44 research outputs found
Correction of the auditory phenotype in C57BL/6N mice via CRISPR/Cas9-mediated homology directed repair
Violent aggression predicted by multiple pre-adult environmental hits
Early exposure to negative environmental impact shapes individual behavior and potentially contributes to any mental disease. We reported previously that accumulated environmental risk markedly decreases age at schizophrenia onset. Follow-up of matched extreme group individuals (≤1 vs. ≥3 risks) unexpectedly revealed that high-risk subjects had >5 times greater probability of forensic hospitalization. In line with longstanding sociological theories, we hypothesized that risk accumulation before adulthood induces violent aggression and criminal conduct, independent of mental illness. We determined in 6 independent cohorts (4 schizophrenia and 2 general population samples) pre-adult risk exposure, comprising urbanicity, migration, physical and sexual abuse as primary, and cannabis or alcohol as secondary hits. All single hits by themselves were marginally associated with higher violent aggression. Most strikingly, however, their accumulation strongly predicted violent aggression (odds ratio 10.5). An epigenome-wide association scan to detect differential methylation of blood-derived DNA of selected extreme group individuals yielded overall negative results. Conversely, determination in peripheral blood mononuclear cells of histone-deacetylase1 mRNA as 'umbrella mediator' of epigenetic processes revealed an increase in the high-risk group, suggesting lasting epigenetic alterations. Together, we provide sound evidence of a disease-independent unfortunate relationship between well-defined pre-adult environmental hits and violent aggression, calling for more efficient prevention
Spinster Homolog 2 (Spns2) Deficiency Causes Early Onset Progressive Hearing Loss
Spinster homolog 2 (Spns2) acts as a Sphingosine-1-phosphate (S1P) transporter in zebrafish and mice, regulating heart development and lymphocyte trafficking respectively. S1P is a biologically active lysophospholipid with multiple roles in signalling. The mechanism of action of Spns2 is still elusive in mammals. Here, we report that Spns2-deficient mice rapidly lost auditory sensitivity and endocochlear potential (EP) from 2 to 3 weeks old. We found progressive degeneration of sensory hair cells in the organ of Corti, but the earliest defect was a decline in the EP, suggesting that dysfunction of the lateral wall was the primary lesion. In the lateral wall of adult mutants, we observed structural changes of marginal cell boundaries and of strial capillaries, and reduced expression of several key proteins involved in the generation of the EP (Kcnj10, Kcnq1, Gjb2 and Gjb6), but these changes were likely to be secondary. Permeability of the boundaries of the stria vascularis and of the strial capillaries appeared normal. We also found focal retinal degeneration and anomalies of retinal capillaries together with anterior eye defects in Spns2 mutant mice. Targeted inactivation of Spns2 in red blood cells, platelets, or lymphatic or vascular endothelial cells did not affect hearing, but targeted ablation of Spns2 in the cochlea using a Sox10-Cre allele produced a similar auditory phenotype to the original mutation, suggesting that local Spns2 expression is critical for hearing in mammals. These findings indicate that Spns2 is required for normal maintenance of the EP and hence for normal auditory function, and support a role for S1P signalling in hearing
Microcarrier cultivation of bovine aortic endothelial cells in spinner vessels and a membrane stirred bioreactor
Müthing J, Duvar S, Nerger S, Büntemeyer H, Lehmann J. Microcarrier cultivation of bovine aortic endothelial cells in spinner vessels and a membrane stirred bioreactor. CYTOTECHNOLOGY. 1995;18(3):193-206.Primary bovine aortic endothelial cells were cultivated in serum supplemented medium without any additional growth factors. The anchorage dependent cells were propagated on Dormacell(R) microcarriers with covalently bound dimeric DEAE-groups at the surface of the dextrane beads. Cultivations were performed in 200 ml spinner cultures containing 1 g l(-1) to 3 g l(-1) of microcarriers. Out of five types of Dormacell(R) microcarriers with different ion exchange capacities ranging from 0.30 up to 0.65 meg g(-1), corresponding to nitrogen contents from 1.2% to 2.9%, respectively, optimal attachment and growth of endothelial cells were obtained with beads of highest nitrogen content (2.9%). Cells were seeded with ca 5 viable cells per microcarrier being sufficient to achieve fully confluent microcarriers after 4 to 5 days. Glucose concentrations decreased from 21 mM to uppermost half of the original concentrations. 4 mM glutamine was rapidly consumed and virtually exhausted after the cells reached confluency. Lactate concentrations raised to a maximum of 7 mM in spinner cultures, but was found to be reutilized in the stationary phase after glutamine limitation occurred. Serine was found to be the second most prominent amino acid being almost exhausted at confluency whereas alanine was produced in noteworthy amounts. Considerable decrease was determined for threonine, lysine and arginine; low consumption rates were observed for leucine, phenylalanine and methionine. All other amino acids did not alter significantly throughout cultivation. These data support that bovine aortic endothelial cells are capable to utilize glucose and glutamine as well as lactic acid (after glutamine exhaustion) as energy and/or carbon source. Finally, batch cultures in a 2 liter membrane stirred bioreactor with bubble-free aeration were performed to produce large quantities of endothelial cells using microcarrier concentrations of 3 g 1(-1)
Modulation of the Glycosylation Repertoire of a Recombinant Human EPO Expressing Model Cell Line Under Different Culture Conditions
Cultivation of immortalized human hepatocytes HepZ on macroporous CultiSpher G microcarriers
Werner A, Duvar S, Müthing J, et al. Cultivation of immortalized human hepatocytes HepZ on macroporous CultiSpher G microcarriers. BIOTECHNOLOGY AND BIOENGINEERING. 2000;68(1):59-70.Cultivation of the new immortalized hepatocyte cell line HepZ was performed with a 1:1 mixture of DMEM and Ham's F12 media containing 5% FCS. The cells were grown in their 40th passage in 100 mL and 1 L volumes in spinner flasks and in a bioreactor, respectively. For the production of adherently growing HepZ cells macroporous CultiSpher G gelatin microcarriers were used in various concentrations from 1 to 3 g/L. The cells were seeded in a density of 2 x 10(5) cells/mL when using a microcarrier concentration of 1 g/L and 5 x 10(5) cells/mL at a microcarrier concentration of 3 g/L. After 7 days of cultivation a maximum cell concentration of 4.5 x 10(6) cells/mL was obtained in the spinner culture using a microcarrier concentration of 1 g/L. With bubble-free aeration and daily medium exchange from day 7, 7.1 x 10(6) cells/mL were achieved in the bioreactor using a microcarrier concentration of 3 g/L. The cells exhibited a maximum specific growth rate of 0.84 per day in the spinner system and 1.0 per day in the bioreactor, respectively. During the growth phase the lactate dehydrogenase (LDH) activity rose slightly up to values of 200 U/L. At the end of cultivation the macroporous carriers were completely filled with cells exhibiting a spherical morphology whereas the hepatocytes on the outer surface were flat-shaped. Concerning their metabolic activity the cells predominantly consumed glutamine and glucose. During the growth phase lactate was produced up to 19.3 mM in the spinner culture and up to 9.1 mM in the bioreactor. Maximal oxygen consumption was 1950 nmol/(10(6) cells day). HepZ cells resisted a 4-day long chilling period at 9.5 degrees C. The cytochrome P450 system was challenged with a pulse of 7 mu g/mL lidocaine at a cell density of 4.5 x 10(6) cells/mL. Five ng/mL monoethylglycinexylidide (MEGX) was generated within 1 day without phenobarbital induction compared to 26 ng/mL after a preceded three day induction period with 50 mu g/mL of phenobarbital indicating hepatic potency. Thus, the new immortalized HepZ cell line, exhibiting primary meta-belie functions and appropriate for a mass cell cultivation, suggests its application for a bioartificial liver support system. (C) 2000 John Wiley & Sons, Inc
Cultivation and Characterization of a New Immortalized Human Hepatocyte Cell Line, HepZ, for Use in an Artificial Liver Support System
On the structural diversity of Shiga toxin glycosphingolipid receptors in lymphoid and myeloid cells determined by nanoelectrospray ionization tandem mass spectrometry
Shiga toxin (Stx, synonymous to verotoxin, VT) binds with high and low affinity to the globo-series neutral glycosphingolipids (GSLs), globotriaosylceramide (Gb3Cer or Gal alpha 4Gal beta 4Glc beta 1Cer, also known as CD77) and globotetraosylceramide (Gb4Cer or GalNAc beta 3Gal alpha 4Gal beta 4Glc beta 1Cer), respectively, which represent the targets of Stxs on many different cell types. B-cell-derived Raji cells and THP-1 cells of monocytic origin are widely used for the investigation of Stx-mediated cellular response, because Stx is known to cause cell death in both cell lines. Despite their functional importance, the Stx receptors of Raji and THP-1 cells have so far not been investigated. This prompted us to explore the structures of their GSL receptors in detail by means of nanoelectrospray ionization quadrupole time-of-flight mass spectrometry (nanoESI-QTOF-MS) with collision-induced dissociation (CID) in conjunction with Stx1 as well as anti-Gb3Cer and anti-Gb4Cer antibodies. Using the combination of a thin-layer chromatography (TLC) overlay assay and MS1 and MS2 analysis we identified Gb3Cer (d18:1, C24:1/C24:0) as the prevalent Stx1-receptor accompanied by less abundant Gb3Cer (d18:1, C16:0) in the neutral GSL fraction of Raji cells. The same Gb3Cer species but with almost equal proportions of the C24:1/C24:0 and C16:0 variants were found in THP-1 cells. In addition, unusual hydroxylated Gb3Cer (d18:1, C24:1/C24:0) and Gb3Cer (d18:1, C26:1) could be identified in trace quantities in both cell lines. As the most obvious difference between Raji and THP-1 cells we observed the expression of Gb4Cer in THP-1 cells, whereas Raji cells failed to express this elongation product of Gb3Cer. Both short- and long-chain fatty acid carrying Gb4Cer (d18:1, C16:0) and Gb4Cer (d18:1, C24:1/C24:0), respectively, were the prevalent Gb4Cer variants. This first report on the differential expression of Gb3Cer and Gb4Cer and their structural diversity in lymphoid and myeloid cell lines supports the hypothesis that such heterogeneities might play a functional role in the molecular assembly of GSLs in membrane organization and cellular signaling of Stx-susceptible cells
