OBJECTIVE: Conventional methods for organotypic hippocampal tissue slice culture (OHSC) have shown several disadvantages or limitations regarding age of animals used, duration of culture and difficulty using neurodegenerative models. Therefore, we tried to establish OHSC from old 3xTg-Alzheimer’s disease (AD) mice for longer period (over 4 weeks) and to validate utility of this system as a valid platform for translational neuroscience of AD. METHODS: OHSC was performed with old 3xTg-AD mice (12–14 months), old wild type mice (12–14 months) and young 3xTg-AD mice (2–4 months) using serum-free medium for 4 weeks. Hippocampal structure was evaluated by 4’, 6-diamidino-2-phenylindole (DAPI) intensity and neuronal metabolism was measured by Alamarblue assay. Pathologic characteristics of AD were also investigated; β-amyloid levels by ELISA, amyloid plaque deposition by Thioflavin-S staining, and glial activation by immunohistochemistry. RESULTS: Following 4-week culture in serum-free media, hippocampal cells and layers were well preserved in cultured slices from old AD mice as was in those from young AD and old wild type mice. On the contrary, excessive regression of total visible cells was observed in conventional serum-containing medium regardless of genotype of mice. In parallel with this well preserved structure, major pathologic characteristics of AD were also well manifested in hippocampal slices from old AD mice. CONCLUSION: Our findings suggest that long-term OHSC from old 3xTg-AD mouse can serve as a promising ex vivo system for studies on pathophysiology of AD, especially with the minimum number of sacrifice of experimental animals.
Alzheimer Disease ; Animals ; Culture Media, Serum-Free ; Enzyme-Linked Immunosorbent Assay ; Genotype ; Hippocampus ; Immunohistochemistry ; Metabolism ; Mice ; Neurons ; Neurosciences ; Plaque, Amyloid

The toxic effect of ammonia on rCHO-GS cell decreased obviously due to the transfection of GS system in serum-free culture. The maximum cell density, 15.6 x 10(5) cells/mL was obtained in the culture with 1.42 mmol/L ammonia. The growth of rCHO-GS cell was inhibited with an increased ammonia concentration. However, a cell density of 8.9 x 10(5) cells/mL was obtained when the concentration of ammonia was 12.65mmol/L. The intracellar metabolic pathways were affected due to the decrease of the toxic effect of ammonia on rCHO-GS cell. With the increase of initial ammonia concentration from 0.36mmol/L to 12.65mmol/L, the yield coefficients of cell to glucose and lactate to glucose decreased. The activities of hexokinase (HK), pyruvate kinase (PK), and lactate dehydrogenase (LDH) increased by 43%, 140% and 25%, respectively, indicating that the utilization of glucose increased and the glycolysis pathway was more prone to efficient energy metabolism pathway. An increased activity of glutamate-pyruvate aminotransferase (GPT) showed that the conversation from glutamate to alpha-ketoglutarate was shifted to glutamate-pyruvate transamination pathway. The deamination pathway was inhibited due to a decreased activity of glutamate dehydrogenase. In addition, the number of cells in G0/G1 phase increased and the specific production rate of recombinant protein increased by 2.1-fold with the increase of initial ammonia concentration from 0.36mmol/L to 12.65mmol/L.
Ammonia ; metabolism ; toxicity ; Animals ; CHO Cells ; Cell Culture Techniques ; methods ; Cricetinae ; Cricetulus ; Culture Media, Serum-Free ; Genetic Engineering ; methods ; Glutamate-Ammonia Ligase ; genetics ; metabolism ; Glutamine ; metabolism

Taking a suspension adapted recombinant CHO cell line, 11G-S expressing human Pro-urokinase (Pro-UK) as the object of study, the impacts of different feeding nutrients, the start time of feeding and cell inoculation density on the growth and Pro-UK production of 11G-S cells in serum-free fed-batch culture were evaluated in 100 mL shacking flasks. The results indicated that amino acids, serum-free supplements and inorganic salts played important role in cell growth, cell viability and protein expression. And the effects of cells fed-batch culture was much better with the initial cell inoculation density at 3 x 10(5)-4 x 10(5) cells/mL and the start time of feeding set at 72 h, a maximum viable cells density of 7.8 x 10(6) cells/mL with a peak Pro-UK activity at 8570 IU/mL was achieved during 12 d fed-batch culture. Further, the mu of the 11G-S cells at the middle phase of the fed-batch culture, and both the q(glu) and q(gln) of the 11G-S cells at the middle and later phases of the fed-batch culture was higher than that of the 11G-S cells at the same phase of the batch culture, respectively.
Animals ; CHO Cells ; Cell Culture Techniques ; methods ; Cricetinae ; Cricetulus ; Culture Media, Serum-Free ; Humans ; Recombinant Proteins ; biosynthesis ; genetics ; metabolism ; Urokinase-Type Plasminogen Activator ; biosynthesis ; genetics ; metabolism

By using the cell density, cell viability, Pro-UK activity, specific consumption rate of glucose (q(glc)), specific production rate of lactate (q(lac)), yield of lactate to glucose (Y(lac/glc)) and as the evaluation indexes, the growth and metabolism characteristics of pro-urokinase (Pro-UK) expressing CHO cells in serum-free suspension batch culture were examined and compared to those in serum-containing suspension batch culture. We observed hardly differences in growth and metabolism characteristics between the CHO cell populations grown in serum-free suspension batch culture and serum-containing suspension batch culture. The optimal mathematical model parameters for the CHO cells grown in suspension batch culture were obtained by non-linear programming of data representing the growth, substrate consumption and product formation of the CHO cells during logarithmic growth phase using MATLAB software, and the kinetic model of the cell growth and metabolism in serum-free culture were established.
Animals ; Bioreactors ; CHO Cells ; Cricetinae ; Cricetulus ; Culture Media, Serum-Free ; Culture Techniques ; methods ; Kinetics ; Models, Theoretical ; Recombinant Proteins ; biosynthesis ; genetics ; metabolism ; Urokinase-Type Plasminogen Activator ; biosynthesis ; genetics ; metabolism

The presence of serum in a culture medium makes it impossible to identify whether changed cellular functions are directly caused by a manipulation itself or mediated by a component in serum. Madin Darby canine kidney cells can survive in a serum-free medium for about 48 h. We took this advantage to examine whether low K(+)-induced up-regulation of Na,K-ATPase requires serum. We found that serum was essential for low K(+) to induce an increase in Na,K-ATPase binding sites as quantified by ouabain factor binding assays. In an attempt to identify which component was critical, we screened EGF, IGF1, PGE1 and transferrin to identify which one can replace serum. We discovered that transferrin was the single most important factor that mimicked about 80% to 90% of the effect of serum. Transferrin potentiated the effect of low K(+) on the Na,K-ATPase binding sites in a time- and dose-dependent manner. Furthermore, transferrin was also required for low K(+)-induced increase in alpha(1)-promoter activity, alpha(1)- and beta(1)-subunit protein abundance of the Na,K-ATPase. In the presence of transferrin, low K(+) enhanced cellular uptake of iron approximately by 70%. Inhibition of intracellular iron activity by deferoxamine (30 micromol/L) abrogated the effect of low K(+). We conclude that stimulation of the Na,K-ATPase by low K(+) is critically dependent on transferrin. The effect of transferrin is mediated by increased iron transport.
Animals ; Cell Line ; Culture Media, Serum-Free ; Dogs ; Kidney ; cytology ; Potassium ; metabolism ; pharmacology ; Sodium-Potassium-Exchanging ATPase ; genetics ; metabolism ; Transferrin ; metabolism ; pharmacology

AIMTo investigate the influence and mechanisms of 17beta-estradiol on the CTP: phosphorylcholine cytidylyltransferase (CCT) activity from cultured lung explants without serum.

METHODSWe detected the amount of [M-14C] choline incorporation into phosphatidylcholine so as to reflect CCT activity by liquid scintillation.

RESULTS(1) 17beta-estradiol increased the CCT activity in dose-dependence and time-dependence. (2) Both the protein kinase C inhibitor H-7 and calmodulin antagonist W-7 abolished the stimulatory effect of 17beta-estradiol (3 x 10(-6) mol/L) on the CCT activity.

CONCLUSION17beta-estradiol can increase CCT activity in cultured lung explants, its mechanism is related to protein kinase C and calmodulin.

Animals ; Calmodulin ; metabolism ; Choline-Phosphate Cytidylyltransferase ; metabolism ; Culture Media, Serum-Free ; Estradiol ; pharmacology ; In Vitro Techniques ; Lung ; drug effects ; enzymology ; Male ; Protein Kinase C ; metabolism ; Rats ; Rats, Wistar

OBJECTIVETo investigate the expression pattern of CD133 and ALDH1 in colorectal cancer cells line Colo205 cultured in serum-free medium (SFM) containing recombinant human epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF).

METHODSColo205 cells were cultured in serum-free medium (SFM) containing human recombinant EGF and bFGF or in serum-supplemented medium (SSM). The expression of CD133 was analyzed in both groups, and CD133(+) and CD133(-) cells sorted from the SFM group using flow cytometry and observed microscopically for their growth status. The expression of CD133 and ALDH1 in CD133(+) cells and CD133(-) cells was detected by immunofluorescence assay. CD133(+) cells and CD133(-) cells were then injected subcutaneously into NOD/SCID mice and the expression of ALDH1 in the tumor tissues was detected by immunohistochemistry.

RESULTSThe cells in SFM group showed a significantly higher percentage of CD133(+) cells than those in SSM group (P<0.05). In SFM, CD133(+) cells were capable of forming tumor spheres while CD133(-) cells could not; CD133(+)cells strongly expressed CD133 and ALDH1 and CD133(-) cells did not. In mice, tumors generated by CD133(+) cells, but not by CD133(-) cells, positively expressed ALDH1.

CONCLUSIONSCD133(+) Colo205 colorectal cancer cells in SFM containing human recombinant EGF and bFGF can form tumor spheres and strongly express ALDH1. ALDH1 may be one of the candidate markers of colorectal cancer stem cells.

AC133 Antigen ; Animals ; Antigens, CD ; metabolism ; Cell Culture Techniques ; Cell Line, Tumor ; Colorectal Neoplasms ; metabolism ; Culture Media, Serum-Free ; Glycoproteins ; metabolism ; Humans ; Isoenzymes ; metabolism ; Mice ; Mice, Inbred NOD ; Mice, SCID ; Peptides ; metabolism ; Retinal Dehydrogenase ; metabolism

The aim of the present study was to examine the functional changes that occur when a rabbit carotid artery is cultured in serum-free medium. In endothelium (EC)-intact arteries cultured under serum-free conditions, acetylcholine (ACh)-induced relaxation responses were partially, yet significantly, reduced when compared with freshly isolated arteries. After pretreatment with N(G)-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor, application of ACh resulted in a significant contraction in organ cultured arteries. The amplitude of the ACh-induced contractions increased with the duration of culture. In EC-denuded arteries cultured under serum-free conditions, ACh induced responses similar to those in EC-intact arteries pretreated with L-NAME. Furthermore, ACh caused a significant increase in intracellular Ca2+ concentration ([Ca2+]i) in EC-denuded arteries cultured under serum-free condition for 7 days. There was little change in either [Ca2+]i or tension in freshly isolated carotid rings. There was no difference in sodium nitroprusside-induced relaxation responses between fresh and cultured arteries. These results suggest that prolonged culture of carotid arteries under serum-free conditions changes the functional properties of vascular reactivity in rabbit carotid arteries.
Time Factors ; Rabbits ; Organ Culture Techniques/*methods ; Nitroprusside/pharmacology ; NG-Nitroarginine Methyl Ester/metabolism/pharmacology ; *Muscle Contraction ; Models, Statistical ; Dose-Response Relationship, Drug ; Culture Media, Serum-Free/metabolism ; Carotid Arteries/*drug effects/metabolism/*pathology ; Calcium/metabolism ; Animals ; Acetylcholine/*pharmacology

OBJECTIVETo isolate CD133(+) hematopoietic progenitor cells from human umbilical cord blood and optimize the culture condition for maintaining their stem cell characteristics.

METHODSCD133(+) hematopoietic progenitor cells were isolated from human umbilical cord blood using magnetic cell sorting system, and the cells were detected by flow cytometry. Four methods were used for culturing cells. After 8 weeks' culture, cytomorphology, flow cytometry, immunocytochemistry and immunofluorescence assay were used to identify the characteristics of the stem cells.

RESULTSOver 80% of CD133(+) hematopoietic progenitor cells were isolated from human umbilical cord blood using magnetic cell sorting system. The cells were effectively expanded using optimized serum-free medium after 8 weeks of cell culture, whereas the cells in other media differentiated into adherent cells in a poor state.

CONCLUSIONThe optimized serum-free medium allows effective expansion of CD133(+) hematopoietic progenitor cells that maintain stem cell characteristics after a long-term culture.

AC133 Antigen ; Antigens, CD ; metabolism ; Cell Separation ; methods ; Cells, Cultured ; Culture Media, Serum-Free ; Culture Techniques ; methods ; Female ; Fetal Blood ; cytology ; Glycoproteins ; metabolism ; Hematopoietic Stem Cells ; cytology ; Humans ; Infant, Newborn ; Male ; Peptides ; metabolism

Previous studies indicated that B7-H4, the youngest B7 family, negatively regulates T cell-mediated immunity and is significantly overexpressed in many human tumors. Tumor stem cells are purported to play a role in tumor renewal and resistance to radiation and chemotherapy. However, the link between B7-H4 and tumor stem cells is unclear. In this study, we investigated B7-H4 expression in the medium of human glioma U251 cell cultures. Immunofluorescence results showed that U251 cells cultured in serum-free medium (supplemented with 2% B27, 20 ng/mL epidermal growth factor, 20 ng/mL basic fibroblast growth factor) maintained stem-like cell characteristics, including expression of stem cell marker CD133 and the neural progenitor cell markers nestin and SOX2. In contrast, U251 cells cultured in serum-containing medium highly expressed differentiation marker glial fibrillary acidic protein. Flow cytometry analysis showed serum-free medium-cultured U251 cells expressed higher intracellular B7-H4 than serum-containing medium-cultured U251 cells (24%-35% vs. 8%-11%, P < 0.001). Immunofluorescence in purified monocytes from normal human peripheral blood mononuclear cells revealed moderate expression of B7-H4 after stimulation with conditioned medium from U251 cells cultured in serum-containing medium. Moreover, conditioned medium from U251 stem-like cells had a significant stimulation effect on B7-H4 expression compared with serum-containing conditioned medium (P < 0.01). Negative costimulatory molecule B7-H4 was preferentially expressed in U251 stem-like cells, and conditioned medium from these cells more effectively induced monocytes to express B7-H4 than conditioned medium from U251 cells cultured in the presence of serum. Our results show that U251 stem-like cells may play a more crucial role in tumor immunoloregulation with high expression of B7-H4.
AC133 Antigen ; Antigens, CD ; metabolism ; Brain Neoplasms ; metabolism ; pathology ; Cell Line, Tumor ; Cells, Cultured ; Culture Media, Conditioned ; Culture Media, Serum-Free ; Gene Expression Regulation, Neoplastic ; Glial Fibrillary Acidic Protein ; metabolism ; Glioma ; metabolism ; pathology ; Glycoproteins ; metabolism ; Humans ; Monocytes ; cytology ; metabolism ; Neoplastic Stem Cells ; metabolism ; pathology ; Nestin ; metabolism ; Peptides ; metabolism ; SOXB1 Transcription Factors ; metabolism ; V-Set Domain-Containing T-Cell Activation Inhibitor 1 ; metabolism