scholarly journals Induction of differentiation in cultured rat and human podocytes.

1997 ◽  
Vol 8 (5) ◽  
pp. 697-705 ◽  
Author(s):  
P Mundel ◽  
J Reiser ◽  
W Kriz
Keyword(s):  
Primary Cultures ◽  
Growth Arrest ◽  
Culture Conditions ◽  
Phenotypic Changes ◽  
Differentiated Cells ◽  
Intermediate Phenotypes ◽  
Induction Of Differentiation ◽  
Cell Culture Conditions

Mature podocytes are highly differentiated cells that are unable to divide in vivo. During glomerulogenesis, podocytes develop from simple cuboidal cells into their adult phenotype, which is characterized by a complex pattern of processes. Cultivation of podocytes under standard conditions leads to dedifferentiation, including the loss of processes and of pp44, a marker of differentiated podocytes. In this study, the cell culture conditions for rat and human podocytes were modified by avoiding repeated subcultivation. This led to profound phenotypic changes in podocytes in vitro. The conversion of cobblestones into arborized cells was directly observed, and a series of intermediate phenotypes was documented. The cells converted within 3 wk from typical cobblestone appearance into individual arborized cells more closely resembling in vivo podocytes. Arborized cells were frequently binucleated and reached a size of up to 500 microns. Both cobblestone and arborized cells originated from podocytes, as evidenced by the expression of a podocyte-specific O-acetylated ganglioside and of the WT-1 protein. In contrast to primary cultures and early passages of cobblestones, a cloned rat podocyte cell line did not express WT-1 and could not be induced to differentiate into arborized cells. This finding indicates a role for WT-1 in maintaining differentiation of adult podocytes. The differentiation of arborized cells led to growth arrest and was reflected by the formation of processes and the expression of pp44 and desmin, which were never detected in cobblestones. It was concluded that partial differentiation of cultured podocytes can be achieved simply by avoiding repeated subcultivation, resulting in an arborized phenotype more closely reflecting in vivo podocytes.

scholarly journals Induction of differentiation of promyelocytic NB4 cells by retinoic acid is associated with rapid increase in urokinase activity subsequently downregulated by production of inhibitors

Blood ◽  
1994 ◽  
Vol 83 (7) ◽  
pp. 1883-1891 ◽  
Author(s):  
H Tapiovaara ◽  
S Matikainen ◽  
M Hurme ◽  
A Vaheri
Keyword(s):  
Retinoic Acid ◽  
Growth Medium ◽  
Plasminogen Activator Inhibitor ◽  
Differentiated Cells ◽  
Plasminogen Activation System ◽  
Upa Receptor ◽  
Induction Of Differentiation ◽  
Activator Inhibitor

13-trans retinoic acid (13-trans RA) is an effective inducer of differentiation of acute promyelocytic (APL) cells both in vivo and in vitro. It is used in the induction of remission of patients with APL. We found, by using the promyelocytic NB4 cell line established from a patient with APL, that the induction of differentiation with RA was accompanied by modulation of the plasminogen activation system. The expression of urokinase (uPA) activity was rapidly increased in the growth medium and at the surface of cells treated with RA. The high uPA activity was counteracted both in the growth medium and at the cell surface by an increased plasminogen activator inhibitor (PAI) production and reduction of uPA synthesis. The expression of uPA receptor and PAI-2 were stimulated and persisted at 48 hours from RA addition. The simultaneous induction of CD11b suggests that differentiation results in increased production of both. APL patients often encounter episodes of disseminated intravascular coagulation that are associated with secondary fibrinolytic events. Our results suggest that downregulation of uPA activity results in the decrease of plasmin on the surface of the differentiated cells, which may reduce the occurrence of fibrinolytic episodes of patients with APL.

Two-dimensional gel pattern of proteins synthesized de novo in lymphoid organs of the mouse.

1984 ◽  
Vol 30 (12) ◽  
pp. 2043-2047 ◽  
Author(s):  
G Pluschke ◽  
I Lefkovits
Keyword(s):  
De Novo ◽  
Culture Conditions ◽  
Detection Methods ◽  
Lymphoid Tissues ◽  
Two Dimensional ◽  
In Vivo Labeling ◽  
Labeling Method ◽  
Cell Culture Conditions

Abstract Mice were injected intravenously with 1 mCi of [35S]methionine, and serum and tissue were sampled 4 h later. Serum and lymphoid and non-lymphoid tissues had all incorporated enough labeled methionine to allow radiofluorographic detection on two-dimensional gels of proteins synthesized de novo and, by comparing radiofluorographs, we could distinguish spots peculiar to a given tissue from others more ubiquitous. We selected a protein of 17-kDa apparent molecular mass and pl about 4 to demonstrate tissue specificity. All patterns obtained for thymus samples yielded this spot; in all other immunologically relevant sites it was missing or weak. It also was not detected on gels previously obtained from lymphocyte subpopulations biosynthetically labeled in vitro. The labeling method described here will be especially helpful for characterizing cell populations that cannot be radiolabeled under cell-culture conditions. In contrast to detection methods that detect all proteins of a sample, in vivo labeling allows specific recognition of de novo synthesized proteins. Therefore it will facilitate comparison and detection of proteins produced by an animal in response to a given treatment.

scholarly journals Induction of differentiation of promyelocytic NB4 cells by retinoic acid is associated with rapid increase in urokinase activity subsequently downregulated by production of inhibitors

Blood ◽  
1994 ◽  
Vol 83 (7) ◽  
pp. 1883-1891 ◽  
Author(s):  
H Tapiovaara ◽  
S Matikainen ◽  
M Hurme ◽  
A Vaheri
Keyword(s):  
Retinoic Acid ◽  
Growth Medium ◽  
Plasminogen Activator Inhibitor ◽  
Differentiated Cells ◽  
Plasminogen Activation System ◽  
Upa Receptor ◽  
Induction Of Differentiation ◽  
Activator Inhibitor

Abstract 13-trans retinoic acid (13-trans RA) is an effective inducer of differentiation of acute promyelocytic (APL) cells both in vivo and in vitro. It is used in the induction of remission of patients with APL. We found, by using the promyelocytic NB4 cell line established from a patient with APL, that the induction of differentiation with RA was accompanied by modulation of the plasminogen activation system. The expression of urokinase (uPA) activity was rapidly increased in the growth medium and at the surface of cells treated with RA. The high uPA activity was counteracted both in the growth medium and at the cell surface by an increased plasminogen activator inhibitor (PAI) production and reduction of uPA synthesis. The expression of uPA receptor and PAI-2 were stimulated and persisted at 48 hours from RA addition. The simultaneous induction of CD11b suggests that differentiation results in increased production of both. APL patients often encounter episodes of disseminated intravascular coagulation that are associated with secondary fibrinolytic events. Our results suggest that downregulation of uPA activity results in the decrease of plasmin on the surface of the differentiated cells, which may reduce the occurrence of fibrinolytic episodes of patients with APL.

In Vitro Culture of Human Thyroid Cells: Preliminary Findings on the Role of the Pathological Condition of the Donors

1997 ◽  
Vol 25 (2) ◽  
pp. 153-160
Author(s):  
Francesca Mattioli ◽  
Marianna Angiola ◽  
Laura Fazzuoli ◽  
Francesco Razzetta ◽  
Antonietta Martelli
Keyword(s):  
Pathological Condition ◽  
Primary Cultures ◽  
S Phase ◽  
Human Thyroid ◽  
Thyroid Cells ◽  
Toxicological Studies ◽  
Predictive Indicator

Although primary cultures of human thyroid cells are used for endocrinological and toxicological studies, until now no attention has been paid toward verifying whether the hormonal conditions to which the gland was exposed in vivo prior to surgery could influence in vitro responses. Our findings suggest that the hormonal situation in vivo cannot be used as a predictive indicator of triiodothyronine and thyroxine release and/or S-phase frequency in vitro, either with or without the addition of bovine thyrotropin.

scholarly journals Transcriptome comparisons of in vitro intestinal epithelia grown under static and microfluidic gut-on-chip conditions with in vivo human epithelia

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kornphimol Kulthong ◽  
Guido J. E. J. Hooiveld ◽  
Loes Duivenvoorde ◽  
Ignacio Miro Estruch ◽  
Victor Marin ◽  
...  
Keyword(s):  
Gene Expression ◽  
Culture Conditions ◽  
Gene Set Enrichment Analysis ◽  
Shear Stresses ◽  
Static Culture ◽  
Dynamic Culture ◽  
Intestinal Segments ◽  
On Chip

AbstractGut-on-chip devices enable exposure of cells to a continuous flow of culture medium, inducing shear stresses and could thus better recapitulate the in vivo human intestinal environment in an in vitro epithelial model compared to static culture methods. We aimed to study if dynamic culture conditions affect the gene expression of Caco-2 cells cultured statically or dynamically in a gut-on-chip device and how these gene expression patterns compared to that of intestinal segments in vivo. For this we applied whole genome transcriptomics. Dynamic culture conditions led to a total of 5927 differentially expressed genes (3280 upregulated and 2647 downregulated genes) compared to static culture conditions. Gene set enrichment analysis revealed upregulated pathways associated with the immune system, signal transduction and cell growth and death, and downregulated pathways associated with drug metabolism, compound digestion and absorption under dynamic culture conditions. Comparison of the in vitro gene expression data with transcriptome profiles of human in vivo duodenum, jejunum, ileum and colon tissue samples showed similarities in gene expression profiles with intestinal segments. It is concluded that both the static and the dynamic gut-on-chip model are suitable to study human intestinal epithelial responses as an alternative for animal models.

scholarly journals TMOD-15. EFFICACY OF THE MDM2 INHIBITOR KRT-232 IN GLIOBLASTOMA PATIENT-DERIVED XENOGRAFT MODELS

2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii231-ii231
Author(s):  
Rachael Vaubel ◽  
Ann Mladek ◽  
Yu Zhao ◽  
Shiv K Gupta ◽  
Minjee Kim ◽  
...  
Keyword(s):  
Target Genes ◽  
Xenograft Model ◽  
Culture Conditions ◽  
Patient Derived Xenograft ◽  
Fold Induction ◽  
Extended Survival ◽  
Mdm2 Amplification ◽  
Mdm2 Inhibitor

Abstract Non-genotoxic reactivation of p53 by MDM2 inhibitors represents a promising therapeutic strategy for tumors with wild-type TP53, particularly tumors harboring MDM2 amplification. MDM2 controls p53 levels by targeting it for degradation, while disruption of the MDM2-p53 interaction causes rapid accumulation of p53 and activation of the p53 pathway. We examined the efficacy of the small molecule MDM2 inhibitor KRT-232, alone and in combination with radiation therapy (RT), in MDM2-amplified and/or p53 wildtype patient-derived xenograft (PDX) models of glioblastoma in vitro and in vivo. In vitro, glioblastoma PDX explant cultures showed sensitivity to KRT-232, both tumors with MDM2 amplification (GBM108 and G148) and non-amplified but TP53-wildtype lines (GBM10, GBM14, and GBM39), with IC50s ranging from 300-800 nM in FBS culture conditions. A TP53 p.F270C mutant PDX (GBM43) was inherently resistant, with IC50 >3000 nM. In the MDM2-amplified GBM108 line, KRT-232 led to a robust (5-6 fold) induction of p53-target genes p21, PUMA, and NOXA, with initiation of both apoptosis and senescence. Expression of p21 and PUMA was greater with KRT-232 in combination with RT (25-35 fold induction), while stable knock-down of p53 in GBM108 led to complete resistance to KRT-232. In contrast, GBM10 showed lower induction of p21 and PUMA (2-3 fold) and was more resistant to KRT-232. In an orthotopic GBM108 xenograft model, treatment with KRT-232 +/- RT for one week extended survival from 22 days (placebo) to 46 days (KRT-232 alone); combination KRT-232 + RT further extended survival (77 days) over RT alone (31 days). KRT-232 is an effective treatment in a subset of glioblastoma pre-clinical models alone and in combination with RT. Further studies are underway to understand the mechanisms conferring innate sensitivity or resistance to KRT-232.

scholarly journals Self-organization and culture of Mesenchymal Stem Cell spheroids in acoustic levitation

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Nathan Jeger-Madiot ◽  
Lousineh Arakelian ◽  
Niclas Setterblad ◽  
Patrick Bruneval ◽  
Mauricio Hoyos ◽  
...  
Keyword(s):  
Cell Culture ◽  
3D Cell Culture ◽  
Culture Conditions ◽  
Acoustic Levitation ◽  
Cell Sheets ◽  
Cell Therapies ◽  
Cellular Models ◽  
Cell Spheroids

AbstractIn recent years, 3D cell culture models such as spheroid or organoid technologies have known important developments. Many studies have shown that 3D cultures exhibit better biomimetic properties compared to 2D cultures. These properties are important for in-vitro modeling systems, as well as for in-vivo cell therapies and tissue engineering approaches. A reliable use of 3D cellular models still requires standardized protocols with well-controlled and reproducible parameters. To address this challenge, a robust and scaffold-free approach is proposed, which relies on multi-trap acoustic levitation. This technology is successfully applied to Mesenchymal Stem Cells (MSCs) maintained in acoustic levitation over a 24-h period. During the culture, MSCs spontaneously self-organized from cell sheets to cell spheroids with a characteristic time of about 10 h. Each acoustofluidic chip could contain up to 30 spheroids in acoustic levitation and four chips could be ran in parallel, leading to the production of 120 spheroids per experiment. Various biological characterizations showed that the cells inside the spheroids were viable, maintained the expression of their cell surface markers and had a higher differentiation capacity compared to standard 2D culture conditions. These results open the path to long-time cell culture in acoustic levitation of cell sheets or spheroids for any type of cells.

scholarly journals Expression of laminin γ 1 cultured hepatocytes involves repeated CTC and GC elements in the LAMC1 promoter

1996 ◽  
Vol 313 (3) ◽  
pp. 745-752 ◽  
Author(s):  
Françoise LEVAVASSEUR ◽  
Jocelyne LIÉTARD ◽  
Kohei OGAWA ◽  
Nathalie THÉRET ◽  
Peter D. BURBELO ◽  
...  
Keyword(s):  
Transcriptional Activation ◽  
Hepatoma Cell ◽  
Primary Cultures ◽  
Regulatory Elements ◽  
Hepatoma Cells ◽  
Basement Membranes ◽  
Major Protein ◽  
Cultured Hepatocytes

Laminin γ1 chain is present in all basement membranes and is expressed at high levels in various diseases, such as hepatic fibrosis. We have identified cis- and trans-acting elements involved in the regulation of this gene in normal rat liver, as well as in hepatocyte primary cultures and hepatoma cell lines. Northern-blot analyses showed that laminin γ1 mRNA was barely detectable in freshly isolated hepatocytes and expressed at high levels in hepatocyte primary cultures, as early as 4 h after liver dissociation. Actinomycin D and cycloheximide treatment in vivo and in vitro indicated that laminin γ1 overexpression in cultured hepatocytes was under the control of transcriptional mechanisms. Transfection of deletion mutants of the 5´ flanking region of murine LAMC1 gene in hepatoma cells that constitutively express laminin γ1 indicated that regulatory elements were located between -594 bp and -94 bp. This segment included GC- and CTC-containing motifs. Gel-shift analyses showed that two complexes were resolved with different affinity for the CTC sequence depending on the location of the GC box. The pattern of complex formation with nuclear factors from freshly isolated and cultured hepatocytes was different from that obtained with total liver and similar to that with hepatoma cells. Southwestern analysis indicated that several polypeptides bound the CTC-rich sequence. Affinity chromatography demonstrated that a Mr 60000 polypeptide was a major protein binding to the CTC motif. This polypeptide is probably involved in the transcriptional activation of various proto-oncogenes and extracellular matrix genes that are expressed at high levels in both hepatoma cells and early hepatocyte cultures.

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