MACS-W:A modified optical clearing agent for imaging 3D cell cultures

Three-dimensional(3D)cell cultures have contributed to a variety of biological research fields by filling the gap between monolayers and animal models.The modern optical sectioning microscopic methods make it possible to probe the complexity of 3D cell cultures but are limited by the inherent opaqueness.While tissue optical clearing methods have emerged as powerful tools for investigating whole-mount tissues in 3D,they often have limitations,such as being too harsh for fragile 3D cell cultures,requiring complex handling protocols,or inducing tissue deformation with shrinkage or expansion.To address this issue,we proposed a modified optical clearing method for 3D cell cultures,called MACS-W,which is simple,highly efficient,and morphology-preserving.In our evaluation of MACS-W,we found that it exhibits excellent clearing capability in just 10 min,with minimal deformation,and helps drug evaluation on tumor spheroids.In summary,MACS-W is a fast,minimally-deformative and fluorescence compatible clearing method that has the potential to be widely used in the studies of 3D cell cultures.

An Innovative Design of Incubator Structure for Cell Culture

In view of the problems of the traditional cell incubator,such as the small range of cell culture types,the inability to adjust the internal space of the incubator according to needs,and the inconvenient sampling,this study innovatively designed a cell incubator structure.It proposed a new design concept that can solve the above-mentioned shortcomings.The cell incubator after the new structural modification can adjust the internal space structure of cell culture by setting the bolt-fixed connection between the fixed plate and the vessel divider.It realizes the cultivation of various cells through refrigeration modules and heating modules.Through setting a sampling hole in the glass inner door,it is favorable for operators to take samples,making cell culture more convenient and efficient.

Sequential extraction of RNA,DNA and protein from cultured cells of the same group

BACKGROUND Efficient extraction of nucleic acids and proteins(ENAP)from cells is a prerequisite for precise annotation of gene function,and has become laboratory routine for revealing the mysteries of life.However,cell samples are often from different culture dishes,resulting in inevitable experimental errors and sometimes poor repeatability.AIM To explore a method to improve the efficiency of ENAP,minimizing errors in ENAP processes,enhancing the reliability and repeatability of subsequent experimental results.METHODS A protocol for the sequential isolation of RNA,DNA,and proteins from the same cultured HepG2 cells using RNAzol reagent is presented here.The first step involves culturing HepG2 cells to the exponential phase,followed by the sequential isolation of RNA,DNA,and proteins from the same cultured cells in the second step.The yield of nucleic acids and proteins is detected in the third step,and their purity and integrity are verified in the last step.RESULTS The procedure takes as few as 3-4 d from the start to quality verification and is highly efficient.In contrast to the existing kits and reagents,which are primarily based on independent isolation,this RNAzol reagent-based method is characterized by the sequential isolation of RNA,DNA,and proteins from the same cells,and therefore saves time,and has low cost and high efficiency.CONCLUSION The RNA,DNA,and proteins isolated using this method can be used for reverse transcription-polymerase chain reaction,polymerase chain reaction,and western blotting,respectively.

Protective Effects of Quercetin on Cadmium-induced Cytotoxicity in Primary Cultures of Rat Proximal Tubular Cells

Objective To investigate the protective effects of quercetin on cadmium-induced cytotoxicity in primary cultures of rat proximal tubular （rPT） cells. Methods Primary cultures of rPT cells undergoing exponential growth were incubated with 1.0 ug/mL quercetin and/or cadmium （2.5, 5.0 umol/L）, in a serum-free medium at 37℃ at different time intervals. Commercial kits were used and flow cytometric analyses were performed on rPT cell cultures to assay apoptosis and oxidative stress. Results Exposure of rPT cells to cadmium acetate （2.5, 5.0 umol/L） induced a decrease in cell viability, caused an increase in apoptotic rate and apoptotic morphological changes. Simultaneously, elevation of intracellular reactive oxygen species, malondialdehyde and calcium levels, depletion of mitochondrial membrane potential and intracellular glutathione, and inhibition of Na＋, K＋ -ATPase, Ca2＋ -ATPase, glutathione peroxidase （GSH-Px）, catalase （CAT）, and superoxide dismutase （SOD） activities were revealed during the cadmium exposure of rPT cells. However, simultaneous supplementation with 1 ug/mL quercetin protected rPT cells against cadmium-induced cytotoxicity through inhibiting apoptosis, attenuating lipid peroxidation, renewing mitochondrial function and elevating the intracellular antioxidants （non-enzymatic and enzymic） levels. Conclusion The present study has suggested that quercetin, as a widely distributed dietary antioxidant, contributes potentially to prevent cadmium-induced cytotoxicity in rPT cells.

In Vitro Invasive Pattern of Hepatocellular Carcinoma Cell Line HCCLM9 Based on Three-dimensional Cell Culture and Quantum Dots Molecular Imaging

Summary： This study aimed to establish a new in vitro three-dimensional （3D） cell culture and use quantum dots （QDs） molecular imaging to examine the invasive behaviors of hepatocellular carcinoma （HCC） cells. Each well of the 24-well cell culture plate was cover-slipped. Matrigel diluted with se- rum-free DMEM was added and HCCLM9 cells were cultured on the Matrigel. The cell morphological and cell growth characteristics were observed by inverted microscopy and laser confocal microscopy at different culture time. Cell invasive features were monitored by QDs-based real-time molecular imaging techniques. The results showed that on this 3D cell culture platform, HCCLM9 cells exhibited typical multi-step invasive behaviors, including reversion of cell senescence, active focal proliferation and dominant clones invasion. During the process, cells under 3D cell culture showed biological behaviors of spatio-temporal characteristics. Cells first merged on the surface of matrix, then gradually infiltrated and migrated into deep part of matrix, presenting polygonal morphology with stretched protrusions, forming tubular, annular and even network structure, which suggested that HCC cells have the morpho- logical basis for vasculogenic mimicry. In addition, small cell clones with their edges well-circumscribed in early stage, progressed into a large irregular clone with ill-defined edge, while the other cells developed invadopodia. And QDs probing showed MT1-MMP was strongly expressed in the invadopodia. These findings indicate that a novel 3D cell culture platform has been successfully estab- lished, which can mimic the in vivo tumor microenvironment, and when combined with QDs-based mo- lecular imaging, it can help to better investigate the invasive behaviors of HCC cells.

Artificial meat? Feasible approach based on the experience from cell culture studies

This short review is to list pros and cons which are based on the literature and personal experience in cell culture studies related to possible commercial production of artificial meat as functional food. The general view of muscle composition and determinants of meat quality are shortly described. Principles of muscle cell propagation in culture and mutual relationships between different cell types present in this organ are briefly discussed. Additionally, the effects of some cytokines and growth factors for muscle cell growth and muscle tissue development are indicated. Finally, conclusion remarks related to detrimental consequences of meat production to natural environment as well as personal opinion of author on the prospects of artificial meat production are declared.

In vitro Culture of Bone Marrow Mesenchymal Stem Cells in Rats and Differentiation into Retinal Neural-like Cells

In order to study the in vitro culture and expansion of bone marrow mesenchymal stem cells in rats （rMSCs） and the possibility of rMSCs differentiation into retinal neural cells, the bone marrow-derived cells in SD rats were isolated and cultured in vitro. The retinal neural cells in SD rats were cultured and the supernatants were collected to prepare conditioned medium. The cultured rMSCs were induced to differentiate by two steps. Immunofluorescence method and anti-nestin, anti-NeuN, anti-GFAP and anti-Thyl. 1 antibodies were used to identify the cells derived from the rMSCs. The results showed that the in vitro cultured rMSCs grew well and expanded quickly. After induction with two conditioned media, rMSCs was induced to differentiate into neural progenitor cells, then into retinal neural-like cells which were positive for nestin, NeuN, GFAP and Thyl. 1 detected by fluorescence method. The findings suggested that rMSCs could be culture and expanded in vitro, and induced to differentiate into retinal neural-like cells.

Biological Characteristics of Human Bone Marrow Mesenchymal Stem Cell Cultured in Vitro

Some biological characteristics of human bone marrow mesenchymal stem cells (MSCs) cultured in vitro were observed. hMSCs were isolated from bone marrow and purified by density gradient centrifugation method, and then cultured in vitro. The proliferation and growth characteristics of hMSCs were observed in primary and passage culture. MSCs of passage 3 were examined for the purify by positive rate of CD29 and CD44 through flow cytometry. Human bone marrow MSCs showed active proliferation capacity in vitro. The purify of MSCs separated by our method was higher than 90 %. It was concluded that hMSCs have been successfully cultured and expanded effectively. It provided a foundation for further investigation and application of MSCs.

Effect of elicitors, precursors and metabolic inhibitors on paclitaxel production by Taxus cuspidata cell culture

In this study, using Taxus cuspidata as a raw material, we obtained stable high-yielding cell lines by subculturing and quantified paclitaxel content using ultra- sonic extraction combined with TLC-UV spectrophotom- etry. In single factor and multiple factors tests to optimize design and study the effects of elicitors, precursors, and metabolic inhibitors on paclitaxel production by Taxus cuspidata cells, paclitaxel production reached 4.32 mg/L when 100 μmol/L methyl jasmonate, 20 mg/L salicylic acid, 400 mg/L phenylalanine and 2 mg/L gibberellin （GA3） were added to the culture medium of suspension cells. When adding metabolic adjustment factors on the 7th day of culture, extra- and intracellular paclitaxel production was the highest at 4.855 mg/L, paclitaxel release rate was 10.48 %, fresh mass and paclitaxel production of cell increased, respectively, by 6.08 and 11.57 %. By controlling the anabolism of paclitaxel, paclitaxel yield was significantly improved.

Glutathione peroxidase activity in cell cultures from different regions of human epididymis

Aim: To study the secretory activity and androgen regulation of glutathione peroxidase (GPx) in epithelial cell cultures from human epididymis. Methods: Tissue was obtained from patients undergoing therapeutic orchidectomy for prostatic cancer. Epithelial cell cultures were obtained from the caput, corpus and cauda epididymides. Enzymatic activity was measured in conditioned media by colorimetric methods in absence or presence of 1, 10 or 100 nrnoI.L^(-1) testosterone. The effect of 1 μmol.L^(-1) flutamide was also evaluated. Results: GPx activity was higher in cultures from corpus and cauda than caput epididymidis. The presence of different concentrations of testosterone increase enzyme activity in cell cultures from all epididymal regions. Addition of flutamide reverses the androgen dependent increase of GPx activity. Conclusion: GPx activity is secreted from human epididymal cells in a region dependent manner and is regulated by androgens.

Expression of Transforming Growth Factor-β in Cultured Normal Human Lens Epithelia Cells

Summary: In order to investigate whether cultured normal human lens epithelial cells (LEC) express transforming growth factor β (TGF-β), reverse transcriptase polymerase chain reaction (RT-PCR) and immunohistochemical methods were used for detection of TGF-β mRNA and protein in cultured normal human LEC. The results showed that a single RT-PCR amplified product about 310bp was obtained, and the sequence was homologous to the known sequence. TGF-β immunostain was positive in the plasma of LEC. It was suggested that normal human LEC could produce TGF-β, and LEC could be affected by TGF-β through autocrine action.

PRIMARY CELL CULTURE FOR EMBRYONIC CARDIAC MYOCYTES OF MEXICAN AXOLOTL AND DISTRIBUTION OF DESMIN AND VIMENTIN

Desmin and vimentin are major components of intermediate filament proteins in cardiac myocytes. We developed a primary cell culture method for cardiac myocytes of axolotl embryos. Cardiac myocytes of embryonic stage 39 were cultured for 1-14 days. Myocytes showed spontaneous contractions (15-30 beats/min) after 48-72 hours in culture, round shape and large irregular projections. Desmin and vimentin were observed in the cultured myocytes by means of immunofluorescent staining in combination with immunofluorescent microscopy. Immunofluorescent staining of the cultured cardiac myocytes after different lengths of time in culture(3,6,9 days) showed that vimentin staining was stronger than desmin staining during the early stages of culture (3 days). The myocytes exhibited various forms of staining, including parallel lines and interconnected networks. Some lines showed regular striation; most of the myofibrils were arranged in parallel arrays along the cell's long axis. Both desmin and vimentin in the cell appeared to encirele the Z lines and to link myofibrils laterally at the Z lines.

Biotransformation of 14-Deacetoxy-13-oxo sinenxan A by Ginkgo Cell Cultures

Deacetoxy-13-oxo sinenxan A (1) was converted to 9a-hydroxy-13-oxo-2a, 5a, 10b-triacetoxy-4(20),11-taxadiene (2) and 10b-hydroxy-13-oxo-2a,5a,9a-triacetoxy- 4(20), 11- taxadiene (3) by Ginkgo cell suspension cultures in 45% and 15% yields, respectively.

Isolation of Cultured Endothelial Progenitor Cells in vitro from PBMCs and CD133^+ Enriched Cells

Two isolation methods for sorting of endothelial progenitor cells(EPCs):from peripheral blood mononuclear cells(PBMCs)and CD133+ enriched cells were compared,by defining the cell morphology,phenotype,reproductive activities and function in vitro,to provide a reference for clinical application of EPCs.PBMCs from healthy subjects were used either directly for cell culture or for CD133+ sorting.The two groups of cells were cultured in complete medium 199(M199)for 7 to 14 days and the phenotypes of EPCs were an...

Microfabrication of Bubbular Cavities in PDMS for Cell Sorting and Microcell Culture Applications

We describe a novel technique, low surface energy Gas Expansion Molding （GEM）, to fabricate microbubble arrays in polydimethylsiloxane （PDMS） which are incorporated into parallel plate flow chambers and tested in cell sorting and microcell cuTture applications. This architecture confers several operational advantages that distinguish this technology approach from currently used methods. Herein we describe the GEM process and the parameters that are used to control microbubble formation and a Vacuum-Assisted Coating （VAC） process developed to selectively and spatially alter the PDMS surface chemistry in the wells and on the microchannel surface. We describe results from microflow image visualization studies conducted to investigate fluid streams above and within microbubble wells and conclude with a discussion of cell culture studies in PDMS.

Culture conditions for equine bone marrow mesenchymal stem cells and expression of key transcription factors during their differentiation into osteoblasts

Background： The use of equine bone marrow mesenchymal stem cells （BMSC） is a novel method to improve fracture healing in horses. However, additional research is needed to identify optimal culture conditions and to determine the mechanisms involved in regulating BMSC differentiation into osteoblasts. The objectives of the experiments were to determine： 1） if autologous or commercial serum is better for proliferation and differentiation of equine BMSC into osteoblasts, and 2） the expression of key transcription factors during the differentiation of equine BMSC into osteoblasts. Equine BMSC were isolated from the sterna of 3 horses, treated with purchased fetal bovine serum （FBS） or autologous horse serum （HS）, and cell proliferation determined. To induce osteoblast differentiation, cells were incubated with L-ascorbic acid-2-phosphate and glycerol-2-phosphate in the presence or absence of human bone morphogenetic protein2 （BMP2）, dexamethasone （DEX）, or combination of the two. Alkaline phosphatase （ALP） activity, a marker of osteoblast differentiation, was determined by ELISA. Total RNA was isolated from differentiating BMSC between d 0 to 18 to determine expression of runt-reloted tronscrJption foctor2 （Runx2）, osterix （Osx）, and T-box3 （Tbx3）. Data were analyzed by ANOVA. Results： Relative to control, FBS and HS increased cell number （133 ± 5 and 116 ± 5%, respectively; P 〈 0.001） and 5-bromo- 2＇-deoxyuridine （BrdU） incorporation （167 ± 6 and 120 ± 6%, respectively; P 〈 0.001）. Treatment with DEX increased ALP activity compared with control （1,638 ± 38%; P 〈 0.001）. In the absence and presence of Dex, BMP-2 did not alter ALP activity （P 〉 0.8）. Runt-reloted transcription foctor2 expression increased 3-fold （P 〈 0.001） by d 6 of culture. Osterix expression increased 94old （P 〈 0.05） by d 18 of culture. Expression of Tbx3 increased 1.8-fold at d 3 （P 〈 0.01）; however expression was reduced 4-fold at d 18 （P 〈 0.01）. Conclusions： Dexamethasone, but not BMP-2, is required for differentiation of equine BMSC into osteoblasts. In addition, expression of Runx2 and osterix increased and expression of Tbx3 is reduced during differentiation.

ERK phosphorylation functions in invadopodia formation in tongue cancer cells in a novel silicate fibre-based 3D cell culture system

To screen for additional treatment targets against tongue cancer, we evaluated the contributions of extracellular signal-related kinase(ERK), AKT and ezrin in cancer development. Immunohistochemical staining showed that ERK and ezrin expressions were significantly higher in invasive squamous cell carcinoma than in carcinoma in situ. To investigate the roles of ERK and ezrin in cancer development, we used the non-woven silica fibre sheet Cellbedwith a structure resembling the loose connective tissue morphology in a novel 3 D culture system. We confirmed that the 3 D system using CellbedTMaccurately mimicked cancer cell morphology in vivo. Furthermore, cell projections were much more apparent in 3 D-cultured tongue cancer cell lines than in 2 D cultures. Typically, under conventional 2 D culture conditions, F-actin and cortactin are colocalized in the form of puncta within cells.However, in the 3 D-cultured cells, colocalization was mainly observed at the cell margins, including the projections. Projections containing F-actin and cortactin colocalization were predicted to be invadopodia. Although suppressing ezrin expression with small interfering RNA transfection caused no marked changes in morphology, cell projection formation was decreased, and the tumour thickness in vertical sections after 3 D culture was markedly decreased after suppressing ERK activity because both the invasion ability and proliferation were inhibited. An association between cortactin activation as well as ERK activity and invadopodia formation was detected. Our novel 3 D culture systems using Cellbed? are simple and useful for in vitro studies before conducting animal experiments. ERK contributes to tongue cancer development by increasing both cancer cell proliferation and migration via cortactin activation.

Differences in the primary culture, purification and biological characteristics between endothelial cells and smooth muscle cells from rat aorta

Objective： To investigate the differences of primary culture, purification and biological characteristics between endothelial cells and smooth muscle cells from rat aorta. Methods： Endothelial cells were obtained using the vascular ring adherence, collagenase digestion method and an improved vascular ring adherence method, while smooth muscle cells were separated from tissue sections of rat aorta. Clones of endothelial cells were selected by limiting dilution assay. Both cell types were identified using specific cell immunofluorescent markers, and phase contrast microscopy was used to observe the morphological disparity between endothelial cells and smooth muscle cells at the single cell and colony level. Cell proliferation was determined by the cell counting kit-8. Differences between endothelial cells and smooth muscle cells were evaluated in trypsin digestion time, attachment time and recovery after cryopreservation. Results： Endothelial cells were obtained by all three methods. The improved vascular ring method provided the most reproducible results. Cells were in good condition, and of high purity. Smooth muscle cells were cultured successfully by the tissue fragment culture method. Clonal expansion of single endothelial cells was attained. The two cell types expressed their respective specific markers, and the rate of proliferation of smooth muscle cells exceeded that of endothelial cells. Endothelial cells were more sensitive to trypsin digestion than smooth muscle cells. In addition, they had a shorter adherence time and better recovery following cryopreservation than smooth muscle cells. Conclusion： The improved vascular ring method was optimal for yielding endothelial cells. Limiting dilution is a novel and valid method for purifying primary endothelial cells from rat aorta. Primary rat endothelial cell and vascular smooth muscle cell cultures exhibited different morphological characteristics, proliferation rate, adherence time, susceptibility to trypsin digestion and recovery after cryopreservation. Our research can be a good foundation for further application in the regeneration of blood vessel.

Bis(7)-Tacrine, a Promising Anti-Alzheimer's Agent,Attenuates Glutamate-Induced Cell Injury in Primary Cultured Cerebrocortical Neurons of Rats

The effects of bis(7) tacrine, a novel dimeric acetylcholinesterase (AChE) inhibitor, on glutamate induced cell injury were investigated in primary cerebral cortical neurons of rats. Exposure of cultured neurons (12 days after plating) to 0.5 mmol/L glutamate for 30 min resulted in significant cell damage. Pretreatment with bis(7) tacrine (0.03 1.0 μmol/L) reduced the glutamate induced neurotoxicity in a concentration dependent manner and the maximal response was seen at 1 μmol/L with approximately 30% protection. A receptor binding assay showed that bis(7) tacrine can completely displace MK 801 binding to rat cortical membrane with an IC 50 of 0.57 μmol/L. These findings suggest that bis(7) tacrine can directly interact with N methyl D aspartate receptor channel complex, which may contribute to the inhibitor's protective effects against glutamate induced excitotoxicity. Thus, it is possible that anti glutamate/anti AChE synergism is responsible for potentially better Alzheimer's therapy of bis(7) tacrine relative to tacrine.

Cell culture isolation can miss the laboratory diagnosis of HSV ocular infection

AIMWe compared polymerase chain reaction (PCR) to cell culture isolation for the laboratory diagnosis of ocular herpes simplex virus (HSV) disease.