability of in vitro cultures; In vitro culture with application of mutagens; Haploids; In vitro mutant selection; Use of genetic variation derived by in vitro culture; In vitro techniques as aids in mutation breeding and Genetic engineering. A separate abstract is prepared for each of these papers and posters

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

Examining live cell cultures during apoptosis by digital holographic phase imaging and Raman spectroscopy

Science.gov (United States)

Khmaladze, Alexander

2017-11-01

Cellular apoptosis is a unique, organized series of events, leading to programmed cell death. In this work, we present a combined digital holography/Raman spectroscopy technique to study live cell cultures during apoptosis. Digital holographic microscopy measurements of live cell cultures yield information about cell shape and volume, changes to which are indicative of alterations in cell cycle and initiation of cell death mechanisms. Raman spectroscopic measurements provide complementary information about cells, such as protein, lipid and nucleic acid content, and the spectral signatures associated with structural changes in molecules. Our work indicates that the chemical changes in proteins, which were detected by Raman measurements, preceded morphological changes, which were seen with digital holographic microscopy.

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.

Multiweek cell culture project for use in upper-level biology laboratories.

Science.gov (United States)

Marion, Rebecca E; Gardner, Grant E; Parks, Lisa D

2012-06-01

This article describes a laboratory protocol for a multiweek project piloted in a new upper-level biology laboratory (BIO 426) using cell culture techniques. Human embryonic kidney-293 cells were used, and several culture media and supplements were identified for students to design their own experiments. Treatments included amino acids, EGF, caffeine, epinephrine, heavy metals, and FBS. Students researched primary literature to determine their experimental variables, made their own solutions, and treated their cells over a period of 2 wk. Before this, a sterile technique laboratory was developed to teach students how to work with the cells and minimize contamination. Students designed their experiments, mixed their solutions, seeded their cells, and treated them with their control and experimental media. Students had the choice of manipulating a number of variables, including incubation times, exposure to treatment media, and temperature. At the end of the experiment, students observed the effects of their treatment, harvested and dyed their cells, counted relative cell numbers in control and treatment flasks, and determined the ratio of living to dead cells using a hemocytometer. At the conclusion of the experiment, students presented their findings in a poster presentation. This laboratory can be expanded or adapted to include additional cell lines and treatments. The ability to design and implement their own experiments has been shown to increase student engagement in the biology-related laboratory activities as well as develop the critical thinking skills needed for independent research.

Culture of human intestinal epithelial cell using the dissociating enzyme thermolysin and endothelin-3

Directory of Open Access Journals (Sweden)

Z. Liu

2010-05-01

Full Text Available Epithelium, a highly dynamic system, plays a key role in the homeostasis of the intestine. However, thus far a human intestinal epithelial cell line has not been established in many countries. Fetal tissue was selected to generate viable cell cultures for its sterile condition, effective generation, and differentiated character. The purpose of the present study was to culture human intestinal epithelial cells by a relatively simple method. Thermolysin was added to improve the yield of epithelial cells, while endothelin-3 was added to stimulate their growth. By adding endothelin-3, the achievement ratio (viable cell cultures/total cultures was enhanced to 60% of a total of 10 cultures (initiated from 8 distinct fetal small intestines, allowing the generation of viable epithelial cell cultures. Western blot, real-time PCR and immunofluorescent staining showed that cytokeratins 8, 18 and mouse intestinal mucosa-1/39 had high expression levels in human intestinal epithelial cells. Differentiated markers such as sucrase-isomaltase, aminopeptidase N and dipeptidylpeptidase IV also showed high expression levels in human intestinal epithelial cells. Differentiated human intestinal epithelial cells, with the expression of surface markers (cytokeratins 8, 18 and mouse intestinal mucosa-1/39 and secretion of cytokines (sucrase-isomaltase, aminopeptidase N and dipeptidylpeptidase IV, may be cultured by the thermolysin and endothelin-3 method and maintained for at least 20 passages. This is relatively simple, requiring no sophisticated techniques or instruments, and may have a number of varied applications.

Effects of microirradiation of heart cells in culture at the mitochondrial level

International Nuclear Information System (INIS)

Salet, Christian; Moreno, Giuliana; Lampidis, T.J.

1980-01-01

The technique of micro-irradiation has been applied in irradiating the nucleus or the mitochondria of heart cells in tissue culture. Using classical or stimulated (laser) sources, variations in the beating rate have been utilized as an endpoint in assaying effects of micro-irradiation on the function of cardiac cells. The most important target for the stimulation of the beating rate of heart cells in vitro is the mitochondrion. When the mitochondrial oxidative system is perturbed with either KCN, ATP or adriamycin this stimulating effect is inhibited. Consequently, this combination of micro-irradiation and beating heart cells in culture is a powerful tool in determining the localization and investigating the mechanism of action of various drugs at the mitochondrial level

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

Science.gov (United States)

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.

The Effect of Spaceflight on Bone Cell Cultures

Science.gov (United States)

Landis, William J.

1999-01-01

Understanding the response of bone to mechanical loading (unloading) is extremely important in defining the means of adaptation of the body to a variety of environmental conditions such as during heightened physical activity or in extended explorations of space or the sea floor. The mechanisms of the adaptive response of bone are not well defined, but undoubtedly they involve changes occurring at the cellular level of bone structure. This proposal has intended to examine the hypothesis that the loading (unloading) response of bone is mediated by specific cells through modifications of their activity cytoskeletal elements, and/or elaboration of their extracellular matrices. For this purpose, this laboratory has utilized the results of a number of previous studies defining molecular biological, biochemical, morphological, and ultrastructural events of the reproducible mineralization of a primary bone cell (osteoblast) culture system under normal loading (1G gravity level). These data and the culture system then were examined following the use of the cultures in two NASA shuttle flights, STS-59 and STS-63. The cells collected from each of the flights were compared to respective synchronous ground (1G) control cells examined as the flight samples were simultaneously analyzed and to other control cells maintained at 1G until the time of shuttle launch, at which point they were terminated and studied (defined as basal cells). Each of the cell cultures was assayed in terms of metabolic markers- gene expression; synthesis and secretion of collagen and non-collagenous proteins, including certain cytoskeletal components; assembly of collagen into macrostructural arrays- formation of mineral; and interaction of collagen and mineral crystals during calcification of the cultures. The work has utilized a combination of biochemical techniques (radiolabeling, electrophoresis, fluorography, Western and Northern Blotting, and light microscopic immunofluorescence) and structural

Differentiation of mammalian skeletal muscle cells cultured on microcarrier beads in a rotating cell culture system

Science.gov (United States)

Torgan, C. E.; Burge, S. S.; Collinsworth, A. M.; Truskey, G. A.; Kraus, W. E.

2000-01-01

The growth and repair of adult skeletal muscle are due in part to activation of muscle precursor cells, commonly known as satellite cells or myoblasts. These cells are responsive to a variety of environmental cues, including mechanical stimuli. The overall goal of the research is to examine the role of mechanical signalling mechanisms in muscle growth and plasticity through utilisation of cell culture systems where other potential signalling pathways (i.e. chemical and electrical stimuli) are controlled. To explore the effects of decreased mechanical loading on muscle differentiation, mammalian myoblasts are cultured in a bioreactor (rotating cell culture system), a model that has been utilised to simulate microgravity. C2C12 murine myoblasts are cultured on microcarrier beads in a bioreactor and followed throughout differentiation as they form a network of multinucleated myotubes. In comparison with three-dimensional control cultures that consist of myoblasts cultured on microcarrier beads in teflon bags, myoblasts cultured in the bioreactor exhibit an attenuation in differentiation. This is demonstrated by reduced immunohistochemical staining for myogenin and alpha-actinin. Western analysis shows a decrease, in bioreactor cultures compared with control cultures, in levels of the contractile proteins myosin (47% decrease, p < 0.01) and tropomyosin (63% decrease, p < 0.01). Hydrodynamic measurements indicate that the decrease in differentiation may be due, at least in part, to fluid stresses acting on the myotubes. In addition, constraints on aggregate size imposed by the action of fluid forces in the bioreactor affect differentiation. These results may have implications for muscle growth and repair during spaceflight.

A novel method to generate and culture human mast cells: Peripheral CD34+ stem cell-derived mast cells (PSCMCs).

Science.gov (United States)

Schmetzer, Oliver; Valentin, Patricia; Smorodchenko, Anna; Domenis, Rossana; Gri, Giorgia; Siebenhaar, Frank; Metz, Martin; Maurer, Marcus

2014-11-01

The identification and characterization of human mast cell (MC) functions are hindered by the shortage of MC populations suitable for investigation. Here, we present a novel technique for generating large numbers of well differentiated and functional human MCs from peripheral stem cells (=peripheral stem cell-derived MCs, PSCMCs). Innovative and key features of this technique include 1) the use of stem cell concentrates, which are routinely discarded by blood banks, as the source of CD34+ stem cells, 2) cell culture in serum-free medium and 3) the addition of LDL as well as selected cytokines. In contrast to established and published protocols that use CD34+ or CD133+ progenitor cells from full blood, we used a pre-enriched cell population obtained from stem cell concentrates, which yielded up to 10(8) differentiated human MCs per batch after only three weeks of culture starting with 10(6) total CD34+ cells. The total purity on MCs (CD117+, FcεR1+) generated by this method varied between 55 and 90%, of which 4-20% were mature MCs that contain tryptase and chymase and show expression of FcεRI and CD117 in immunohistochemistry. PSCMCs showed robust histamine release in response to stimulation with anti-FcεR1 or IgE/anti-IgE, and increased proliferation and differentiation in response to IL-1β or IFN-γ. Taken together, this new protocol of the generation of large numbers of human MCs provides for an innovative and suitable option to investigate the biology of human MCs. Copyright © 2014 Elsevier B.V. All rights reserved.

A method for establishing human primary gastric epithelial cell culture from fresh surgical gastric tissues.

Science.gov (United States)

Aziz, Faisal; Yang, Xuesong; Wen, Qingping; Yan, Qiu

2015-08-01

At present, biopsy specimens, cancer cell lines and tissues obtained by gastric surgery are used in the study and analysis of gastric cancer, including the molecular mechanisms and proteomics. However, fibroblasts and other tissue components may interfere with these techniques. Therefore, the present study aimed to develop a procedure for the isolation of viable human gastric epithelial cells from gastric surgical tissues. A method was developed to culture human gastric epithelial cells using fresh, surgically excised tissues and was evaluated using immunocytochemistry, periodic acid-Schiff (PAS) staining and cell viability assays. Low cell growth was observed surrounding the gastric tissue on the seventh day of tissue explant culture. Cell growth subsequently increased, and at 12 days post-explant a high number of pure epithelial cells were detected. The gastric cancer cells exhibited rapid growth with a doubling time of 13-52 h, as compared to normal cells, which had a doubling time of 20-53 h. Immunocytochemical analyses of primary gastric cells revealed positive staining for cytokeratin 18 and 19, which indicated that the culture was comprised of pure epithelial cells and contained no fibroblasts. Furthermore, PAS staining demonstrated that the cultured gastric cells produced neutral mucin. Granulin and carbohydrate antigen 724 staining confirmed the purity of gastric cancer and normal cells in culture. This method of cell culture indicated that the gastric cells in primary culture consisted of mucin-secreting gastric epithelial cells, which may be useful for the study of gastric infection with Helicobacter pylori and gastric cancer.

Rapid fabricating technique for multi-layered human hepatic cell sheets by forceful contraction of the fibroblast monolayer.

Directory of Open Access Journals (Sweden)

Yusuke Sakai

Full Text Available Cell sheet engineering is attracting attention from investigators in various fields, from basic research scientists to clinicians focused on regenerative medicine. However, hepatocytes have a limited proliferation potential in vitro, and it generally takes a several days to form a sheet morphology and multi-layered sheets. We herein report our rapid and efficient technique for generating multi-layered human hepatic cell (HepaRG® cell sheets using pre-cultured fibroblast monolayers derived from human skin (TIG-118 cells as a feeder layer on a temperature-responsive culture dish. Multi-layered TIG-118/HepaRG cell sheets with a thick morphology were harvested on day 4 of culturing HepaRG cells by forceful contraction of the TIG-118 cells, and the resulting sheet could be easily handled. In addition, the human albumin and alpha 1-antitrypsin synthesis activities of TIG-118/HepaRG cells were approximately 1.2 and 1.3 times higher than those of HepaRG cells, respectively. Therefore, this technique is considered to be a promising modality for rapidly fabricating multi-layered human hepatocyte sheets from cells with limited proliferation potential, and the engineered cell sheet could be used for cell transplantation with highly specific functions.

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

A novel porcine cell culture based protocol for the propagation of hepatitis E virus

Directory of Open Access Journals (Sweden)

Walter Chingwaru

2016-08-01

Full Text Available Objective: To present a comprehensive protocol for the processing of hepatitis E virus (HEV infected samples and propagation of the virus in primary cell cultures. Methods: Hepatitis E was extracted from porcine liver and faecal samples following standard protocols. The virus was then allowed to attach in the presence of trypsin to primary cells that included porcine and bovine intestinal epithelial cells and macrophages over a period of up to 3 h. The virus was propagated by rotational passaging through the cell cultures. Propagation was confirmed by immunoblotting. Results: We developed a comprehensive protocol to propagate HEV in porcine cell model that includes (i rotational culturing of the virus between porcine cell types, (ii pre-incubation of infected cells for 210 min, (iii use of a semi-complete cell culture medium supplemented with trypsin (0.33 µg/mL and (iv the use of simple immunoblot technique to detect the amplified virus based on the open reading frame 2/3. Conclusions: This protocol opens doors towards systematic analysis of the mechanisms that underlie the pathogenesis of HEV in vitro. Using our protocol, one can complete the propagation process within 6 to 9 d.

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

In vitro differentiation of bone marrow stromal cells into neurons and glial cells and differential protein expression in a two-compartment bone marrow stromal cell/neuron co-culture system.

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Qi, Xu; Shao, Ming; Peng, Haisheng; Bi, Zhenggang; Su, Zhiqiang; Li, Hulun

2010-07-01

This study was performed to establish a bone marrow stromal cell (BMSC)/neuron two-compartment co-culture model in which differentiation of BMSCs into neurons could occur without direct contact between the two cell types, and to investigate protein expression changes during differentiation of this entirely BMSC-derived population. Cultured BMSCs isolated from Wistar rats were divided into three groups: BMSC culture, BMSC/neuron co-culture and BMSC/neuron two-compartment co-culture. Cells were examined for neuron-specific enolase (NSE) and glial fibrillary acidic protein (GFAP) expression. The electrophysiological behavior of the BMSCs was examined using patch clamping. Proteins that had significantly different expression levels in BMSCs cultured alone and co-cultured with neurons were studied using a protein chip-mass spectroscopy technique. Expression of NSE and GFAP were significantly higher in co-culture cells than in two-compartment co-culture cells, and significantly higher in both co-culture groups than in BMSCs cultured alone. Five proteins showed significant changes in expression during differentiation: TIP39_RAT and CALC_RAT underwent increases, and INSL6_RAT, PNOC_RAT and PCSK1_RAT underwent decreases in expression. We conclude that BMSCs can differentiate into neurons during both contact co-culture with neurons and two-compartment co-culture with neurons. The rate at which BMSCs differentiated into neurons was higher in contact co-culture than in non-contact co-culture.

Adaptation of a Commonly Used, Chemically Defined Medium for Human Embryonic Stem Cells to Stable Isotope Labeling with Amino Acids in Cell Culture

DEFF Research Database (Denmark)

Liberski, A. R.; Al-Noubi, M. N.; Rahman, Z. H.

2013-01-01

Metabolic labeling with stable isotopes is a prominent technique for comparative quantitative proteomics, and stable isotope labeling with amino acids in cell culture (SILAC) is the most commonly used approach. SILAC is, however, traditionally limited to simple tissue culture regimens and only ra...

Tunable swelling of polyelectrolyte multilayers in cell culture media for modulating NIH-3T3 cells adhesion.

Science.gov (United States)

Qi, Wei; Cai, Peng; Yuan, Wenjing; Wang, Hua

2014-11-01

For polyelectrolyte multilayers (PEMs) assembled by the layer-by-layer (LbL) assembly technique, their nanostructure and properties can be governed by many parameters during the building process. Here, it was demonstrated that the swelling of the PEMs containing poly(diallyldimethylammonium chloride) (PDDA) and poly(sodium 4-styrenesulfonate) (PSS) in cell culture media could be tuned with changing supporting salt solutions during the assembly process. Importantly, the influence of the PEMs assembled in different salt solutions on NIH-3T3 cell adhesion was observable. Specifically, the cells could possess a higher affinity for the films assembled in low salt concentration (i.e. 0.15M NaCl) or no salt, the poorly swelling films in cell culture media, which was manifested by the large cell spreading area and focal adhesions. In contrast, those were assembled in higher salt concentration, highly swelling films in cell culture media, were less attractive for the fibroblasts. As a result, the cell adhesion behaviors may be manipulated by tailoring the physicochemical properties of the films, which could be performed by changing the assembly conditions such as supporting salt concentration. Such a finding might promise a great potential in designing desired biomaterials for tissue engineering and regenerative medicine. © 2014 Wiley Periodicals, Inc.

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

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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

Micropatterned co-culture of hepatocyte spheroids layered on non-parenchymal cells to understand heterotypic cellular interactions

International Nuclear Information System (INIS)

Otsuka, Hidenori; Sasaki, Kohei; Okimura, Saya; Nagamura, Masako; Nakasone, Yuichi

2013-01-01

Microfabrication and micropatterning techniques in tissue engineering offer great potential for creating and controlling cellular microenvironments including cell–matrix interactions, soluble stimuli and cell–cell interactions. Here, we present a novel approach to generate layered patterning of hepatocyte spheroids on micropatterned non-parenchymal feeder cells using microfabricated poly(ethylene glycol) (PEG) hydrogels. Micropatterned PEG-hydrogel-treated substrates with two-dimensional arrays of gelatin circular domains (ϕ = 100 μm) were prepared by photolithographic method. Only on the critical structure of PEG hydrogel with perfect protein rejection, hepatocytes were co-cultured with non-parenchymal cells to be led to enhanced hepatocyte functions. Then, we investigated the mechanism of the functional enhancement in co-culture with respect to the contributions of soluble factors and direct cell–cell interactions. In particular, to elucidate the influence of soluble factors on hepatocyte function, hepatocyte spheroids underlaid with fibroblasts (NIH/3T3 mouse fibroblasts) or endothelial cells (BAECs: bovine aortic endothelial cells) were compared with physically separated co-culture of hepatocyte monospheroids with NIH3T3 or BAEC using trans-well culture systems. Our results suggested that direct heterotypic cell-to-cell contact and soluble factors, both of these between hepatocytes and fibroblasts, significantly enhanced hepatocyte functions. In contrast, direct heterotypic cell-to-cell contact between hepatocytes and endothelial cells only contributed to enhance hepatocyte functions. This patterning technique can be a useful experimental tool for applications in basic science, drug screening and tissue engineering, as well as in the design of artificial liver devices. (paper)

Semi-automated relative quantification of cell culture contamination with mycoplasma by Photoshop-based image analysis on immunofluorescence preparations.

Science.gov (United States)

Kumar, Ashok; Yerneni, Lakshmana K

2009-01-01

Mycoplasma contamination in cell culture is a serious setback for the cell-culturist. The experiments undertaken using contaminated cell cultures are known to yield unreliable or false results due to various morphological, biochemical and genetic effects. Earlier surveys revealed incidences of mycoplasma contamination in cell cultures to range from 15 to 80%. Out of a vast array of methods for detecting mycoplasma in cell culture, the cytological methods directly demonstrate the contaminating organism present in association with the cultured cells. In this investigation, we report the adoption of a cytological immunofluorescence assay (IFA), in an attempt to obtain a semi-automated relative quantification of contamination by employing the user-friendly Photoshop-based image analysis. The study performed on 77 cell cultures randomly collected from various laboratories revealed mycoplasma contamination in 18 cell cultures simultaneously by IFA and Hoechst DNA fluorochrome staining methods. It was observed that the Photoshop-based image analysis on IFA stained slides was very valuable as a sensitive tool in providing quantitative assessment on the extent of contamination both per se and in comparison to cellularity of cell cultures. The technique could be useful in estimating the efficacy of anti-mycoplasma agents during decontaminating measures.

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.

Culture conditions have an impact on the maturation of traceable, transplantable mouse embryonic stem cell-derived otic progenitor cells.

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Abboud, Nesrine; Fontbonne, Arnaud; Watabe, Isabelle; Tonetto, Alain; Brezun, Jean Michel; Feron, François; Zine, Azel

2017-09-01

The generation of replacement inner ear hair cells (HCs) remains a challenge and stem cell therapy holds the potential for developing therapeutic solutions to hearing and balance disorders. Recent developments have made significant strides in producing mouse otic progenitors using cell culture techniques to initiate HC differentiation. However, no consensus has been reached as to efficiency and therefore current methods remain unsatisfactory. In order to address these issues, we compare the generation of otic and HC progenitors from embryonic stem (ES) cells in two cell culture systems: suspension vs. adherent conditions. In the present study, an ES cell line derived from an Atoh1-green fluorescent protein (GFP) transgenic mouse was used to track the generation of otic progenitors, initial HCs and to compare these two differentiation systems. We used a two-step short-term differentiation method involving an induction period of 5 days during which ES cells were cultured in the presence of Wnt/transforming growth factor TGF-β inhibitors and insulin-like growth factor IGF-1 to suppress mesoderm and reinforce presumptive ectoderm and otic lineages. The generated embryoid bodies were then differentiated in medium containing basic fibroblast growth factor (bFGF) for an additional 5 days using either suspension or adherent culture methods. Upon completion of differentiation, quantitative polymerase chain reaction analysis and immunostaining monitored the expression of otic/HC progenitor lineage markers. The results indicate that cells differentiated in suspension cultures produced cells expressing otic progenitor/HC markers at a higher efficiency compared with the production of these cell types within adherent cultures. Furthermore, we demonstrated that a fraction of these cells can incorporate into ototoxin-injured mouse postnatal cochlea explants and express MYO7A after transplantation. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons

Identification of Viable Helicobacter pylori in Drinking Water Supplies by Cultural and Molecular Techniques.

Science.gov (United States)

Santiago, Paula; Moreno, Yolanda; Ferrús, M Antonía

2015-08-01

Helicobacter pylori is one of the most common causes of chronic bacterial infection in humans, directly related to peptic ulcer and gastric cancer. It has been suggested that H. pylori can be acquired through different transmission routes, including water. In this study, culture and qPCR were used to detect and identify the presence of H. pylori in drinking water. Furthermore, the combined techniques PMA-qPCR and DVC-FISH were applied for detection of viable cells of H. pylori. Among 24 drinking water samples, 16 samples were positive for the presence of H. pylori, but viable cells were only detected in six samples. Characteristic colonies, covered by a mass of bacterial unspecific growth, were observed on selective agar plates from an only sample, after enrichment. The mixed culture was submitted to DVC-FISH and qPCR analysis, followed by sequencing of the amplicons. Molecular techniques confirmed the growth of H. pylori on the agar plate. Our results demonstrate for the first time that H. pylori can survive and be potentially infective in drinking water, showing that water distribution systems could be a potential route for H. pylori transmission. © 2015 John Wiley & Sons Ltd.

Hetero-cellular prototyping by synchronized multi-material bioprinting for rotary cell culture system.

Science.gov (United States)

Snyder, Jessica; Son, Ae Rin; Hamid, Qudus; Wu, Honglu; Sun, Wei

2016-01-13

Bottom-up tissue engineering requires methodological progress of biofabrication to capture key design facets of anatomical arrangements across micro, meso and macro-scales. The diffusive mass transfer properties necessary to elicit stability and functionality require hetero-typic contact, cell-to-cell signaling and uniform nutrient diffusion. Bioprinting techniques successfully build mathematically defined porous architecture to diminish resistance to mass transfer. Current limitations of bioprinted cell assemblies include poor micro-scale formability of cell-laden soft gels and asymmetrical macro-scale diffusion through 3D volumes. The objective of this work is to engineer a synchronized multi-material bioprinter (SMMB) system which improves the resolution and expands the capability of existing bioprinting systems by packaging multiple cell types in heterotypic arrays prior to deposition. This unit cell approach to arranging multiple cell-laden solutions is integrated with a motion system to print heterogeneous filaments as tissue engineered scaffolds and nanoliter droplets. The set of SMMB process parameters control the geometric arrangement of the combined flow's internal features and constituent material's volume fractions. SMMB printed hepatocyte-endothelial laden 200 nl droplets are cultured in a rotary cell culture system (RCCS) to study the effect of microgravity on an in vitro model of the human hepatic lobule. RCCS conditioning for 48 h increased hepatocyte cytoplasm diameter 2 μm, increased metabolic rate, and decreased drug half-life. SMMB hetero-cellular models present a 10-fold increase in metabolic rate, compared to SMMB mono-culture models. Improved bioprinting resolution due to process control of cell-laden matrix packaging as well as nanoliter droplet printing capability identify SMMB as a viable technique to improve in vitro model efficacy.

Hetero-cellular prototyping by synchronized multi-material bioprinting for rotary cell culture system

International Nuclear Information System (INIS)

Snyder, Jessica; Son, Ae Rin; Hamid, Qudus; Sun, Wei; Wu, Honglu

2016-01-01

Bottom-up tissue engineering requires methodological progress of biofabrication to capture key design facets of anatomical arrangements across micro, meso and macro-scales. The diffusive mass transfer properties necessary to elicit stability and functionality require hetero-typic contact, cell-to-cell signaling and uniform nutrient diffusion. Bioprinting techniques successfully build mathematically defined porous architecture to diminish resistance to mass transfer. Current limitations of bioprinted cell assemblies include poor micro-scale formability of cell-laden soft gels and asymmetrical macro-scale diffusion through 3D volumes. The objective of this work is to engineer a synchronized multi-material bioprinter (SMMB) system which improves the resolution and expands the capability of existing bioprinting systems by packaging multiple cell types in heterotypic arrays prior to deposition. This unit cell approach to arranging multiple cell-laden solutions is integrated with a motion system to print heterogeneous filaments as tissue engineered scaffolds and nanoliter droplets. The set of SMMB process parameters control the geometric arrangement of the combined flow’s internal features and constituent material’s volume fractions. SMMB printed hepatocyte-endothelial laden 200 nl droplets are cultured in a rotary cell culture system (RCCS) to study the effect of microgravity on an in vitro model of the human hepatic lobule. RCCS conditioning for 48 h increased hepatocyte cytoplasm diameter 2 μm, increased metabolic rate, and decreased drug half-life. SMMB hetero-cellular models present a 10-fold increase in metabolic rate, compared to SMMB mono-culture models. Improved bioprinting resolution due to process control of cell-laden matrix packaging as well as nanoliter droplet printing capability identify SMMB as a viable technique to improve in vitro model efficacy. (paper)

Mass spectrometric characterization of elements and molecules in cell cultures and tissues

International Nuclear Information System (INIS)

Arlinghaus, H.F.; Kriegeskotte, C.; Fartmann, M.; Wittig, A.; Sauerwein, W.; Lipinsky, D.

2006-01-01

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) and laser post-ionization secondary neutral mass spectrometry (laser-SNMS) have been used to image and quantify targeted compounds, intrinsic elements and molecules with subcellular resolution in single cells of both cell cultures and tissues. Special preparation procedures for analyzing cell cultures and tissue materials were developed. Cancer cells type MeWo, incubated with boronated compounds, were sandwiched between two substrates, cryofixed, freeze-fractured and freeze-dried. Also, after injection with boronated compounds, different types of mouse tissues were extracted, prepared on a special specimen carrier and plunged with high velocity into LN 2 -cooled propane for cryofixation. After trimming, these tissue blocks were freeze-dried. The measurements of the K/Na ratio demonstrated that for both cell cultures and tissue materials the special preparation techniques used were appropriate for preserving the chemical and structural integrity of the living cell. The boron images show inter- and intracellular boron signals with different intensities. Molecular images show distinct features partly correlated with the cell structure. A comparison between laser-SNMS and ToF-SIMS showed that especially laser-SNMS is particularly well-suited for identifying specific cell structures and imaging ultratrace element concentrations in tissues

Cell culture experiments planned for the space bioreactor

Science.gov (United States)

Morrison, Dennis R.; Cross, John H.

1987-01-01

Culturing of cells in a pilot-scale bioreactor remains to be done in microgravity. An approach is presented based on several studies of cell culture systems. Previous and current cell culture research in microgravity which is specifically directed towards development of a space bioprocess is described. Cell culture experiments planned for a microgravity sciences mission are described in abstract form.

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

Discarded human fetal tissue and cell cultures for transplantation research

International Nuclear Information System (INIS)

Hay, R.J.; Phillips, T.; Thompson, A.; Vilner, L.; Cleland, M.; Tchaw-ren Chen; Zabrenetzky, V.

1999-01-01

A feasibility study has been performed to explore the utility of various tissues from discarded human abortuses for transplantation and related research. Specifically, aborted fetuses plus parental blood samples and all relevant clinical data were obtained through a local hospital complex. Whenever possible, pancreas, skin and skeletal muscle, heart, liver, kidney, cartilage and lung tissues were removed, dissociated and subfractionated for cryopreservation, characterization and cultivation trials in vitro. Existing protocols for these manipulations were compared and improved upon as required. Clonal culture, cell aggregate maintenance techniques and use of feeder cell populations have been utilized where appropriate to develop quantitative comparative data. Histological and biochemical assays were applied both to evaluate separation/cultivation methods and to identify optimal culture conditions for maintaining functional cells. Immunochemical and molecular biological procedures were applied to study expression of Major Histocompatibility Vomplex (MHC) class 1 and 11 molecules on cell lines derived. Tissue and cell culture populations were examined for infections with bacteria, ftingi, mycoplasma, HIV, CMV, hepatitis B and other viruses. Only 1% of the abortuses tested were virally infected. Cytogenetic analyses confin-ned the normal diploid status in the vast majority (>98%) of lines tested. A total of over 250 abortuses have been obtained and processed. Only 25 were found to be contaminated with bacteria or fungi and unsuitable for further cultivation trials. A total of over 200 cell populations were isolated, characterized and cryopreserved for further study. Included were kidney, lung, liver and epidermal epithelia: cartilage-derived cells from the spine and epiphyses plus myogenic myoblasts. Selected lines have been immortalized using HPV I 6E6/E7 sequences. Epithelia from the liver and pancreas and cardiac myocytes were the most problematic in that initial

Application of Hanging Drop Technique for Kidney Tissue Culture.

Science.gov (United States)

Wang, Shaohui; Wang, Ximing; Boone, Jasmine; Wie, Jin; Yip, Kay-Pong; Zhang, Jie; Wang, Lei; Liu, Ruisheng

2017-01-01

The hanging drop technique is a well-established method used in culture of animal tissues. However, this method has not been used in adult kidney tissue culture yet. This study was to explore the feasibility of using this technique for culturing adult kidney cortex to study the time course of RNA viability in the tubules and vasculature, as well as the tissue structural integrity. In each Petri dish with the plate covered with sterile buffer, a section of mouse renal cortex was cultured within a drop of DMEM culture medium on the inner surface of the lip facing downward. The tissue were then harvested at each specific time points for Real-time PCR analysis and histological studies. The results showed that the mRNA level of most Na+ related transporters and cotransporters were stably maintained within 6 hours in culture, and that the mRNA level of most receptors found in the vasculature and glomeruli were stably maintained for up to 9 days in culture. Paraffin sections of the cultured renal cortex indicated that the tubules began to lose tubular integrity after 6 hours, but the glomeruli and vasculatures were still recognizable up to 9 days in culture. We concluded that adult kidney tissue culture by hanging drop method can be used to study gene expressions in vasculature and glomeruli. © 2017 The Author(s). Published by S. Karger AG, Basel.

Application of Hanging Drop Technique for Kidney Tissue Culture

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Shaohui Wang

2017-05-01

Full Text Available Background/Aims: The hanging drop technique is a well-established method used in culture of animal tissues. However, this method has not been used in adult kidney tissue culture yet. This study was to explore the feasibility of using this technique for culturing adult kidney cortex to study the time course of RNA viability in the tubules and vasculature, as well as the tissue structural integrity. Methods: In each Petri dish with the plate covered with sterile buffer, a section of mouse renal cortex was cultured within a drop of DMEM culture medium on the inner surface of the lip facing downward. The tissue were then harvested at each specific time points for Real-time PCR analysis and histological studies. Results: The results showed that the mRNA level of most Na+ related transporters and cotransporters were stably maintained within 6 hours in culture, and that the mRNA level of most receptors found in the vasculature and glomeruli were stably maintained for up to 9 days in culture. Paraffin sections of the cultured renal cortex indicated that the tubules began to lose tubular integrity after 6 hours, but the glomeruli and vasculatures were still recognizable up to 9 days in culture. Conclusions: We concluded that adult kidney tissue culture by hanging drop method can be used to study gene expressions in vasculature and glomeruli.

A microfluidic cell culture array with various oxygen tensions.

Science.gov (United States)

Peng, Chien-Chung; Liao, Wei-Hao; Chen, Ying-Hua; Wu, Chueh-Yu; Tung, Yi-Chung

2013-08-21

Oxygen tension plays an important role in regulating various cellular functions in both normal physiology and disease states. Therefore, drug testing using conventional in vitro cell models under normoxia often possesses limited prediction capability. A traditional method of setting an oxygen tension in a liquid medium is by saturating it with a gas mixture at the desired level of oxygen, which requires bulky gas cylinders, sophisticated control, and tedious interconnections. Moreover, only a single oxygen tension can be tested at the same time. In this paper, we develop a microfluidic cell culture array platform capable of performing cell culture and drug testing under various oxygen tensions simultaneously. The device is fabricated using an elastomeric material, polydimethylsiloxane (PDMS) and the well-developed multi-layer soft lithography (MSL) technique. The prototype device has 4 × 4 wells, arranged in the same dimensions as a conventional 96-well plate, for cell culture. The oxygen tensions are controlled by spatially confined oxygen scavenging chemical reactions underneath the wells using microfluidics. The platform takes advantage of microfluidic phenomena while exhibiting the combinatorial diversities achieved by microarrays. Importantly, the platform is compatible with existing cell incubators and high-throughput instruments (liquid handling systems and plate readers) for cost-effective setup and straightforward operation. Utilizing the developed platform, we successfully perform drug testing using an anti-cancer drug, triapazamine (TPZ), on adenocarcinomic human alveolar basal epithelial cell line (A549) under three oxygen tensions ranging from 1.4% to normoxia. The developed platform is promising to provide a more meaningful in vitro cell model for various biomedical applications while maintaining desired high throughput capabilities.

Single molecule microscopy in 3D cell cultures and tissues.

Science.gov (United States)

Lauer, Florian M; Kaemmerer, Elke; Meckel, Tobias

2014-12-15

From the onset of the first microscopic visualization of single fluorescent molecules in living cells at the beginning of this century, to the present, almost routine application of single molecule microscopy, the method has well-proven its ability to contribute unmatched detailed insight into the heterogeneous and dynamic molecular world life is composed of. Except for investigations on bacteria and yeast, almost the entire story of success is based on studies on adherent mammalian 2D cell cultures. However, despite this continuous progress, the technique was not able to keep pace with the move of the cell biology community to adapt 3D cell culture models for basic research, regenerative medicine, or drug development and screening. In this review, we will summarize the progress, which only recently allowed for the application of single molecule microscopy to 3D cell systems and give an overview of the technical advances that led to it. While initially posing a challenge, we finally conclude that relevant 3D cell models will become an integral part of the on-going success of single molecule microscopy. Copyright © 2014 Elsevier B.V. All rights reserved.

Effect of amniotic fluid on the in vitro culture of human corneal endothelial cells.

Science.gov (United States)

Feizi, Sepehr; Soheili, Zahra-Soheila; Bagheri, Abouzar; Balagholi, Sahar; Mohammadian, Azam; Rezaei-Kanavi, Mozhgan; Ahmadieh, Hamid; Samiei, Shahram; Negahban, Kambiz

2014-05-01

The present study was designed to evaluate the effects of human amniotic fluid (HAF) on the growth of human corneal endothelial cells (HCECs) and to establish an in vitro method for expanding HCECs. HCECs were cultured in DMEM-F12 supplemented with 20% fetal bovine serum (FBS). Confluent monolayer cultures were trypsinized and passaged using either FBS- or HAF-containing media. Cell proliferation and cell death ELISA assays were performed to determine the effect of HAF on cell growth and viability. The identity of the cells cultured in 20% HAF was determined using immunocytochemistry (ICC) and real-time reverse transcription polymerase chain reaction (RT-PCR) techniques to evaluate the expression of factors that are characteristic of HCECs, including Ki-67, Vimentin, Na+/K+-ATPase and ZO-1. HCEC primary cultures were successfully established using 20% HAF-containing medium, and these cultures demonstrated rapid cell proliferation according to the cell proliferation and death ELISA assay results. The ICC and real time RT-PCR results indicated that there was a higher expression of Na+/K+-ATPase and ZO-1 in the 20% HAF cell cultures compared with the control (20% FBS) (P < 0.05). The 20% HAF-containing medium exhibited a greater stimulatory effect on HCEC growth and could represent a potential enriched supplement for HCEC regeneration studies. Copyright © 2014 Elsevier Ltd. All rights reserved.

A combined Bodian-Nissl stain for improved network analysis in neuronal cell culture.

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Hightower, M; Gross, G W

1985-11-01

Bodian and Nissl procedures were combined to stain dissociated mouse spinal cord cells cultured on coverslips. The Bodian technique stains fine neuronal processes in great detail as well as an intracellular fibrillar network concentrated around the nucleus and in proximal neurites. The Nissl stain clearly delimits neuronal cytoplasm in somata and in large dendrites. A combination of these techniques allows the simultaneous depiction of neuronal perikarya and all afferent and efferent processes. Costaining with little background staining by either procedure suggests high specificity for neurons. This procedure could be exploited for routine network analysis of cultured neurons.

High cell density cultures produced by internal retention: application in continuous ethanol fermentation

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Berta Carola Pérez

2004-07-01

Full Text Available Ethanol has provoked great interest due to its potential as an alternative fuel. Nevertheless, fermentation processes must be developed by increasing the low volumetric productivity achieved in conventional cultures (batch or continuous to make this product become economically competitive. This can be achieved by using techniques leading to high cell concentration and reducing inhibition by the end-product. One of the frequently employed methods involves cell recycling. This work thus developed a membrane reactor incorporating a filtration module with 5 u,m stainless steel tubular units inside a 3L stirred jar fermenter for investigating its application in continuous ethanol production. The effects of cell concentration and transmembrane pressure difference on permeate flux were evaluated for testing the filtration module's performance. The internal cell retention system was operated in Saccharomyces cerevisiae continuous culture derived from sucrose, once fermentation conditions had been selected (30 °C, 1.25 -1.75 vvm, pH 4.5. Filter unit permeability was maintained by applying pulses of air. More than 97% of the grown cells were retained in the fermenter, reaching 51 g/L cell concentration and 8.51 g/L.h average ethanol productivity in culture with internal cell retention; this was twice that obtained in a conventional continuous culture. Key words: Membrane reactor, Saccharomyces cerevisiae, alcoholic fermentation, cell recycling.

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.

Data of a fluorescent imaging-based analysis of anti-cancer drug effects on three-dimensional cultures of breast cancer cells

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Junji Itou

2015-12-01

Full Text Available Three-dimensional (3D cell culture is a powerful tool to study cell growth under 3D condition. To perform a simple test for anti-cancer drugs in 3D culture, visualization of non-proliferated cells is required. We propose a fluorescent imaging-based assay to analyze cancer cell proliferation in 3D culture. We used a pulse-labeling technique with a photoconvertible fluorescent protein Kaede to identify non-proliferated cells. This assay allows us to observe change in cell proliferation in 3D culture by simple imaging. Using this assay, we obtained the data of the effects of anti-cancer drugs, 5-fluorouracil and PD0332991 in a breast cancer cell line, MCF-7.

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.

Evaluating the role of low-speed centrifugation towards transfecting human peripheral blood mononuclear cell culture.

Science.gov (United States)

Majumdar, M; Ratho, R; Chawla, Y; Singh, M P

2014-01-01

The conventional method of transfection of suspension cells by chemical has proven to be very difficult. We present a new transfection protocol, wherein, low-speed centrifugation of cell culture plates immediately after adding the lipid: DNA complex significantly enhances the transfection efficiency. Peripheral blood mononuclear cells (PBMCs) were transfected with BLOCK-iT™ Fluorescent Oligo (scrambled siRNA) and lipofectamine complex using conventional and low-speed centrifugation modified transfection protocols. The efficiency of transfection was determined using flowcytometer and cell viability was checked using MTT assay. Incorporation of low-speed centrifugation significantly enhances the transfection efficiency of BLOCK-iT™ in the suspension culture of PBMCs as compared to conventional transfection method (99.8% vs 28.3%; P Centrifugation enhanced transfection (CET) technique is simple, time-saving and novel application without compromising the cell viability in the context of recently popular RNA interference in suspension cultures of PBMCs. This undemanding modification might be applicable to a wide variety of cell lines and solve crucial problem of researchers working with RNA interference in suspension cultures.

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.

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

Process cost and facility considerations in the selection of primary cell culture clarification technology.

Science.gov (United States)

Felo, Michael; Christensen, Brandon; Higgins, John

2013-01-01

The bioreactor volume delineating the selection of primary clarification technology is not always easily defined. Development of a commercial scale process for the manufacture of therapeutic proteins requires scale-up from a few liters to thousands of liters. While the separation techniques used for protein purification are largely conserved across scales, the separation techniques for primary cell culture clarification vary with scale. Process models were developed to compare monoclonal antibody production costs using two cell culture clarification technologies. One process model was created for cell culture clarification by disc stack centrifugation with depth filtration. A second process model was created for clarification by multi-stage depth filtration. Analyses were performed to examine the influence of bioreactor volume, product titer, depth filter capacity, and facility utilization on overall operating costs. At bioreactor volumes 5,000 L, clarification using centrifugation followed by depth filtration offers significant cost savings. For bioreactor volumes of ∼ 2,000 L, clarification costs are similar between depth filtration and centrifugation. At this scale, factors including facility utilization, available capital, ease of process development, implementation timelines, and process performance characterization play an important role in clarification technology selection. In the case study presented, a multi-product facility selected multi-stage depth filtration for cell culture clarification at the 500 and 2,000 L scales of operation. Facility implementation timelines, process development activities, equipment commissioning and validation, scale-up effects, and process robustness are examined. © 2013 American Institute of Chemical Engineers.

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

Mammalian Cell Culture Process for Monoclonal Antibody Production: Nonlinear Modelling and Parameter Estimation

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Dan Selişteanu

2015-01-01

Full Text Available Monoclonal antibodies (mAbs are at present one of the fastest growing products of pharmaceutical industry, with widespread applications in biochemistry, biology, and medicine. The operation of mAbs production processes is predominantly based on empirical knowledge, the improvements being achieved by using trial-and-error experiments and precedent practices. The nonlinearity of these processes and the absence of suitable instrumentation require an enhanced modelling effort and modern kinetic parameter estimation strategies. The present work is dedicated to nonlinear dynamic modelling and parameter estimation for a mammalian cell culture process used for mAb production. By using a dynamical model of such kind of processes, an optimization-based technique for estimation of kinetic parameters in the model of mammalian cell culture process is developed. The estimation is achieved as a result of minimizing an error function by a particle swarm optimization (PSO algorithm. The proposed estimation approach is analyzed in this work by using a particular model of mammalian cell culture, as a case study, but is generic for this class of bioprocesses. The presented case study shows that the proposed parameter estimation technique provides a more accurate simulation of the experimentally observed process behaviour than reported in previous studies.

Microspectroscopic investigation of the membrane clogging during the sterile filtration of the growth media for mammalian cell culture.

Science.gov (United States)

Cao, Xiaolin; Loussaert, James A; Wen, Zai-qing

2016-02-05

Growth media for mammalian cell culture are very complex mixtures of several dozens of ingredients, and thus the preparation of qualified media is critical to viable cell density and final product titers. For liquid media prepared from powdered ingredients, sterile filtration is required prior to use to safeguard the cell culture process. Recently one batch of our prepared media failed to pass through the sterile filtration due to the membrane clogging. In this study, we report the root cause analysis of the failed sterile filtration based on the investigations of both the fouling media and the clogged membranes with multiple microspectroscopic techniques. Cellular particles or fragments were identified in the fouling media and on the surfaces of the clogged membranes, which were presumably introduced to the media from the bacterial contamination. This study demonstrated that microspectroscopic techniques may be used to rapidly identify both microbial particles and inorganic precipitates in the cell culture media. Copyright © 2015 Elsevier B.V. All rights reserved.

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.

Culture technique of rabbit primary epidermal keratinocytes

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Marini M

2012-10-01

Full Text Available The epidermis is the protective covering outer layer of the mammalian skin. The epidermal cells are stratified squamous epithelia which undergo continuous differentiation of loss and replacement of cells. Ninety per cent of epidermal cells consist of keratinocytes that are found in the basal layer of the stratified epithelium called epidermis. Keratinocytes are responsible for forming tight junctions with the nerves of the skin as well as in the process of wound healing. This article highlights the method of isolation and culture of rabbit primary epidermal keratinocytes in vitro. Approximately 2cm x 2cm oval shaped line was drawn on the dorsum of the rabbit to mark the surgical area. Then, the skin was carefully excised using a surgical blade and the target skin specimens harvested from the rabbits were placed in transport medium comprising of Dulbecco’s Modified Eagle Medium (DMEM and 1% of antibiotic-antimycotic solution. The specimens were transferred into a petri dish containing 70% ethanol and washed for 5 min followed by a wash in 1 x Dulbecco’s Phosphate Buffered Saline (DBPS. Then, the skin specimens were placed in DMEM and minced into small pieces using a scalpel. The minced pieces were placed in a centrifuge tube containing 0.6% Dispase and 1% antibiotic-antimycotic solution overnight at 4°C in a horizontal orientation. The epidermis layer (whitish, semi-transparent was separated from the dermis (pink, opaque, gooey with the aid of curved forceps by fixing the dermis with one pair of forceps while detaching the epidermis with the second pair. The cells were cultured at a density of 4 x 104 cells/cm2 in culture flask at 37°C and 5% CO2. The cell morphology of the keratinocytes was analyzed using inverted microscope.

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...

A 3D-printed microbial cell culture platform with in situ PEGDA hydrogel barriers for differential substrate delivery.

Science.gov (United States)

Kadilak, Andrea L; Rehaag, Jessica C; Harrington, Cameron A; Shor, Leslie M

2017-09-01

Additive manufacturing, or 3D-printing techniques have recently begun to enable simpler, faster, and cheaper production of millifluidic devices at resolutions approaching 100-200  μ m. At this resolution, cell culture devices can be constructed that more accurately replicate natural environments compared with conventional culturing techniques. A number of microfluidics researchers have begun incorporating additive manufacturing into their work, using 3D-printed devices in a wide array of chemical, fluidic, and even some biological applications. Here, we describe a 3D-printed cell culture platform and demonstrate its use in culturing Pseudomonas putida KT2440 bacteria for 44 h under a differential substrate gradient. Polyethylene glycol diacrylate (PEGDA) hydrogel barriers are patterned in situ within a 3D-printed channel. Transport of the toluidine blue tracer dye through the hydrogel barriers is characterized. Nutrients and oxygen were delivered to cells in the culture region by diffusion through the PEGDA hydrogel barriers from adjacent media or saline perfusion channels. Expression of green fluorescent protein by P. putida KT2440 enabled real time visualization of cell density within the 3D-printed channel, and demonstrated cells were actively expressing protein over the course of the experiment. Cells were observed clustering near hydrogel barrier boundaries where fresh substrate and oxygen were being delivered via diffusive transport, but cells were unable to penetrate the barrier. The device described here provides a versatile and easy to implement platform for cell culture in readily controlled gradient microenvironments. By adjusting device geometry and hydrogel properties, this platform could be further customized for a wide variety of biological applications.

Evaluating the role of low-speed centrifugation towards transfecting human peripheral blood mononuclear cell culture

Directory of Open Access Journals (Sweden)

M Majumdar

2014-01-01

Full Text Available The conventional method of transfection of suspension cells by chemical has proven to be very difficult. We present a new transfection protocol, wherein, low-speed centrifugation of cell culture plates immediately after adding the lipid: DNA complex significantly enhances the transfection efficiency. Peripheral blood mononuclear cells (PBMCs were transfected with BLOCK-iT™ Fluorescent Oligo (scrambled siRNA and lipofectamine complex using conventional and low-speed centrifugation modified transfection protocols. The efficiency of transfection was determined using flowcytometer and cell viability was checked using MTT assay. Incorporation of low-speed centrifugation significantly enhances the transfection efficiency of BLOCK-iT™ in the suspension culture of PBMCs as compared to conventional transfection method (99.8% vs 28.3%; P < 0.0001, even at a low concentration of 40 picomoles without affecting the cell viability. Centrifugation enhanced transfection (CET technique is simple, time-saving and novel application without compromising the cell viability in the context of recently popular RNA interference in suspension cultures of PBMCs. This undemanding modification might be applicable to a wide variety of cell lines and solve crucial problem of researchers working with RNA interference in suspension cultures.

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.

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.

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.

Propagation of Aquilaria malaccensis seedlings through tissue culture techniques

International Nuclear Information System (INIS)

Salahbiah Abdul Majid; Zaiton Ahmad; Mohd Rafaie Abdul Salam; Nurhayati Irwan; Affrida Abu Hassan; Rusli Ibrahim

2010-01-01

Aquilaria malaccensis or karas is the principal source of gaharu resin, which is used in many cultures for incense, perfumes and traditional medicines. The species is mainly propagated conventionally through seeds, cuttings and graftings. Propagation by seeds is usually a reliable method for other forest species, but for karas, this technique is inadequate to meet the current demand of seedling supplies. This is principally due to its low seed viability, low germination rate, delayed rooting of seedlings, long life-cycle and rare seed production. Tissue culture has several advantages over conventional propagation, especially for obtaining large number of uniform and high-yielding plantlets or clones. This paper presents the current progress on mass-propagation of Aquilaria malaccensis seedlings through tissue culture technique at Nuclear Malaysia. (author)

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.

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

Flow field measurements in the cell culture unit

Science.gov (United States)

Walker, Stephen; Wilder, Mike; Dimanlig, Arsenio; Jagger, Justin; Searby, Nancy

2002-01-01

The cell culture unit (CCU) is being designed to support cell growth for long-duration life science experiments on the International Space Station (ISS). The CCU is a perfused loop system that provides a fluid environment for controlled cell growth experiments within cell specimen chambers (CSCs), and is intended to accommodate diverse cell specimen types. Many of the functional requirements depend on the fluid flow field within the CSC (e.g., feeding and gas management). A design goal of the CCU is to match, within experimental limits, all environmental conditions, other than the effects of gravity on the cells, whether the hardware is in microgravity ( micro g), normal Earth gravity, or up to 2g on the ISS centrifuge. In order to achieve this goal, two steps are being taken. The first step is to characterize the environmental conditions of current 1g cell biology experiments being performed in laboratories using ground-based hardware. The second step is to ensure that the design of the CCU allows the fluid flow conditions found in 1g to be replicated from microgravity up to 2g. The techniques that are being used to take these steps include flow visualization, particle image velocimetry (PIV), and computational fluid dynamics (CFD). Flow visualization using the injection of dye has been used to gain a global perspective of the characteristics of the CSC flow field. To characterize laboratory cell culture conditions, PIV is being used to determine the flow field parameters of cell suspension cultures grown in Erlenmeyer flasks on orbital shakers. These measured parameters will be compared to PIV measurements in the CSCs to ensure that the flow field that cells encounter in CSCs is within the bounds determined for typical laboratory experiments. Using CFD, a detailed simulation is being developed to predict the flow field within the CSC for a wide variety of flow conditions, including microgravity environments. Results from all these measurements and analyses of the

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

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

Science.gov (United States)

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.

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.

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.

Isolation and culture of larval cells from C. elegans.

Directory of Open Access Journals (Sweden)

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.

Stochastic modeling of oligodendrocyte generation in cell culture: model validation with time-lapse data

Directory of Open Access Journals (Sweden)

Noble Mark

2006-05-01

Full Text Available Abstract Background The purpose of this paper is two-fold. The first objective is to validate the assumptions behind a stochastic model developed earlier by these authors to describe oligodendrocyte generation in cell culture. The second is to generate time-lapse data that may help biomathematicians to build stochastic models of cell proliferation and differentiation under other experimental scenarios. Results Using time-lapse video recording it is possible to follow the individual evolutions of different cells within each clone. This experimental technique is very laborious and cannot replace model-based quantitative inference from clonal data. However, it is unrivalled in validating the structure of a stochastic model intended to describe cell proliferation and differentiation at the clonal level. In this paper, such data are reported and analyzed for oligodendrocyte precursor cells cultured in vitro. Conclusion The results strongly support the validity of the most basic assumptions underpinning the previously proposed model of oligodendrocyte development in cell culture. However, there are some discrepancies; the most important is that the contribution of progenitor cell death to cell kinetics in this experimental system has been underestimated.

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

Cell Seeding Densities in Autologous Chondrocyte Implantation Techniques for Cartilage Repair.

Science.gov (United States)

Foldager, Casper Bindzus; Gomoll, Andreas H; Lind, Martin; Spector, Myron

2012-04-01

Cartilage repair techniques have been among the most intensively investigated treatments in orthopedics for the past decade, and several different treatment modalities are currently available. Despite the extensive research effort within this field, the generation of hyaline cartilage remains a considerable challenge. There are many parameters attendant to each of the cartilage repair techniques that can affect the amount and types of reparative tissue generated in the cartilage defect, and some of the most fundamental of these parameters have yet to be fully investigated. For procedures in which in vitro-cultured autologous chondrocytes are implanted under a periosteal or synthetic membrane cover, or seeded onto a porous membrane or scaffold, little is known about how the number of cells affects the clinical outcome. Few published clinical studies address the cell seeding density that was employed. The principal objective of this review is to provide an overview of the cell seeding densities used in cell-based treatments currently available in the clinic for cartilage repair. Select preclinical studies that have informed the use of specific cell seeding densities in the clinic are also discussed.

3D+time acquisitions of 3D cell culture by means of lens-free tomographic microscopy

Science.gov (United States)

Berdeu, Anthony; Laperrousaz, Bastien; Bordy, Thomas; Morales, S.; Gidrol, Xavier; Picollet-D'hahan, Nathalie; Allier, Cédric

2018-02-01

We propose a three-dimensional (3D) imaging platform based on lens-free microscopy to perform multi-angle acquisitions on 3D cell cultures embedded in extracellular matrix (ECM). We developed algorithms based on the Fourier diffraction theorem to perform fully 3D reconstructions of biological samples and we adapted the lens-free microscope to incubator conditions. Here we demonstrate for the first time, 3D+time lens-free acquisitions of 3D cell culture over 8 days directly into the incubator. The 3D reconstructed volume is as large as 5 mm3 and provides a unique way to observe in the same 3D cell culture experiment multiple cell migration strategies. Namely, in a 3D cell culture of prostate epithelial cells embedded within a Matrigel® matrix, we are able to distinguish single cell 'leaders', migration of cell clusters, migration of large aggregates of cells, and also close-gap and large-scale branching. In addition, we observe long-scale 3D deformations of the ECM that modify the geometry of the 3D cell culture. Interestingly, we also observed the opposite, i.e. we found that large aggregates of cells may deform the ECM by generating traction forces over very long distances. In sum we put forward a novel 3D lens-free microscopy tomographic technique to study the single and collective cell migrations, the cell-to-cell interactions and the cell-to-matrix interactions.

An introduction to plant cell culture: the future ahead.

Science.gov (United States)

Loyola-Vargas, Víctor M; Ochoa-Alejo, Neftalí

2012-01-01

Plant cell, tissue, and organ culture (PTC) techniques were developed and established as an experimental necessity for solving important fundamental questions in plant biology, but they currently represent very useful biotechnological tools for a series of important applications such as commercial micropropagation of different plant species, generation of disease-free plant materials, production of haploid and doublehaploid plants, induction of epigenetic or genetic variation for the isolation of variant plants, obtention of novel hybrid plants through the rescue of hybrid embryos or somatic cell fusion from intra- or intergeneric sources, conservation of valuable plant germplasm, and is the keystone for genetic engineering of plants to produce disease and pest resistant varieties, to engineer metabolic pathways with the aim of producing specific secondary metabolites or as an alternative for biopharming. Some other miscellaneous applications involve the utilization of in vitro cultures to test toxic compounds and the possibilities of removing them (bioremediation), interaction of root cultures with nematodes or mycorrhiza, or the use of shoot cultures to maintain plant viruses. With the increased worldwide demand for biofuels, it seems that PTC will certainly be fundamental for engineering different plants species in order to increase the diversity of biofuel options, lower the price marketing, and enhance the production efficiency. Several aspects and applications of PTC such as those mentioned above are the focus of this edition.

Impact of Dissolved Oxygen during UV-Irradiation on the Chemical Composition and Function of CHO Cell Culture Media.

Science.gov (United States)

Meunier, Sarah M; Todorovic, Biljana; Dare, Emma V; Begum, Afroza; Guillemette, Simon; Wenger, Andrew; Saxena, Priyanka; Campbell, J Larry; Sasges, Michael; Aucoin, Marc G

2016-01-01

Ultraviolet (UV) irradiation is advantageous as a sterilization technique in the biopharmaceutical industry since it is capable of targeting non-enveloped viruses that are typically challenging to destroy, as well as smaller viruses that can be difficult to remove via conventional separation techniques. In this work, we investigated the influence of oxygen in the media during UV irradiation and characterized the effect on chemical composition using NMR and LC-MS, as well as the ability of the irradiated media to support cell culture. Chemically defined Chinese hamster ovary cell growth media was irradiated at high fluences in a continuous-flow UV reactor. UV-irradiation caused the depletion of pyridoxamine, pyridoxine, pyruvate, riboflavin, tryptophan, and tyrosine; and accumulation of acetate, formate, kynurenine, lumichrome, and sarcosine. Pyridoxamine was the only compound to undergo complete degradation within the fluences considered; complete depletion of pyridoxamine was observed at 200 mJ/cm2. Although in both oxygen- and nitrogen-saturated media, the cell culture performance was affected at fluences above 200 mJ/cm2, there was less of an impact on cell culture performance in the nitrogen-saturated media. Based on these results, minimization of oxygen in cell culture media prior to UV treatment is recommended to minimize the negative impact on sensitive media.

Determination of the synthesis of uptake of α2-macroglobulin by cultured human glioma cells

International Nuclear Information System (INIS)

Druskova, E.; Bizik, J.; Grofova, M.

1994-01-01

Using immunological techniques, the synthesis of α 2 -macroglobulin was studied in established cell lines derived from human glioblastomas multiform. α 2 -Macroglobulin was detected in cytoplasm and in the culture medium of the analyzed cell lines. Radioimmunoprecipitation, revealed a protein with Mr corresponding to α 2 -macroglobulin in the medium conditioned by U-118MG and U-343MG cells. On the other hand, using immunoblot analysis, α 2 -macroglobulin was detected in all of the analyzed lines. In immunofluorescence test, α 2 -macroglobulin was determined also in all four cell lines, but with different staining pattern. Conditioned culture medium of U-536MG cells with the lowest level of α 2 -macroglobulin exerted the lowest mitogenic activity for human fibroblasts. (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...

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

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.

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.

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

Optimized exosome isolation protocol for cell culture supernatant and human plasma

Directory of Open Access Journals (Sweden)

Richard J. Lobb

2015-07-01

Full Text Available Extracellular vesicles represent a rich source of novel biomarkers in the diagnosis and prognosis of disease. However, there is currently limited information elucidating the most efficient methods for obtaining high yields of pure exosomes, a subset of extracellular vesicles, from cell culture supernatant and complex biological fluids such as plasma. To this end, we comprehensively characterize a variety of exosome isolation protocols for their efficiency, yield and purity of isolated exosomes. Repeated ultracentrifugation steps can reduce the quality of exosome preparations leading to lower exosome yield. We show that concentration of cell culture conditioned media using ultrafiltration devices results in increased vesicle isolation when compared to traditional ultracentrifugation protocols. However, our data on using conditioned media isolated from the Non-Small-Cell Lung Cancer (NSCLC SK-MES-1 cell line demonstrates that the choice of concentrating device can greatly impact the yield of isolated exosomes. We find that centrifuge-based concentrating methods are more appropriate than pressure-driven concentrating devices and allow the rapid isolation of exosomes from both NSCLC cell culture conditioned media and complex biological fluids. In fact to date, no protocol detailing exosome isolation utilizing current commercial methods from both cells and patient samples has been described. Utilizing tunable resistive pulse sensing and protein analysis, we provide a comparative analysis of 4 exosome isolation techniques, indicating their efficacy and preparation purity. Our results demonstrate that current precipitation protocols for the isolation of exosomes from cell culture conditioned media and plasma provide the least pure preparations of exosomes, whereas size exclusion isolation is comparable to density gradient purification of exosomes. We have identified current shortcomings in common extracellular vesicle isolation methods and provide a

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)

Microfluidic synthesis of microfibers for magnetic-responsive controlled drug release and cell culture.

Directory of Open Access Journals (Sweden)

Yung-Sheng Lin

Full Text Available This study demonstrated the fabrication of alginate microfibers using a modular microfluidic system for magnetic-responsive controlled drug release and cell culture. A novel two-dimensional fluid-focusing technique with multi-inlets and junctions was used to spatiotemporally control the continuous laminar flow of alginate solutions. The diameter of the manufactured microfibers, which ranged from 211 µm to 364 µm, could be well controlled by changing the flow rate of the continuous phase. While the model drug, diclofenac, was encapsulated into microfibers, the drug release profile exhibited the characteristic of a proper and steady release. Furthermore, the diclofenac release kinetics from the magnetic iron oxide-loaded microfibers could be controlled externally, allowing for a rapid drug release by applying a magnetic force. In addition, the successful culture of glioblastoma multiforme cells in the microfibers demonstrated a good structural integrity and environment to grow cells that could be applied in drug screening for targeting cancer cells. The proposed microfluidic system has the advantages of ease of fabrication, simplicity, and a fast and low-cost process that is capable of generating functional microfibers with the potential for biomedical applications, such as drug controlled release and cell culture.

Cell cycle analysis of cultured mammalian cells after exposure to 4,5',8-trimethylpsoralen and long-wave ultraviolet light

International Nuclear Information System (INIS)

Cohen, S.R.; Burkholder, D.E.; Varga, J.M.; Carter, D.M.; Bartholomew, J.C.

1981-01-01

Cell cycle analysis was used to study the the effect of 4,5'8-trimethylpsoralen (TMP) and long-wave ultraviolet light (UV-A) on cultured mammalian cells. DNA distribution patterns were measured for murine melanoma cells (a cloned line of Cloudman S91) and a strain of diploid human skin fibroblasts (CRL 1295) using both a microfluorimetry procedure and flow cytometry. The untreated cells and those receiving TMP along and UV-A alone had identical DNA content as assessed at several posttreatment intervals (0-72 hr). The majority of cells in control groups contained a G1 DNA content, whereas exposure to TMP (2 x 10(-7) M) plus UV-A (1 Joule/cm2) led to the accumulation of cells in the G2 phase. These observations were similar for each cell type and both analytical techniques were in excellent agreement. The finding that psoralen plus UV-A induces a phase-specific G2 blockade in cultured cells has important implications for understanding the mechanisms which account for enhanced pigmentation and suppression of cellular proliferation following exposure to these agents in vivo

Optimizing structural and mechanical properties of cryogel scaffolds for use in prostate cancer cell culturing

International Nuclear Information System (INIS)

Cecilia, A.; Baecker, A.; Hamann, E.; Rack, A.; Kamp, T. van de; Gruhl, F.J.; Hofmann, R.; Moosmann, J.; Hahn, S.; Kashef, J.; Bauer, S.; Farago, T.; Helfen, L.

2017-01-01

Prostate cancer (PCa) currently is the second most diagnosed cancer in men and the second most cause of cancer death after lung cancer in Western societies. This sets the necessity of modelling prostatic disorders to optimize a therapy against them. The conventional approach to investigating prostatic diseases is based on two-dimensional (2D) cell culturing. This method, however, does not provide a three-dimensional (3D) environment, therefore impeding a satisfying simulation of the prostate gland in which the PCa cells proliferate. Cryogel scaffolds represent a valid alternative to 2D culturing systems for studying the normal and pathological behavior of the prostate cells thanks to their 3D pore architecture that reflects more closely the physiological environment in which PCa cells develop. In this work the 3D morphology of three potential scaffolds for PCa cell culturing was investigated by means of synchrotron X-ray computed micro tomography (SXCμT) fitting the according requirements of high spatial resolution, 3D imaging capability and low dose requirements very well. In combination with mechanical tests, the results allowed identifying an optimal cryogel architecture, meeting the needs for a well-suited scaffold to be used for 3D PCa cell culture applications. The selected cryogel was then used for culturing prostatic lymph node metastasis (LNCaP) cells and subsequently, the presence of multi-cellular tumor spheroids inside the matrix was demonstrated again by using SXCμT. - Highlights: • Synthesis of cryogel scaffolds for prostate cancer cell culturing. • Study of cryogel morphology by synchrotron X-ray computed micro tomography. • Analysis of cryogel mechanical properties with laboratory techniques. • Culturing of prostate cancer cell in the optimal cryogel composition for 21 days. • 3D visualization of the cells by synchrotron X-ray computed micro tomography.

Optimizing structural and mechanical properties of cryogel scaffolds for use in prostate cancer cell culturing

Energy Technology Data Exchange (ETDEWEB)

Cecilia, A. [Institute for Photon Science and Synchrotron Radiation (IPS), Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany); Baecker, A. [Institute of Microstructure Technology (IMT), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1 Bldg 329, Eggenstein-Leopoldshafen, Karlsruhe D-76344 (Germany); Hamann, E. [Institute for Photon Science and Synchrotron Radiation (IPS), Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany); Rack, A. [European Synchrotron Radiation Facility (ESRF), 6 rue Jules Horowitz, 38000 Grenoble (France); Kamp, T. van de [Laboratory for Applications of Synchrotron Radiation (LAS), Karlsruhe Institute of Technology, 6980, D-76128 Karlsruhe (Germany); Gruhl, F.J. [Institute of Microstructure Technology (IMT), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1 Bldg 329, Eggenstein-Leopoldshafen, Karlsruhe D-76344 (Germany); Hofmann, R. [Institute for Photon Science and Synchrotron Radiation (IPS), Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany); Moosmann, J. [Institute of Materials Research, Helmholtz-Zentrum Geesthacht (HZG), Max-Planck-Str. 1, D-21502 Geesthacht (Germany); Hahn, S.; Kashef, J.; Bauer, S.; Farago, T. [Institute for Photon Science and Synchrotron Radiation (IPS), Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany); Helfen, L. [Institute for Photon Science and Synchrotron Radiation (IPS), Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany); European Synchrotron Radiation Facility (ESRF), 6 rue Jules Horowitz, 38000 Grenoble (France); and others

2017-02-01

Prostate cancer (PCa) currently is the second most diagnosed cancer in men and the second most cause of cancer death after lung cancer in Western societies. This sets the necessity of modelling prostatic disorders to optimize a therapy against them. The conventional approach to investigating prostatic diseases is based on two-dimensional (2D) cell culturing. This method, however, does not provide a three-dimensional (3D) environment, therefore impeding a satisfying simulation of the prostate gland in which the PCa cells proliferate. Cryogel scaffolds represent a valid alternative to 2D culturing systems for studying the normal and pathological behavior of the prostate cells thanks to their 3D pore architecture that reflects more closely the physiological environment in which PCa cells develop. In this work the 3D morphology of three potential scaffolds for PCa cell culturing was investigated by means of synchrotron X-ray computed micro tomography (SXCμT) fitting the according requirements of high spatial resolution, 3D imaging capability and low dose requirements very well. In combination with mechanical tests, the results allowed identifying an optimal cryogel architecture, meeting the needs for a well-suited scaffold to be used for 3D PCa cell culture applications. The selected cryogel was then used for culturing prostatic lymph node metastasis (LNCaP) cells and subsequently, the presence of multi-cellular tumor spheroids inside the matrix was demonstrated again by using SXCμT. - Highlights: • Synthesis of cryogel scaffolds for prostate cancer cell culturing. • Study of cryogel morphology by synchrotron X-ray computed micro tomography. • Analysis of cryogel mechanical properties with laboratory techniques. • Culturing of prostate cancer cell in the optimal cryogel composition for 21 days. • 3D visualization of the cells by synchrotron X-ray computed micro tomography.

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

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.

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

Promotion of Vascular Morphogenesis of Endothelial Cells Co-Cultured with Human Adipose-Derived Mesenchymal Stem Cells Using Polycaprolactone/Gelatin Nanofibrous Scaffolds

Directory of Open Access Journals (Sweden)

Yun-Min Kook

2018-02-01

Full Text Available New blood vessel formation is essential for tissue regeneration to deliver oxygen and nutrients and to maintain tissue metabolism. In the field of tissue engineering, in vitro fabrication of new artificial vessels has been a longstanding challenge. Here we developed a technique to reconstruct a microvascular system using a polycaprolactone (PCL/gelatin nanofibrous structure and a co-culture system. Using a simple electrospinning process, we fabricated three-dimensional mesh scaffolds to support the sprouting of human umbilical vein endothelial cells (HUVECs along the electrospun nanofiber. The co-culture with adipose-derived mesenchymal stem cells (ADSCs supported greater sprouting of endothelial cells (ECs. In a two-dimensional culture system, angiogenic cell assembly produced more effective direct intercellular interactions and paracrine signaling from ADSCs to assist in the vascular formation of ECs, compared to the influence of growth factor. Although vascular endothelial growth factor and sphingosine-1-phosphate were present during the culture period, the presence of ADSCs was the most important factor for the construction of a cell-assembled structure in the two-dimensional culture system. On the contrary, HUVECs co-cultured on PCL/gelatin nanofiber scaffolds produced mature and functional microvessel and luminal structures with a greater expression of vascular markers, including platelet endothelial cell adhesion molecule-1 and podocalyxin. Furthermore, both angiogenic factors and cellular interactions with ADSCs through direct contact and paracrine molecules contributed to the formation of enhanced engineered blood vessel structures. It is expected that the co-culture system of HUVECs and ADSCs on bioengineered PCL/gelatin nanofibrous scaffolds will promote robust and functional microvessel structures and will be valuable for the regeneration of tissue with restored blood vessels.

Morphological analysis of human umbilical vein endothelial cells co-cultured with ovarian cancer cells in 3D: An oncogenic angiogenesis assay.

Directory of Open Access Journals (Sweden)

Xiao Wan

Full Text Available Antiangiogenic therapy for cancer is a strategy targeted at tumour vasculature, often in combination with conventional cytotoxicity treatments. Animal testing is still the most common method used for evaluating the efficacy of new drugs but tissue-engineered in vitro models are becoming more acceptable for replacing and reducing the use of animals in anti-cancer drug screening. In this study, a 3D co-culture model of human endothelial cells and ovarian cancer cells was developed. This model has the potential to mimic the interactions between endothelial cells and ovarian cancer cells. The feasibility of applying this model in drug testing was explored here. The complex morphology of the co-culture system, which features development of both endothelial tubule-like structures and tumour structures, was analysed quantitatively by an image analysis method. The co-culture morphology integrity was maintained for 10 days and the potential of the model for anti-cancer drug testing was evaluated using Paclitaxel and Cisplatin, two common anti-tumour drugs with different mechanisms of action. Both traditional cell viability assays and quantitative morphological analyses were applied in the drug testing. Cisplatin proved a good example showing the advantages of morphological analysis of the co-culture model when compared with mono-culture of endothelial cells, which did not reveal an inhibitory effect of Cisplatin on the tubule-like endothelial structures. Thus, the tubule areas of the co-culture reflected the anti-angiogenesis potential of Cisplatin. In summary, in vitro cancer models can be developed using a tissue engineering approach to more closely mimic the characteristics of tumours in vivo. Combined with the image analysis technique, this developed 3D co-culture angiogenesis model will provide more reproducible and reliably quantified results and reveal further information of the drug's effects on both tumour cell growth and tumour angiogenesis.

A voltage-sensitive dye-based assay for the identification of differentiated neurons derived from embryonic neural stem cell cultures.

Directory of Open Access Journals (Sweden)

Richardson N Leão

Full Text Available BACKGROUND: Pluripotent and multipotent stem cells hold great therapeutical promise for the replacement of degenerated tissue in neurological diseases. To fulfill that promise we have to understand the mechanisms underlying the differentiation of multipotent cells into specific types of neurons. Embryonic stem cell (ESC and embryonic neural stem cell (NSC cultures provide a valuable tool to study the processes of neural differentiation, which can be assessed using immunohistochemistry, gene expression, Ca(2+-imaging or electrophysiology. However, indirect methods such as protein and gene analysis cannot provide direct evidence of neuronal functionality. In contrast, direct methods such as electrophysiological techniques are well suited to produce direct evidence of neural functionality but are limited to the study of a few cells on a culture plate. METHODOLOGY/PRINCIPAL FINDINGS: In this study we describe a novel method for the detection of action potential-capable neurons differentiated from embryonic NSC cultures using fast voltage-sensitive dyes (VSD. We found that the use of extracellularly applied VSD resulted in a more detailed labeling of cellular processes compared to calcium indicators. In addition, VSD changes in fluorescence translated precisely to action potential kinetics as assessed by the injection of simulated slow and fast sodium currents using the dynamic clamp technique. We further demonstrate the use of a finite element model of the NSC culture cover slip for optimizing electrical stimulation parameters. CONCLUSIONS/SIGNIFICANCE: Our method allows for a repeatable fast and accurate stimulation of neurons derived from stem cell cultures to assess their differentiation state, which is capable of monitoring large amounts of cells without harming the overall culture.

Evaluation of urogenital Chlamydia trachomatis infections by cell culture and the polymerase chain reaction using a closed system

DEFF Research Database (Denmark)

Østergaard, Lars; Traulsen, J; Birkelund, Svend

1991-01-01

the two test systems were compared, the overall sensitivity of the polymerase chain reaction was 96% and the specificity 94% when compared to the cell culture technique. By use of a closed system for DNA extraction and sample transfer for the polymerase chain reaction, contamination of the samples......Two hundred and fifty-four specimens from males and females consulting a clinic for sexually transmitted diseases were analyzed for genital Chlamydia trachomatis infection. Each clinical sample was tested by the cell culture technique and the polymerase chain reaction using a closed system. When...... not detect Chlamydia trachomatis after sufficient antibiotic treatment of the chlamydial infections....

Evaluation of urogenital Chlamydia trachomatis infections by cell culture and the polymerase chain reaction using a closed system

DEFF Research Database (Denmark)

Østergaard, Lars; Traulsen, J; Birkelund, Svend

1993-01-01

the two test systems were compared, the overall sensitivity of the polymerase chain reaction was 96% and the specificity 94% when compared to the cell culture technique. By use of a closed system for DNA extraction and sample transfer for the polymerase chain reaction, contamination of the samples......Two hundred and fifty-four specimens from males and females consulting a clinic for sexually transmitted diseases were analyzed for genital Chlamydia trachomatis infection. Each clinical sample was tested by the cell culture technique and the polymerase chain reaction using a closed system. When...... not detect Chlamydia trachomatis after sufficient antibiotic treatment of the chlamydial infections....

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...

Dynamic quantitative analysis of adherent cell cultures by means of lens-free video microscopy

Science.gov (United States)

Allier, C.; Vincent, R.; Navarro, F.; Menneteau, M.; Ghenim, L.; Gidrol, X.; Bordy, T.; Hervé, L.; Cioni, O.; Bardin, S.; Bornens, M.; Usson, Y.; Morales, S.

2018-02-01

We present our implementation of lens-free video microscopy setup for the monitoring of adherent cell cultures. We use a multi-wavelength LED illumination together with a dedicated holographic reconstruction algorithm that allows for an efficient removal of twin images from the reconstructed phase image for densities up to those of confluent cell cultures (>500 cells/mm2). We thereby demonstrate that lens-free video microscopy, with a large field of view ( 30 mm2) can enable us to capture the images of thousands of cells simultaneously and directly inside the incubator. It is then possible to trace and quantify single cells along several cell cycles. We thus prove that lens-free microscopy is a quantitative phase imaging technique enabling estimation of several metrics at the single cell level as a function of time, for example the area, dry mass, maximum thickness, major axis length and aspect ratio of each cell. Combined with cell tracking, it is then possible to extract important parameters such as the initial cell dry mass (just after cell division), the final cell dry mass (just before cell division), the average cell growth rate, and the cell cycle duration. As an example, we discuss the monitoring of a HeLa cell cultures which provided us with a data-set featuring more than 10 000 cell cycle tracks and more than 2x106 cell morphological measurements in a single time-lapse.

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

Science.gov (United States)

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.

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.

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

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.

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.

Bacterial Cellulose Shifts Transcriptome and Proteome of Cultured Endothelial Cells Towards Native Differentiation.

Science.gov (United States)

Feil, Gerhard; Horres, Ralf; Schulte, Julia; Mack, Andreas F; Petzoldt, Svenja; Arnold, Caroline; Meng, Chen; Jost, Lukas; Boxleitner, Jochen; Kiessling-Wolf, Nicole; Serbest, Ender; Helm, Dominic; Kuster, Bernhard; Hartmann, Isabel; Korff, Thomas; Hahne, Hannes

2017-09-01

Preserving the native phenotype of primary cells in vitro is a complex challenge. Recently, hydrogel-based cellular matrices have evolved as alternatives to conventional cell culture techniques. We developed a bacterial cellulose-based aqueous gel-like biomaterial, dubbed Xellulin, which mimics a cellular microenvironment and seems to maintain the native phenotype of cultured and primary cells. When applied to human umbilical vein endothelial cells (HUVEC), it allowed the continuous cultivation of cell monolayers for more than one year without degradation or dedifferentiation. To investigate the impact of Xellulin on the endothelial cell phenotype in detail, we applied quantitative transcriptomics and proteomics and compared the molecular makeup of native HUVEC, HUVEC on collagen-coated Xellulin and collagen-coated cell culture plastic (polystyrene).Statistical analysis of 12,475 transcripts and 7831 proteins unveiled massive quantitative differences of the compared transcriptomes and proteomes. K -means clustering followed by network analysis showed that HUVEC on plastic upregulate transcripts and proteins controlling proliferation, cell cycle and protein biosynthesis. In contrast, HUVEC on Xellulin maintained, by and large, the expression levels of genes supporting their native biological functions and signaling networks such as integrin, receptor tyrosine kinase MAP/ERK and PI3K signaling pathways, while decreasing the expression of proliferation associated proteins. Moreover, CD34-an endothelial cell differentiation marker usually lost early during cell culture - was re-expressed within 2 weeks on Xellulin but not on plastic. And HUVEC on Xellulin showed a significantly stronger functional responsiveness to a prototypic pro-inflammatory stimulus than HUVEC on plastic.Taken together, this is one of the most comprehensive transcriptomic and proteomic studies of native and propagated HUVEC, which underscores the importance of the morphology of the cellular

Tuning differentiation signals for efficient propagation and in vitro validation of rat embryonic stem cell cultures.

Science.gov (United States)

Meek, Stephen; Sutherland, Linda; Burdon, Tom

2015-01-01

The rat is one of the most commonly used laboratory animals in biomedical research and the recent isolation of genuine pluripotent rat embryonic stem (ES) cell lines has provided new opportunities for applying contemporary genetic engineering techniques to the rat and enhancing the use of this rodent in scientific research. Technical refinements that improve the stability of the rat ES cell cultures will undoubtedly further strengthen and broaden the use of these stem cells in biomedical research. Here, we describe a relatively simple and robust protocol that supports the propagation of germ line competent rat ES cells, and outline how tuning stem cell signaling using small molecule inhibitors can be used to both stabilize self-renewal of rat ES cell cultures and aid evaluation of their differentiation potential in vitro.

Synthesis and characterization of biocompatible multicomponent polymer systems as supports for cell cultures

International Nuclear Information System (INIS)

Porjazoska, Aleksandra; Cvetkovska, Maja; Yylmaz, Oksan Karal; Baysal, Kemal; Apohan, Nilhan Kayaman; Baysal, Bahattin M.

2004-01-01

Engineering living tissue for reconstructive surgery requires an appropriate cell source and optimal culture conditions, but also a suitable biodegradable scaffold as the basic elements. On the basis of the well known facts that scaffold chemistry and architecture can influence the fate and function of engrafted cells, a large number of polymers, as cell cultures supports, have been proposed. In this study, we report a synthesis, characterization and cell interactions with the following polymer systems: I. Poly[L- lactic acid / glycolic acid / poly(dimethylsiloxane)], copolymers; II. Poly(DL - lactic acid) / triblock PCL - PDMS - PCL copolymers; III. Blends of poly(DL - lactic - co - glycolic acid) and triblock PCL - PDMS - PCL copolymers. For the cell seeding experiments, Swiss 3T3 and/or L929 mouse fibroblasts were grown in RPMI 1640 and/or DMEM / F12 medium, and placed onto the bio polymer non porous or porous films, prepared using a particulate leaching technique. The amount of cells present on the surfaces of the scaffolds was quantified using a neutral red uptake assay. (Author)

Light and electron microscopic localization of GABAA-receptors on cultured cerebellar granule cells and astrocytes using immunohistochemical techniques

DEFF Research Database (Denmark)

Hansen, Gert Helge; Hösli, E; Belhage, B

1991-01-01

. At the light microscope level specific staining of GABAA-receptors was localized in various types of neurones in explant cultures of rat cerebellum using the indirect peroxidase-antiperoxidase (PAP) technique, whereas no specific staining was found in astrocytes. At the electron microscope level labeling...

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

Study on human chondrocyte culture viability for autologous transplantation in clinical application

Directory of Open Access Journals (Sweden)

Christiane Lombello

2003-06-01

Full Text Available Objective: The limited regenerative capacity of the cartilage tissuemakes the treatment of chondral lesions difficult. The techniquescurrently available to treat cartilage lesions may relieve symptoms,but do not regenerate the injured tissue. Autologous chondrocytetransplantation uses cell biology and cell culture techniques toregenerate the hyaline cartilage. Methods: In this study, we analyzechondrocyte biopsy collection and culture for autologoustransplantation. Ultrastructural analyses of hyaline cartilage biopsieswere performed 0, 6, 24 and 48 hours after collection. The tissue evenafter 48 hours. Eleven cell culture assays were performed to evaluateisolation, viability, morphology, proliferation and absence ofcontaminants. Results: The cell culture techniques used allowedchondrocyte proliferation. Rates on cell viability were maintained abovethe acceptable patterns (above 90. Control of cell culture laboratoryconditions showed absence of contaminants, assuring safety of theprocess. The chondrocytes obtained presented the morphology typicalof cultured cell monolayers. Conclusion: The results indicate viabilityof chondrocyte culture technique for clinical application in autologoustransplantation.

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...

Characterization of a plasminogen activator from human melanoma cells cultured in vitro

International Nuclear Information System (INIS)

Heussen, C.

1982-08-01

This thesis describes the work that have been done on the isolation and characterization of a plasminogen activator, Mel-PA, that is released by human melanoma cells cultured in vitro. This enzyme was compared to the urinary plasminogen activator, urokinase. The human melanoma cell line released large amounts of Mel-PA into the surrounding medium when cultured under serum-free conditions. These cells released only one type of plasminogen activator. A technique was developed in which plasminogen activators were seperated electrophoretically and detected in polyacrylamide gel slabs. Mel-PA was concentrated and partially purified by affinity chromatography on benzamidine-sepharose. A study of the distribution of plasminogen activators in tissues and body fluids showed that all mammals examined had two immunochemically distinct plasminogen activators that corresponded, in their distribution, to the urokinase-like and Mel-PA like enzymes of man. A comparitive study of the kinetic behaviour of Mel-PA and urokinase showed numerous differences between the catalytic activities of these two enzymes

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.

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

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)

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

Science.gov (United States)

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

Analytical techniques applied to study cultural heritage objects

Energy Technology Data Exchange (ETDEWEB)

Rizzutto, M.A.; Curado, J.F.; Bernardes, S.; Campos, P.H.O.V.; Kajiya, E.A.M.; Silva, T.F.; Rodrigues, C.L.; Moro, M.; Tabacniks, M.; Added, N., E-mail: rizzutto@if.usp.br [Universidade de Sao Paulo (USP), SP (Brazil). Instituto de Fisica

2015-07-01

The scientific study of artistic and cultural heritage objects have been routinely performed in Europe and the United States for decades. In Brazil this research area is growing, mainly through the use of physical and chemical characterization methods. Since 2003 the Group of Applied Physics with Particle Accelerators of the Physics Institute of the University of Sao Paulo (GFAA-IF) has been working with various methodologies for material characterization and analysis of cultural objects. Initially using ion beam analysis performed with Particle Induced X-Ray Emission (PIXE), Rutherford Backscattering (RBS) and recently Ion Beam Induced Luminescence (IBIL), for the determination of the elements and chemical compounds in the surface layers. These techniques are widely used in the Laboratory of Materials Analysis with Ion Beams (LAMFI-USP). Recently, the GFAA expanded the studies to other possibilities of analysis enabled by imaging techniques that coupled with elemental and compositional characterization provide a better understanding on the materials and techniques used in the creative process in the manufacture of objects. The imaging analysis, mainly used to examine and document artistic and cultural heritage objects, are performed through images with visible light, infrared reflectography (IR), fluorescence with ultraviolet radiation (UV), tangential light and digital radiography. Expanding more the possibilities of analysis, new capabilities were added using portable equipment such as Energy Dispersive X-Ray Fluorescence (ED-XRF) and Raman Spectroscopy that can be used for analysis 'in situ' at the museums. The results of these analyzes are providing valuable information on the manufacturing process and have provided new information on objects of different University of Sao Paulo museums. Improving the arsenal of cultural heritage analysis it was recently constructed an 3D robotic stage for the precise positioning of samples in the external beam setup

Analytical techniques applied to study cultural heritage objects

International Nuclear Information System (INIS)

Rizzutto, M.A.; Curado, J.F.; Bernardes, S.; Campos, P.H.O.V.; Kajiya, E.A.M.; Silva, T.F.; Rodrigues, C.L.; Moro, M.; Tabacniks, M.; Added, N.

2015-01-01

The scientific study of artistic and cultural heritage objects have been routinely performed in Europe and the United States for decades. In Brazil this research area is growing, mainly through the use of physical and chemical characterization methods. Since 2003 the Group of Applied Physics with Particle Accelerators of the Physics Institute of the University of Sao Paulo (GFAA-IF) has been working with various methodologies for material characterization and analysis of cultural objects. Initially using ion beam analysis performed with Particle Induced X-Ray Emission (PIXE), Rutherford Backscattering (RBS) and recently Ion Beam Induced Luminescence (IBIL), for the determination of the elements and chemical compounds in the surface layers. These techniques are widely used in the Laboratory of Materials Analysis with Ion Beams (LAMFI-USP). Recently, the GFAA expanded the studies to other possibilities of analysis enabled by imaging techniques that coupled with elemental and compositional characterization provide a better understanding on the materials and techniques used in the creative process in the manufacture of objects. The imaging analysis, mainly used to examine and document artistic and cultural heritage objects, are performed through images with visible light, infrared reflectography (IR), fluorescence with ultraviolet radiation (UV), tangential light and digital radiography. Expanding more the possibilities of analysis, new capabilities were added using portable equipment such as Energy Dispersive X-Ray Fluorescence (ED-XRF) and Raman Spectroscopy that can be used for analysis 'in situ' at the museums. The results of these analyzes are providing valuable information on the manufacturing process and have provided new information on objects of different University of Sao Paulo museums. Improving the arsenal of cultural heritage analysis it was recently constructed an 3D robotic stage for the precise positioning of samples in the external beam setup

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

Science.gov (United States)

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

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.

Simplification of Bovine Somatic Cell Nuclear Transfer by Application of a Zona-Free Manipulation Technique

DEFF Research Database (Denmark)

Booth, Paul J; Tan, Shijian; Reipurth, Rikke

2001-01-01

Contemporary nuclear transfer techniques often require the involvement of skilled personnel and extended periods of micromanipulation. Here, we present details of the development of a nuclear transfer technique for somatic cells that is both simpler and faster than traditional methods. The techni......Contemporary nuclear transfer techniques often require the involvement of skilled personnel and extended periods of micromanipulation. Here, we present details of the development of a nuclear transfer technique for somatic cells that is both simpler and faster than traditional methods....... The technique comprises the bisection of zona-free oocytes and the reconstruction of embryos comprising two half cytoplasts and a somatic cell by adherence using phytohaemagglutinin-P (PHA) followed by an electropulse and subsequent culture in microwells (termed WOWs--well of the well). The development......-intact zygotes were not different in either blastocyst yield (44.6 +/- 2.4% versus 51.8 +/- 13.5% [mean +/- SEM]) or quality (126.3 +/- 48.4 versus 119.9 +/- 32.6 total cells), and exposure of zygotes to PHA-P did not reduce blastocyst yields compared to vehicle control (40.8 +/- 11.6% versus 47.1 +/- 20...

A Simple Hydrophilic Treatment of SU-8 Surfaces for Cell Culturing and Cell Patterning

DEFF Research Database (Denmark)

Wang, Zhenyu; Stangegaard, Michael; Dufva, Hans Martin

2005-01-01

SU-8, an epoxy-based photoresist, widely used in constitution different mTAS systems, is incompatible with mammalian cell adhesion and culture in its native form. Here, we demonstrate a simple, cheap and robust two-step method to render a SU-8 surface hydrophilic and compatible with cell culture........ The contact angle of SU-8 surface was significantly reduced from 90° to 25° after the surface modification. The treated SU-8 surfaces provided a cell culture environment that was comparable with cell culture flask surface in terms of generation time and morphology....

CATEGORICAL IMAGE COMPONENTS IN THE FORMING SYSTEM OF A MARKETING TECHNIQUES MANAGER’S IMAGE CULTURE

Directory of Open Access Journals (Sweden)

Anna Borisovna Cherednyakova

2015-08-01

Full Text Available Based on the understanding of the image culture formation of managers of marketing techniques, as a representative of the social and communication interaction of public structures, categorical apparatus of image culture with an emphasis on the etymology of the image, as an integral component of image culture was analyzed. Categorical components of the image are presented from the standpoint of image culture, as personal new formation, an integral part of the professional activity of the marketing techniques manager: object-communicative categorical component, subject-activity categorical component of image, personality-oriented categorical component, value-acmeological categorical component of image.The aim is to identify and justify the image categorical components as a component of image culture of the marketing techniques manager.Method and methodology of work – a general scientific research approach reflecting scientific apparatus of research.Results. Categorical components of the image, as an image culture component of manager of marketing techniques were defined.Practical implication of the results. The theoretical part of «Imageology» course, special course «Image culture of manager of marketing techniques», the theoretical and methodological study and the formation of image culture.

Combined neutron imaging techniques for cultural heritage purpose

International Nuclear Information System (INIS)

Materna, T.

2009-01-01

This article presents the different new neutron techniques developed by the Ancient Charm collaboration to image objects of cultural heritage importance: Prompt-gamma-ray activation imaging (PGAI) coupled to cold/thermal neutron transmission tomography, Neutron Resonance Capture Imaging (NRCI) and Neutron Resonance Tomography.

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...

Establishment of automated culture system for murine induced pluripotent stem cells

Directory of Open Access Journals (Sweden)

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.

Assessment of Culture Condition and In Vitro Colonization Ability of Human Spermatogonial Stem Cells: A Review Article

Directory of Open Access Journals (Sweden)

Maryam Mahal Dashtian

2013-06-01

Full Text Available Spermatogenesis is a highly complex and regulated process in which germ stem cells differentiate into spermatozoa. These stem cells, called spermatogonial stem cells (SSCs, are in the base of seminiferous tubules and have the ability of self-renewal and differentiation into functional germ cells. Due to this ability, SSCs can restore spermatogenesis after testicular damage caused by cytotoxic materials or following transplantation into an infertile recipient. Therefore, self-renewal of these cells is critical for the preservation of SSC populations and restoration of fertility. While previous studies have shown that the SSCs of mice and other species can survive and proliferate for long periods of time, little information is available about suitable culture media for the growth of human SSCs. Identification of SSC markers allows for the isolation of these populations of cells. The isolated cell can be expanded in culture and transplanted into infertile recipients. Consequently, the recognition of markers and the establishment of long-term culture systems for human SSCs will be essential for using the potential of these cells in a clinical setting. In this article, we focus on the markers that have been identified for human SSCs and in vitro culture techniques used for human SSCs proliferation.

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.

Effect of Aflatoxin B1 on Growth of Bovine Mammary Epithelial Cells in 3D and Monolayer Culture System.

Science.gov (United States)

Forouharmehr, Ali; Harkinezhad, Taher; Qasemi-Panahi, Babak

2013-01-01

Many studies have been showed transfer of aflatoxins, toxins produced by Aspergillus flvaus and Aspergillus parasiticus fungi, into milk. These toxins are transferred into the milk through digestive system by eating contaminated food. Due to the toxicity of these materials, it seems that it has side effects on the growth of mammary cells. Therefore, the present work aimed to investigate possible toxic effects of aflatoxin B1 (AFB1) on bovine mammary epithelial cells in monolayer and three-dimensional cultures. Specimens of the mammary tissue of bovine were sized out in size 2×2 cm in slaughterhouse. After disinfection and washing in sterile PBS, primary cell culture was performed by enzymatic digestion of tissue with collagenase. When proper numbers of cells were achieved in monolayer culture, cells were seeded in a 24-well culture plate for three-dimensional (3D) culture in Matrigel matrix. After 21 days of 3D culture and reaching the required number of cells, the concentrations of 15, 25 and 35 µL of AFB1 were added to the culture in quadruplicate and incubated for 8 hours. Cellular cytotoxicity was examined using standard colorimetric assay and finally, any change in the morphology of the cells was studied by microscopic technique. Microscopic investigations showed necrosis of the AFB1-exposed cells compared to the control cells. Also, bovine mammary epithelial cells were significantly affected by AFB1 in dose and time dependent manner in cell viability assays. According to the results, it seems that AFB1 can induce cytotoxicity and necrosis in bovine mammary epithelial cells.

Cell synchrony techniques. I. A comparison of methods

Energy Technology Data Exchange (ETDEWEB)

Grdina, D.J.; Meistrich, M.L.; Meyn, R.E.; Johnson, T.S.; White, R.A.

1984-01-01

Selected cell synchrony techniques, as applied to asynchronous populations of Chinese hamster ovary (CHO) cells, have been compared. Aliquots from the same culture of exponentially growing cells were synchronized using mitotic selection, mitotic selection and hydroxyurea block, centrifugal elutriation, or an EPICS V cell sorter. Sorting of cells was achieved after staining cells with Hoechst 33258. After syncronization by the various methods the relative distribution of cells in G/sub 1/, S, or G/sub 2/ + M phases of the cell cycle was determined by flow cytometry. Fractions of synchronized cells obtained from each method were replated and allowed to progress through a second cell cycle. Mitotic selection gave rise to relatively pure and unperturbed early G/sub 1/ phase cells. While cell synchrony rapidly dispersed with time, cells progressed through the cell cycle in 12 hr. Sorting with the EPIC V on the modal G/sub 1/ peak yielded a relatively pure but heterogeneous G/sub 1/ population (i.e. early to late G/sub 1/). Again, synchrony dispersed with time, but cell-cycle progression required 14 hr. With centrifugal elutriation, several different cell populations synchronized throughout the cell cycle could be rapidly obtained with a purity comparable to mitotic selection and cell sorting. It was concluded that, either alone or in combination with blocking agents such as hydroxyurea, elutriation and mitotic selection were both excellent methods for synchronizing CHO cells. Cell sorting exhibited limitations in sample size and time required for synchronizing CHO cells. Its major advantage would be its ability to isolate cell populations unique with respect to selected cellular parameters. 19 references, 9 figures.

Plant Tissue Culture

Indian Academy of Sciences (India)

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Plant tissue culture is a technique of culturing plant cells, tissues and organs on ... working methods (Box 2) and discovery of the need for B vita- mins and auxins for ... Kotte (Germany) reported some success with growing isolated root tips.

Development of a method for the accurate measurement of protein turnover in neoplastic cells grown in culture

International Nuclear Information System (INIS)

Silverman, J.A.

1984-01-01

In this study, it was shown that standard techniques for cell recovery and sample preparation for liquid scintillation counting led to underestimation of the radioactivity present in cell proteins by 20-40%. These techniques involved labeling with 3 He leucine or 14 C leucine, scraping the cells from the dish in a buffer, TCA precipitation of the cell proteins, solubilization in NaOH and counting in a liquid scintillation counter. Hydrolysis of the proteins with HCl or Pronase significantly increased the recovery of the labeled proteins. Also, solubilization in situ with NaOH or hydrolysis in situ with Pronase recovered 5-10% additional labeled proteins. The techniques developed here allow the accurate measurement of radioactivity in cell proteins. In addition, these techniques were used to study protein turnover in rat hepatoma cells grown in culture. These cells regulated their growth rate through changes in the protein synthesis rate as opposed to changes in the protein degradation rate. These data support the hypothesis that neoplastic cells, unlike normal cells, do not regulate proteolysis in growth control; normal cells under similar conditions have been shown to activate lysosomal proteolysis as they reach confluence. The physiologic implications of this observation are discussed

Insights into Caco-2 cell culture structure using coherent anti-Stokes Raman scattering (CARS) microscopy.

Science.gov (United States)

Saarinen, Jukka; Sözeri, Erkan; Fraser-Miller, Sara J; Peltonen, Leena; Santos, Hélder A; Isomäki, Antti; Strachan, Clare J

2017-05-15

We have used coherent anti-Stokes Raman scattering (CARS) microscopy as a novel and rapid, label-free and non-destructive imaging method to gain structural insights into live intestinal epithelial cell cultures used for drug permeability testing. Specifically we have imaged live Caco-2 cells in (bio)pharmaceutically relevant conditions grown on membrane inserts. Imaging conditions were optimized, including evaluation of suitable membrane materials and media solutions, as well as tolerable laser powers for non-destructive imaging of the live cells. Lipid structures, in particular lipid droplets, were imaged within the cells on the insert membranes. The size of the individual lipid droplets increased substantially over the 21-day culturing period up to approximately 10% of the volume of the cross section of individual cells. Variation in lipid content has important implications for intestinal drug permeation testing during drug development but has received limited attention to date due to a lack of suitable analytical techniques. CARS microscopy was shown to be well suited for such analysis with the potential for in situ imaging of the same individual cell-cultures that are used for permeation studies. Overall, the method may be used to provide important information about cell monolayer structure to better understand drug permeation results. Copyright © 2017 Elsevier B.V. All rights reserved.

Comprehensive analysis of signal transduction in three-dimensional ECM-based tumor cell cultures

Directory of Open Access Journals (Sweden)

Iris Eke

2015-11-01

Full Text Available Analysis of signal transduction and protein phosphorylation is fundamental to understand physiological and pathological cell behavior as well as identification of novel therapeutic targets. Despite the fact that more physiological three-dimensional cell culture assays are increasingly used, particularly proteomics and phosphoproteomics remain challenging due to easy, robust and reproducible sample preparation. Here, we present an easy-to-perform, reliable and time-efficient method for the production of 3D cell lysates without compromising cell adhesion before cell lysis. The samples can be used for Western blotting as well as phosphoproteome array technology. This technique would be of interest for researchers working in all fields of biology and drug development.

The influence of organizational culture on the use of quality techniques and its impact on performance

DEFF Research Database (Denmark)

Gambi, Lillian; Jørgensen, Frances; Boer, Harry

2013-01-01

This report presents the results of a study about the influence of organizational culture on quality techniques and the impact of matching culture and technique to enhance performance. Data were drawn from 250 manufacturing companies in Brazil and Denmark. Profiles were identified according....... 2- Quality techniques contribute to improve performance, provided they are supported by appropriate cultural characteristics. For instance, the use of goal setting, continuous improvement, and failure prevention and control techniques supported by group and developmental cultures contribute...

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.

Electron microscopy using the genetically encoded APEX2 tag in cultured mammalian cells

Science.gov (United States)

Martell, Jeffrey D; Deerinck, Thomas J; Lam, Stephanie S; Ellisman, Mark H; Ting, Alice Y

2018-01-01

Electron microscopy (EM) is the premiere technique for high-resolution imaging of cellular ultrastructure. Unambiguous identification of specific proteins or cellular compartments in electron micrographs, however, remains challenging because of difficulties in delivering electron-dense contrast agents to specific subcellular targets within intact cells. We recently reported enhanced ascorbate peroxidase 2 (APEX2) as a broadly applicable genetic tag that generates EM contrast on a specific protein or subcellular compartment of interest. This protocol provides guidelines for designing and validating APEX2 fusion constructs, along with detailed instructions for cell culture, transfection, fixation, heavy-metal staining, embedding in resin, and EM imaging. Although this protocol focuses on EM in cultured mammalian cells, APEX2 is applicable to many cell types and contexts, including intact tissues and organisms, and is useful for numerous applications beyond EM, including live-cell proteomic mapping. This protocol, which describes procedures for sample preparation from cell monolayers and cell pellets, can be completed in 10 d, including time for APEX2 fusion construct validation, cell growth, and solidification of embedding resins. Notably, the only additional steps required relative to a standard EM sample preparation are cell transfection and a 2- to 45-min staining period with 3,3′-diaminobenzidine (DAB) and hydrogen peroxide (H2O2). PMID:28796234

Nanotechnology, Cell Culture and Tissue Engineering

Directory of Open Access Journals (Sweden)

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

Analysis of culture-dependent versus culture-independent techniques for identification of bacteria in clinically obtained bronchoalveolar lavage fluid.

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Dickson, Robert P; Erb-Downward, John R; Prescott, Hallie C; Martinez, Fernando J; Curtis, Jeffrey L; Lama, Vibha N; Huffnagle, Gary B

2014-10-01

The diagnosis and management of pneumonia are limited by the use of culture-based techniques of microbial identification, which may fail to identify unculturable, fastidious, and metabolically active viable but unculturable bacteria. Novel high-throughput culture-independent techniques hold promise but have not been systematically compared to conventional culture. We analyzed 46 clinically obtained bronchoalveolar lavage (BAL) fluid specimens from symptomatic and asymptomatic lung transplant recipients both by culture (using a clinical microbiology laboratory protocol) and by bacterial 16S rRNA gene pyrosequencing. Bacteria were identified in 44 of 46 (95.7%) BAL fluid specimens by culture-independent sequencing, significantly more than the number of specimens in which bacteria were detected (37 of 46, 80.4%, P ≤ 0.05) or "pathogen" species reported (18 of 46, 39.1%, P ≤ 0.0001) via culture. Identification of bacteria by culture was positively associated with culture-independent indices of infection (total bacterial DNA burden and low bacterial community diversity) (P ≤ 0.01). In BAL fluid specimens with no culture growth, the amount of bacterial DNA was greater than that in reagent and rinse controls, and communities were markedly dominated by select Gammaproteobacteria, notably Escherichia species and Pseudomonas fluorescens. Culture growth above the threshold of 10(4) CFU/ml was correlated with increased bacterial DNA burden (P Microbiology. All Rights Reserved.

Recombinant Protein Production and Insect Cell Culture and Process

Science.gov (United States)

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

Science.gov (United States)

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

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

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

Science.gov (United States)

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.

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

Science.gov (United States)

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.

Distance distribution of bystander effects in alpha-particle irradiated cell populations using a CR-39-based culture dish

International Nuclear Information System (INIS)

Gaillard, S.; Pusset, D.; Toledo, S.M. de; Azzam, E.I.; Fromm, M.

2008-01-01

Propagation of induced biological effects from irradiated to non-irradiated cells is known to occur in cell cultures exposed to low fluences of charged particles. These bystander effects are currently investigated using microbeam or non-microbeam (broad beams) irradiation techniques. Identification of the targeted and non-targeted bystander cells is critical to our understanding of mechanisms underlying such effects. We developed a novel cell culture dish where the base consists of a thin CR-39 sheet grafted on a thin polyethylene terephthalate (PET) foil. The validity of this device in identifying not only irradiated cells, but also the cellular compartment traversed by the particle track is described. We have optimized track etch parameters that do not interfere with measurement of induced biological endpoints under normal incident irradiation. Thus the culture dishes can be used to determine distance distributions for the propagation of induced biological effects from a hit cell to bystander cells. We describe the computer code developed to determine the distance distributions of propagated biological stress responses in normal human fibroblast cells exposed to very low fluences of alpha particles

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

Science.gov (United States)

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

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

Science.gov (United States)

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.

Effect of Aflatoxin B1 on Growth of Bovine Mammary Epithelial Cells in 3D and Monolayer Culture System

Directory of Open Access Journals (Sweden)

Babak Qasemi-Panahi

2013-02-01

Full Text Available Purpose: Many studies have been showed transfer of aflatoxins, toxins produced by Aspergillus flvaus and Aspergillus parasiticus fungi, into milk. These toxins are transferred into the milk through digestive system by eating contaminated food. Due to the toxicity of these materials, it seems that it has side effects on the growth of mammary cells. Therefore, the present work aimed to investigate possible toxic effects of aflatoxin B1 (AFB1 on bovine mammary epithelial cells in monolayer and three-dimensional cultures. Methods: Specimens of the mammary tissue of bovine were sized out in size 2×2 cm in slaughterhouse. After disinfection and washing in sterile PBS, primary cell culture was performed by enzymatic digestion of tissue with collagenase. When proper numbers of cells were achieved in monolayer culture, cells were seeded in a 24-well culture plate for three-dimensional (3D culture in Matrigel matrix. After 21 days of 3D culture and reaching the required number of cells, the concentrations of 15, 25 and 35 μL of AFB1 were added to the culture in quadruplicate and incubated for 8 hours. Cellular cytotoxicity was examined using standard colorimetric assay and finally, any change in the morphology of the cells was studied by microscopic technique. Results: Microscopic investigations showed necrosis of the AFB1-exposed cells compared to the control cells. Also, bovine mammary epithelial cells were significantly affected by AFB1 in dose and time dependent manner in cell viability assays. Conclusion: According to the results, it seems that AFB1 can induce cytotoxicity and necrosis in bovine mammary epithelial cells.

Thioredoxin (Trxo1) interacts with proliferating cell nuclear antigen (PCNA) and its overexpression affects the growth of tobacco cell culture.

Science.gov (United States)

Calderón, Aingeru; Ortiz-Espín, Ana; Iglesias-Fernández, Raquel; Carbonero, Pilar; Pallardó, Federico Vicente; Sevilla, Francisca; Jiménez, Ana

2017-04-01

Thioredoxins (Trxs), key components of cellular redox regulation, act by controlling the redox status of many target proteins, and have been shown to play an essential role in cell survival and growth. The presence of a Trx system in the nucleus has received little attention in plants, and the nuclear targets of plant Trxs have not been conclusively identified. Thus, very little is known about the function of Trxs in this cellular compartment. Previously, we studied the intracellular localization of PsTrxo1 and confirmed its presence in mitochondria and, interestingly, in the nucleus under standard growth conditions. In investigating the nuclear function of PsTrxo1 we identified proliferating cellular nuclear antigen (PCNA) as a PsTrxo1 target by means of affinity chromatography techniques using purified nuclei from pea leaves. Such protein-protein interaction was corroborated by dot-blot and bimolecular fluorescence complementation (BiFC) assays, which showed that both proteins interact in the nucleus. Moreover, PsTrxo1 showed disulfide reductase activity on previously oxidized recombinant PCNA protein. In parallel, we studied the effects of PsTrxo1 overexpression on Tobacco Bright Yellow-2 (TBY-2) cell cultures. Microscopy and flow-cytometry analysis showed that PsTrxo1 overexpression increases the rate of cell proliferation in the transformed lines, with a higher percentage of the S phase of the cell cycle at the beginning of the cell culture (days 1 and 3) and at the G2/M phase after longer times of culture (day 9), coinciding with an upregulation of PCNA protein. Furthermore, in PsTrxo1 overexpressed cells there is a decrease in the total cellular glutathione content but maintained nuclear GSH accumulation, especially at the end of the culture, which is accompanied by a higher mitotic index, unlike non-overexpressing cells. These results suggest that Trxo1 is involved in the cell cycle progression of TBY-2 cultures, possibly through its link with cellular PCNA

Cell-cycle distributions and radiation responses of Chinese hamster cells cultured continuously under hypoxic conditions

International Nuclear Information System (INIS)

Tokita, N.; Carpenter, S.G.; Raju, M.R.

1984-01-01

Cell-cycle distributions were measured by flow cytometry for Chinese hamster (CHO) cells cultured continuously under hypoxic conditions. DNA histograms showed an accumulation of cells in the early S phase followed by a traverse delay through the S phase, and a G 2 block. During hypoxic culturing, cell viability decreased rapidly to less than 0.1% at 120 h. Radiation responses for cells cultured under these conditions showed an extreme radioresistance at 72 h. Results suggest that hypoxia induces a condition similar to cell synchrony which itself changes the radioresistance of hypoxic cells. (author)

Non-invasive and non-destructive measurements of confluence in cultured adherent cell lines.

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Busschots, Steven; O'Toole, Sharon; O'Leary, John J; Stordal, Britta

2015-01-01

Many protocols used for measuring the growth of adherent monolayer cells in vitro are invasive, destructive and do not allow for the continued, undisturbed growth of cells within flasks. Protocols often use indirect methods for measuring proliferation. Microscopy techniques can analyse cell proliferation in a non-invasive or non-destructive manner but often use expensive equipment and software algorithms. In this method images of cells within flasks are captured by photographing under a standard inverted phase contract light microscope using a digital camera with a camera lens adaptor. Images are analysed for confluence using ImageJ freeware resulting in a measure of confluence known as an Area Fraction (AF) output. An example of the AF method in use on OVCAR8 and UPN251 cell lines is included. •Measurements of confluence from growing adherent cell lines in cell culture flasks is obtained in a non-invasive, non-destructive, label-free manner.•The technique is quick, affordable and eliminates sample manipulation.•The technique provides an objective, consistent measure of when cells reach confluence and is highly correlated to manual counting with a haemocytometer. The average correlation co-efficient from a Spearman correlation (n = 3) was 0.99 ± 0.008 for OVCAR8 (p = 0.01) and 0.99 ± 0.01 for UPN251 (p = 0.01) cell lines.

Engineering systems for the generation of patterned co-cultures for controlling cell-cell interactions.

Science.gov (United States)

Kaji, Hirokazu; Camci-Unal, Gulden; Langer, Robert; Khademhosseini, Ali

2011-03-01

Inside the body, cells lie in direct contact or in close proximity to other cell types in a tightly controlled architecture that often regulates the resulting tissue function. Therefore, tissue engineering constructs that aim to reproduce the architecture and the geometry of tissues will benefit from methods of controlling cell-cell interactions with microscale resolution. We discuss the use of microfabrication technologies for generating patterned co-cultures. In addition, we categorize patterned co-culture systems by cell type and discuss the implications of regulating cell-cell interactions in the resulting biological function of the tissues. Patterned co-cultures are a useful tool for fabricating tissue engineered constructs and for studying cell-cell interactions in vitro, because they can be used to control the degree of homotypic and heterotypic cell-cell contact. In addition, this approach can be manipulated to elucidate important factors involved in cell-matrix interactions. Patterned co-culture strategies hold significant potential to develop biomimetic structures for tissue engineering. It is expected that they would create opportunities to develop artificial tissues in the future. This article is part of a Special Issue entitled Nanotechnologies - Emerging Applications in Biomedicine. 2010 Elsevier B.V. All rights reserved.

Morphological and Immunohistochemical Characterization of Canine Osteosarcoma Spheroid Cell Cultures.

Science.gov (United States)

Gebhard, C; Gabriel, C; Walter, I

2016-06-01

Spheroid cell culture emerges as powerful in vitro tool for experimental tumour research. In this study, we established a scaffold-free three-dimensional spheroid system built from canine osteosarcoma (OS) cells (D17). Spheroids (7, 14 and 19 days of cultivation) and monolayer cultures (2 and 7 days of cultivation) were evaluated and compared on light and electron microscopy. Monolayer and spheroid cultures were tested for vimentin, cytokeratin, alkaline phosphatase, osteocalcin and collagen I by means of immunohistochemistry. The spheroid cell culture exhibited a distinct network of collagen I in particular after 19-day cultivation, whereas in monolayer cultures, collagen I was arranged as a lamellar basal structure. Necrotic centres of large spheroids, as observed in 14- and 19-day cultures, were characterized by significant amounts of osteocalcin. Proliferative activity as determined by Ki-67 immunoreactivity showed an even distribution in two-dimensional cultures. In spheroids, proliferation was predominating in the peripheral areas. Metastasis-associated markers ezrin and S100A4 were shown to be continuously expressed in monolayer and spheroid cultures. We conclude that the scaffold-free spheroid system from canine OS cells has the ability to mimic the architecture of the in vivo tumour, in particular cell-cell and cell-matrix interactions. © 2015 The Authors. Anatomia, Histologia, Embryologia Published by Blackwell Verlag GmbH.

Quantitative volumetric Raman imaging of three dimensional cell cultures

KAUST Repository

Kallepitis, Charalambos

2017-03-22

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.

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

T cell resistance to activation by dendritic cells requires long-term culture in simulated microgravity

Science.gov (United States)

Bradley, Jillian H.; Stein, Rachel; Randolph, Brad; Molina, Emily; Arnold, Jennifer P.; Gregg, Randal K.

2017-11-01

Immune impairment mediated by microgravity threatens the success of space exploration requiring long-duration spaceflight. The cells of most concern, T lymphocytes, coordinate the host response against microbial and cancerous challenges leading to elimination and long-term protection. T cells are activated upon recognition of specific microbial peptides bound on the surface of antigen presenting cells, such as dendritic cells (DC). Subsequently, this engagement results in T cell proliferation and differentiation into effector T cells driven by autocrine interleukin-2 (IL-2) and other cytokines. Finally, the effector T cells acquire the weaponry needed to destroy microbial invaders and tumors. Studies conducted on T cells during spaceflight, or using Earth-based culture systems, have shown reduced production of cytokines, proliferation and effector functions as compared to controls. This may account for the cases of viral reactivation events and opportunistic infections associated with astronauts of numerous missions. This work has largely been based upon the outcome of T cell activation by stimulatory factors that target select T cell signaling pathways rather than the complex, signaling events related to the natural process of antigen presentation by DC. This study tested the response of an ovalbumin peptide-specific T cell line, OT-II TCH, to activation by DC when the T cells were cultured 24-120 h in a simulated microgravity (SMG) environment generated by a rotary cell culture system. Following 72 h culture of T cells in SMG (SMG-T) or control static (Static-T) conditions, IL-2 production by the T cells was reduced in SMG-T cells compared to Static-T cells upon stimulation by phorbol 12-myristate 13-acetate (PMA) and ionomycin. However, when the SMG-T cells were stimulated with DC and peptide, IL-2 was significantly increased compared to Static-T cells. Such enhanced IL-2 production by SMG-T cells peaked at 72 h SMG culture time and decreased thereafter. When

Cell-Detection Technique for Automated Patch Clamping

Science.gov (United States)

McDowell, Mark; Gray, Elizabeth

2008-01-01

A unique and customizable machinevision and image-data-processing technique has been developed for use in automated identification of cells that are optimal for patch clamping. [Patch clamping (in which patch electrodes are pressed against cell membranes) is an electrophysiological technique widely applied for the study of ion channels, and of membrane proteins that regulate the flow of ions across the membranes. Patch clamping is used in many biological research fields such as neurobiology, pharmacology, and molecular biology.] While there exist several hardware techniques for automated patch clamping of cells, very few of those techniques incorporate machine vision for locating cells that are ideal subjects for patch clamping. In contrast, the present technique is embodied in a machine-vision algorithm that, in practical application, enables the user to identify good and bad cells for patch clamping in an image captured by a charge-coupled-device (CCD) camera attached to a microscope, within a processing time of one second. Hence, the present technique can save time, thereby increasing efficiency and reducing cost. The present technique involves the utilization of cell-feature metrics to accurately make decisions on the degree to which individual cells are "good" or "bad" candidates for patch clamping. These metrics include position coordinates (x,y) in the image plane, major-axis length, minor-axis length, area, elongation, roundness, smoothness, angle of orientation, and degree of inclusion in the field of view. The present technique does not require any special hardware beyond commercially available, off-the-shelf patch-clamping hardware: A standard patchclamping microscope system with an attached CCD camera, a personal computer with an imagedata- processing board, and some experience in utilizing imagedata- processing software are all that are needed. A cell image is first captured by the microscope CCD camera and image-data-processing board, then the image

Tumor necrosis factor (cachetin) decreases adipose cell differentiation in primary cell culture

International Nuclear Information System (INIS)

Martin, R.J.; Jones, D.D.; Jewell, D.E.; Hausman, G.J.

1986-01-01

Cachetin has been shown to effect gene product expression in the established adipose cell line 3T3-L1. Expression of messenger RNA for lipoprotein lipase is suppressed in cultured adipocytes. The purpose of this study was to determine the effect of Cachetin on adipose cell differentiation in primary cell culture. Stromalvascular cells obtained from the inguinal fat pad of 4-5 week old Sprague-Dawley rats were grown in culture for two weeks. During the proliferative growth phase all cells were grown on the same medium and labelled with 3 H-thymidine. Cachetin treatment (10 -6 to 10 -10 M) was initiated on day 5, the initial phase of preadipocyte differentiation. Adipocytes and stromal cells were separated using density gradient, and 3 H-thymidine was determined for both cell types. Thymidine incorporation into adipose cells was decreased maximally (∼ 50%) at 10 -10 M. Stromalvascular cells were not influenced at any of the doses tested. Adipose cell lipid content as indicated by oil red-O staining was decreased by Cachetin. Esterase staining by adipose cells treated with Cachetin was increased indicating an increase in intracellular lipase. These studies show that Cachetin has specific effects on primary adipose cell differentiation

Feeding Frequency Affects Cultured Rat Pituitary Cells in Low Gravity

Science.gov (United States)

Hymer, W. C.; Grindeland, R. E.; Salada, T.; Cenci, R.; Krishnan, K.; Mukai, C.; Nagaoka, S.

1996-01-01

In this report, we describe the results of a rat pituitary cell culture experiment done on STS-65 in which the effect of cell feeding on the release of the six anterior pituitary hormones was studied. We found complex microgravity related interactions between the frequency of cell feeding and the quantity and quality (i.e. biological activity) of some of the six hormones released in flight. Analyses of growth hormone (GH) released from cells into culture media on different mission days using gel filtration and ion exchange chromatography yielded qualitatively similar results between ground and flight samples. Lack of cell feeding resulted in extensive cell clumping in flight (but not ground) cultures. Vigorous fibroblast growth occurred in both ground and flight cultures fed 4 times. These results are interpreted within the context of autocrine and or paracrine feedback interactions. Finally the payload specialist successfully prepared a fresh trypsin solution in microgravity, detached the cells from their surface and reinserted them back into the culture chamber. These cells reattached and continued to release hormone in microgravity. In summary, this experiment shows that pituitary cells are microgravity sensitive and that coupled operations routinely associated with laboratory cel1 culture can also be accomplished in low gravity.

Mycoplasma testing of cell substrates and biologics: Review of alternative non-microbiological techniques.

Science.gov (United States)

Volokhov, Dmitriy V; Graham, Laurie J; Brorson, Kurt A; Chizhikov, Vladimir E

2011-01-01

methods for detection of mycoplasmas remains whether these alternative methods can provide a limit of detection comparable or superior to those of the culture methods. An additional challenge is that nucleic acid amplification technique (NAT) methods do not allow for accurate discrimination between viable and non-viable mycoplasma contaminants, which might lead to false-positive results (e.g. from inactivated raw materials, etc.). Our review provides an overview of these alternative methods and discusses the pros and cons of their application for the testing of mycoplasmas in biologics and cell substrates. Published by Elsevier Ltd.

Monitoring programmed cell death of living plant tissues in microfluidics using electrochemical and optical techniques

DEFF Research Database (Denmark)

Mark, Christina; Zor, Kinga; Heiskanen, Arto

such as redox activity, O2 and H2O2 concentration, pH, cell viability and release of target enzymes such as α-amylase. We have optimised an intracellular, whole-cell redox activity assay[3] that detects changes in redox activity in barley aleurone layer during PCD. The assay uses a double mediator......This project focuses on developing and applying a tissue culture system with electrochemical and optical detection techniques for tissue culture of barley aleurone layer to increase understanding of the underlying mechanisms of programmed cell death (PCD) in plants. The major advantage......-system to electrochemically measure redox activity via changes in the NADP:NADPH ratio. Experiments show that redox activity changes depend on phytohormone activation or inactivation of aleurone layer metabolism and subsequent PCD. We have also successfully detected PCD induced by phytohormones in barley aleurone layer using...

Effect of postmortem sampling technique on the clinical significance of autopsy blood cultures.

Science.gov (United States)

Hove, M; Pencil, S D

1998-02-01

Our objective was to investigate the value of postmortem autopsy blood cultures performed with an iodine-subclavian technique relative to the classical method of atrial heat searing and antemortem blood cultures. The study consisted of a prospective autopsy series with each case serving as its own control relative to subsequent testing, and a retrospective survey of patients coming to autopsy who had both autopsy blood cultures and premortem blood cultures. A busy academic autopsy service (600 cases per year) at University of Texas Medical Branch Hospitals, Galveston, Texas, served as the setting for this work. The incidence of non-clinically relevant (false-positive) culture results were compared using different methods for collecting blood samples in a prospective series of 38 adult autopsy specimens. One hundred eleven adult autopsy specimens in which both postmortem and antemortem blood cultures were obtained were studied retrospectively. For both studies, positive culture results were scored as either clinically relevant or false positives based on analysis of the autopsy findings and the clinical summary. The rate of false-positive culture results obtained by an iodine-subclavian technique from blood drawn soon after death were statistically significantly lower (13%) than using the classical method of obtaining blood through the atrium after heat searing at the time of the autopsy (34%) in the same set of autopsy subjects. When autopsy results were compared with subjects' antemortem blood culture results, there was no significant difference in the rate of non-clinically relevant culture results in a paired retrospective series of antemortem blood cultures and postmortem blood cultures using the iodine-subclavian postmortem method (11.7% v 13.5%). The results indicate that autopsy blood cultures obtained using the iodine-subclavian technique have reliability equivalent to that of antemortem blood cultures.

Direct observation of CD4 T cell morphologies and their cross-sectional traction force derivation on quartz nanopillar substrates using focused ion beam technique

Science.gov (United States)

Kim, Dong-Joo; Kim, Gil-Sung; Hyung, Jung-Hwan; Lee, Won-Yong; Hong, Chang-Hee; Lee, Sang-Kwon

2013-07-01

Direct observations of the primary mouse CD4 T cell morphologies, e.g., cell adhesion and cell spreading by culturing CD4 T cells in a short period of incubation (e.g., 20 min) on streptavidin-functionalized quartz nanopillar arrays (QNPA) using a high-content scanning electron microscopy method were reported. Furthermore, we first demonstrated cross-sectional cell traction force distribution of surface-bound CD4 T cells on QNPA substrates by culturing the cells on top of the QNPA and further analysis in deflection of underlying QNPA via focused ion beam-assisted technique.

Characterization of primary human mammary epithelial cells isolated and propagated by conditional reprogrammed cell culture.

Science.gov (United States)

Jin, Liting; Qu, Ying; Gomez, Liliana J; Chung, Stacey; Han, Bingchen; Gao, Bowen; Yue, Yong; Gong, Yiping; Liu, Xuefeng; Amersi, Farin; Dang, Catherine; Giuliano, Armando E; Cui, Xiaojiang

2018-02-20

Conditional reprogramming methods allow for the inexhaustible in vitro proliferation of primary epithelial cells from human tissue specimens. This methodology has the potential to enhance the utility of primary cell culture as a model for mammary gland research. However, few studies have systematically characterized this method in generating in vitro normal human mammary epithelial cell models. We show that cells derived from fresh normal breast tissues can be propagated and exhibit heterogeneous morphologic features. The cultures are composed of CK18, desmoglein 3, and CK19-positive luminal cells and vimentin, p63, and CK14-positive myoepithelial cells, suggesting the maintenance of in vivo heterogeneity. In addition, the cultures contain subpopulations with different CD49f and EpCAM expression profiles. When grown in 3D conditions, cells self-organize into distinct structures that express either luminal or basal cell markers. Among these structures, CK8-positive cells enclosing a lumen are capable of differentiation into milk-producing cells in the presence of lactogenic stimulus. Furthermore, our short-term cultures retain the expression of ERα, as well as its ability to respond to estrogen stimulation. We have investigated conditionally reprogrammed normal epithelial cells in terms of cell type heterogeneity, cellular marker expression, and structural arrangement in two-dimensional (2D) and three-dimensional (3D) systems. The conditional reprogramming methodology allows generation of a heterogeneous culture from normal human mammary tissue in vitro . We believe that this cell culture model will provide a valuable tool to study mammary cell function and malignant transformation.

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

Science.gov (United States)

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.

Advances in tissue engineering through stem cell-based co-culture.

Science.gov (United States)

Paschos, Nikolaos K; Brown, Wendy E; Eswaramoorthy, Rajalakshmanan; Hu, Jerry C; Athanasiou, Kyriacos A

2015-05-01

Stem cells are the future in tissue engineering and regeneration. In a co-culture, stem cells not only provide a target cell source with multipotent differentiation capacity, but can also act as assisting cells that promote tissue homeostasis, metabolism, growth and repair. Their incorporation into co-culture systems seems to be important in the creation of complex tissues or organs. In this review, critical aspects of stem cell use in co-culture systems are discussed. Direct and indirect co-culture methodologies used in tissue engineering are described, along with various characteristics of cellular interactions in these systems. Direct cell-cell contact, cell-extracellular matrix interaction and signalling via soluble factors are presented. The advantages of stem cell co-culture strategies and their applications in tissue engineering and regenerative medicine are portrayed through specific examples for several tissues, including orthopaedic soft tissues, bone, heart, vasculature, lung, kidney, liver and nerve. A concise review of the progress and the lessons learned are provided, with a focus on recent developments and their implications. It is hoped that knowledge developed from one tissue can be translated to other tissues. Finally, we address challenges in tissue engineering and regenerative medicine that can potentially be overcome via employing strategies for stem cell co-culture use. Copyright © 2014 John Wiley & Sons, Ltd.

Stimulation of DNA synthesis in cultured rat alveolar type II cells

International Nuclear Information System (INIS)

Leslie, C.C.; McCormick-Shannon, K.; Robinson, P.C.; Mason, R.J.

1985-01-01

Restoration of the alveolar epithelium after injury is thought to be dependent on the proliferation of alveolar type II cells. To understand the factors that may be involved in promoting type II cell proliferation in vivo, we determined the effect of potential mitogens and culture substrata on DNA synthesis in rat alveolar type II cells in primary culture. Type II cells cultured in basal medium containing 10% fetal bovine serum (FBS) exhibited essentially no DNA synthesis. Factors that stimulated 3 H-thymidine incorporation included cholera toxin, epidermal growth factor, and rat serum. The greatest degree of stimulation was achieved by plating type II cells on an extracellular matrix prepared from bovine corneal endothelial cells and then by culturing the pneumocytes in medium containing rat serum, cholera toxin, insulin, and epidermal growth factor. Under conditions of stimulation of 3 H-thymidine incorporation there was an increased DNA content per culture dish but no increase in cell number. The ability of various culture conditions to promote DNA synthesis in type II cells was verified by autoradiography. Type II cells were identified by the presence of cytoplasmic inclusions, which were visualized by tannic acid staining before autoradiography. These results demonstrate the importance of soluble factors and culture substratum in stimulating DNA synthesis in rat alveolar type II cells in primary culture

Characterisation of prototype Nurmi cultures using culture-based microbiological techniques and PCR-DGGE.

Science.gov (United States)

Waters, Sinéad M; Murphy, Richard A; Power, Ronan F G

2006-08-01

Undefined Nurmi-type cultures (NTCs) have been used successfully to prevent salmonella colonisation in poultry for decades. Such cultures are derived from the caecal contents of specific-pathogen-free birds and are administered via drinking water or spray application onto eggs in the hatchery. These cultures consist of many non-culturable and obligately anaerobic bacteria. Due to their undefined nature it is difficult to obtain approval from regulatory agencies to use these preparations as direct fed microbials for poultry. In this study, 10 batches of prototype NTCs were produced using an identical protocol over a period of 2 years. Traditional microbiological techniques and a molecular culture-independent methodology, polymerase chain reaction combined with denaturing gradient gel electrophoresis (PCR-DGGE), were applied to characterise these cultures and also to examine if the constituents of the NTCs were identical. Culture-dependent analysis of these cultures included plating on a variety of selective and semi-selective agars, examination of colony morphology, Gram-staining and a series of biochemical tests (API, BioMerieux, France). Two sets of PCR-DGGE studies were performed. These involved the amplification of universal and subsequently lactic acid bacteria (LAB)-specific hypervariable regions of a 16S rRNA gene by PCR. Resultant amplicons were subjected to DGGE. Sequence analysis was performed on subsequent bands present in resultant DGGE profiles using the Basic Local Alignment Search Tool (BLAST). Microbiological culturing techniques tended to isolate common probiotic bacterial species from the genera Lactobacillus, Lactococcus, Bifidobacterium, Enterococcus, Clostridium, Escherichia, Pediococcus and Enterobacterium as well as members of the genera, Actinomyces, Bacteroides, Propionibacterium, Capnocytophaga, Proteus, and Klebsiella. Bacteroides, Enterococcus, Escherichia, Brevibacterium, Klebsiella, Lactobacillus, Clostridium, Bacillus, Eubacterium

Regulation of Axolotl (Ambystoma mexicanum) Limb Blastema Cell Proliferation by Nerves and BMP2 in Organotypic Slice Culture.

Science.gov (United States)

Lehrberg, Jeffrey; Gardiner, David M

2015-01-01

We have modified and optimized the technique of organotypic slice culture in order to study the mechanisms regulating growth and pattern formation in regenerating axolotl limb blastemas. Blastema cells maintain many of the behaviors that are characteristic of blastemas in vivo when cultured as slices in vitro, including rates of proliferation that are comparable to what has been reported in vivo. Because the blastema slices can be cultured in basal medium without fetal bovine serum, it was possible to test the response of blastema cells to signaling molecules present in serum, as well as those produced by nerves. We also were able to investigate the response of blastema cells to experimentally regulated changes in BMP signaling. Blastema cells responded to all of these signals by increasing the rate of proliferation and the level of expression of the blastema marker gene, Prrx-1. The organotypic slice culture model provides the opportunity to identify and characterize the spatial and temporal co-regulation of pathways in order to induce and enhance a regenerative response.

Regulation of Axolotl (Ambystoma mexicanum Limb Blastema Cell Proliferation by Nerves and BMP2 in Organotypic Slice Culture.

Directory of Open Access Journals (Sweden)

Jeffrey Lehrberg

Full Text Available We have modified and optimized the technique of organotypic slice culture in order to study the mechanisms regulating growth and pattern formation in regenerating axolotl limb blastemas. Blastema cells maintain many of the behaviors that are characteristic of blastemas in vivo when cultured as slices in vitro, including rates of proliferation that are comparable to what has been reported in vivo. Because the blastema slices can be cultured in basal medium without fetal bovine serum, it was possible to test the response of blastema cells to signaling molecules present in serum, as well as those produced by nerves. We also were able to investigate the response of blastema cells to experimentally regulated changes in BMP signaling. Blastema cells responded to all of these signals by increasing the rate of proliferation and the level of expression of the blastema marker gene, Prrx-1. The organotypic slice culture model provides the opportunity to identify and characterize the spatial and temporal co-regulation of pathways in order to induce and enhance a regenerative response.

Effectiveness of mesenchymal stems cells cultured by hanging drop vs. conventional culturing on the repair of hypoxic-ischemic-damaged mouse brains, measured by stemness gene expression

OpenAIRE

Lou Yongli; Guo Dewei; Zhang Hui; Song Laijun

2016-01-01

In this study, we investigated the therapeutic effects of Human Mesenchymal Stem Cells (hMSCs) cultured by hanging drop and conventional culturing methods on cerebellar repair in hypoxic-ischemic (HI) brain injured mice. Real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) was used to analyze the expression levels of three stemness genes, Oct4, Sox2 and Nanog, and the migration related gene CXCR4. MSC prepared by hanging drop or conventional techniques were adminis...

EXPLANTATION OF MESANGIAL CELL HILLOCKS - A METHOD FOR OBTAINING HUMAN MESANGIAL CELLS IN CULTURE

NARCIS (Netherlands)

MULLER, EW; KIM, Y; MICHAEL, AF; VERNIER, RL; VANDERHEM, GK; VANDERWOUDE, FJ

A simple method is presented for selective cell culture of human mesangial cells using explanatation of mesangial cell hillocks. Glomeruli which had been incubated with collagenase were explanted on plastic tissue culture flasks. Three to 6 weeks after explantation, a rapidly growing multilayer of

Effects of cell concentrations on the survival and repopulation of haemopoietic stem cells in irradiated bone marrow cell culture in vitro

International Nuclear Information System (INIS)

Fujitake, Hideki; Okamoto, Yuruko; Okubo, Hiroshi; Miyanomae, Takeshi; Kumagai, Keiko; Mori, K.J.

1981-01-01

Effects of cell concentrations on the survival and repopulation of haemopoietic stem cells after irradiation were studied in the long-term culture of mouse bone marrow cells in vitro. No difference was observed in the survival of the stem cells among cultures in which 0 - 10 7 cells were re-inoculated on the adherent cell colonies in the culture flask. Stem cells showed a significant proliferation within 1 week and the number of the stem cells exceeded the control in 3 weeks after irradiation in the cultures with less than 10 6 re-inoculated cells per flask. In contrast, there was a considerable delay in the onset of stem cell proliferation after irradiation in the culture with 10 7 cells per flask. Based on these results, a possibility that a stimulator of stem cell proliferation, released from irradiated stromal cells, is cancelled by an inhibitory factor produced by irradiated or unirradiated haemopoietic cells is postulated. (author)

21 CFR 876.5885 - Tissue culture media for human ex vivo tissue and cell culture processing applications.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Tissue culture media for human ex vivo tissue and cell culture processing applications. 876.5885 Section 876.5885 Food and Drugs FOOD AND DRUG... DEVICES Therapeutic Devices § 876.5885 Tissue culture media for human ex vivo tissue and cell culture...

Retinal pigment epithelium culture;a potential source of retinal stem cells.

Science.gov (United States)

Akrami, Hassan; Soheili, Zahra-Soheila; Khalooghi, Keynoush; Ahmadieh, Hamid; Rezaie-Kanavi, Mojgan; Samiei, Shahram; Davari, Malihe; Ghaderi, Shima; Sanie-Jahromi, Fatemeh

2009-07-01

To establish human retinal pigment epithelial (RPE) cell culture as a source for cell replacement therapy in ocular diseases. Human cadaver globes were used to isolate RPE cells. Each globe was cut into several pieces of a few millimeters in size. After removing the sclera and choroid, remaining tissues were washed in phosphate buffer saline and RPE cells were isolated using dispase enzyme solution and cultured in Dulbecco's Modified Eagle's Medium: Nutrient Mixture F-12 supplemented with 10% fetal calf serum. Primary cultures of RPE cells were established and spheroid colonies related to progenitor/stem cells developed in a number of cultures. The colonies included purely pigmented or mixed pigmented and non-pigmented cells. After multiple cellular passages, several types of photoreceptors and neural-like cells were detected morphologically. Cellular plasticity in RPE cell cultures revealed promising results in terms of generation of stem/progenitor cells from human RPE cells. Whether the spheroids and neural-like retinal cells were directly derived from retinal stem cells or offspring of trans-differentiating or de-differentiating RPE cells remains to be answered.

Enhanced infectivity of bluetongue virus in cell culture by centrifugation.